Introduction: Non-Small Cell Lung Cancer is the most prevalent type of cancer in lung cancer. Chemotherapy, radiation therapy, and other conventional cancer treatments have a low success rate. Thus, creating new medications is essential to halt the spread of lung cancer.Methods: In this study bioactive nature of lochnericine against Non-Small Cell Lung Cancer (NSCLC) was analyzed using various computational approaches such as quantum chemical calculations, molecular docking, and molecular dynamic simulation. Furthermore, the MTT assay shows the anti-proliferation activity of lochnericine.Results and Discussion: Using Frontier Molecular Orbital (FMO), the calculated band gap energy value associated with bioactive compounds and the molecule’s potential bioactivity is confirmed. The H38 hydrogen atom and O1 oxygen atom in the molecule are effectively electrophilic, and potential nucleophilic attack sites were confirmed through analysis of the Molecular electrostatic potential surface. Furthermore, the electrons within the molecule were delocalized, which confers bioactivity on the title molecule and was authorized through Mulliken atomic charge distribution analysis. A molecular docking study revealed that lochnericine inhibits non-small cell lung cancer-associated targeted protein. The lead molecule and targeted protein complex were stable during molecular dynamics simulation studies till the simulation period. Further, lochnericine demonstrated remarkable anti-proliferative and apoptotic features against A549 lung cancer cells. The current investigation powerfully suggests that lochnericine is a potential candidate for lung cancer. Traditi (NSCLC) .Catharanthusroseus) and formed by the stereoselective C6, C7-epoxidation of tabersonine. The stereoselective C6 produces Lochnericine and C7-epoxidation of tabersonine and can be subsequently metabolized to produce more complex MIAs. Although the enzymes in charge of its downstream modifications have been identified, those in charge of lochnericine production have not.In cancer treatment, natural products may be used in addition to traditional anticancer medications. Recently, researchers worldwide have focused on developing novel drugs with medicinal potential derived from natural sources such as plants. Plants and their phytoconstituents have been used for medical purposes since antiquity . Naturalvia ligand-provoked dimerization  influences cell proliferation, cell division, and tumour development. It is a representative transmembrane receptor which triggers signalling pathways rization . In humarization . There irization . This stThe most stable molecular structure of lochnericine was optimized using the Gaussian 09 software, and the DFT/B3LYP method with LANL2DZ was used to optimize the structure. The Los Alamos National Laboratory 2 double zeta (LANL2DZ) for transition metals and all-electron basis sets for all other non-transition metal atoms are used more frequently in computations on systems including transition metals. . The molIn the present study, target receptor molecules, including EGFR [PDB ID: 2ITY], KRAS [PDB ID: 7LGI], Ntrk [PDB ID: 7VKO], and ALK [PDB ID: 2XP2], were obtained from the RCSB Protein Data Bank . TRIM11 Molecular docking was performed using Vina version 2.0 in PyRX . In the p values represent the lipophilicity of the compounds. The logarithmic S value represents the solubility of water. Human gastrointestinal absorption (HIA) and blood-brain barrier (BBB) permeation were predicted pharmacokinetic properties in swiss adme.ADME prediction was performed in the SWISS ADME tool . This to+ and Cl−) were also included in the simulation systems (In simulation studies using molecular dynamics (MD), the atomic and molecular motions within the protein structure were examined. Atoms and molecules can interact for 100 ns in the GROMACS  . Macromo systems . Adding  systems .Sigma, St Louis, MO, United States, supplied the dimethyl sulfoxide (DMSO) and Lochnericine. All other chemicals and solvents were purchased from SISCO Research Laboratories (SRL). Lochnericine was synthesized in a serum-free RPMI medium after being dissolved in dimethyl sulfoxide (DMSO) at a final concentration of less than 0.1 percent (v/v). It did not affect cell viability) and filtered through a 0.045 mm syringe filter before being stored at 4°C.5 cells were cultured with 0.5 mL medium/well, 37°C temperature was maintained with CO2 5%, and relative humidity was about 95%. For 48 h, cells were treated with various concentrations of lochnericine. The cells were incubated at 37°C for 4 h after adding 200 µl of MTT solution (5 mg/mL), and cells were harvested. Through the gentle aspiration method, the medium and unread MTT were detached. At room temperature, the plates were shaken well for 5 min by adding 500 µl of DMSO. The crystallized dye was extracted by adding 1 mL of DMSO to the well. At 570 nm absorbance, the quantity of blue dye formed was estimated. The proliferation of the cells was examined by microscopic visualization at 48X magnification. The control and drug-treated cells were treated with 10% methanol for 5 min. Then cells were viewed under an inverted microscopeto confirm the anti-proliferative efficacy of the drug.The MTT assay was employed to assess the anti-proliferative efficacy of lochnericine against A549 lung cancer cells. Through mitochondrial enzymes, the translation of MTT -2,5-diphenyltetrazolium bromide) to the formation of MTT is the critical mechanism involved in this cytotoxicity assay. NCCS Pune supplied the lung cancer cell line A549 for this investigation. In 24 well tissue culture plates, 2x 10The mean and standard deviation data were displayed (SD). The noteworthyvariances were calculated using a one-way analysis of variance (ANOVA). A commercial software application (SPSS version 20) was employed for statistical analysis. SPSS offers data analysis for descriptive and bivariate statistics, numerical result forecasts, and predictions for classifying groups.The Lochnericine molecule’s molecular structure was optimized using the DFT/B3LYP method with the cc-pVTZ basis set . Figure 49 atoms and 141 normal vibration modes are present in the lochnericine, and all belong to the same symmetry species. The calculated values oflochnericinevibrational frequencies, IR intensity, and activity of Raman scattering have been represented in The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are the two molecular orbitals that are used to analyse how a molecule interacts with other species (LUMO). The HOMO energy represents the capacity to provide electrons, whereas the LUMO energy represents the capacity to carry electrons . ElectriRed, yellow, light blue, and blue on the MEP surface  represenMulliken’s atomic charge distribution influences the molecule’s dipole moment, electrostatic potential, electronegativity equalization, electronic structure, vibrational modes, and polarizability . BecauseIn drug designing, molecular docking is essential to determine the binding mode and efficacy of the active lead molecules. Molecular docking approaches were performed for all targeted receptor molecules. Receptor molecules docking score and interacting residues were tabulated in In the drug-designing process, ADME prediction is essential for determining the lead molecule’s efficacy. These obey all the five rules of Lipinski. Several pharmacokinetic properties, pharmacokinetics, drug-likeness, and water solubility properties were tabulated in Gromacs package’s molecular dynamics simulations were used to examine the stability of targeted protein-ligand complexes. Based on the docking score, interaction residues, and binding affinity between the targeted proteins and the Lochnericine. For 50 ns, molecular dynamics simulations were performed. Typically, MD simulation is used to predict the behaviour of macromolecules, and it relies on classical mechanics and Newton’s equation of motion to determine the speed and position of each atom in the system under consideration. As a result, MD performs a more concise structural assessment. The difference between the initial and final structural conformational positions was determined using the RMSD (Root Mean Square Deviation). The results of MDs of protein-ligand complexes are shown in Several chemicals and natural compounds’ cytotoxic efficacy against malignant cells have been considered primary studies for the antitumor potential of the compounds. The conversion of MTT -2, 5-diphenyltetrazolium bromide) to MTT-formation using mitochondrial enzymes in the MTT assay is a notable assay for the valuation of the proliferation of cancer cells . TreatmeThe optimization geometry for the lochnericine bioactive molecule was carried out using the DFT/B3LYP functional technique and the cc-PVTZ basis set. Simulated Lochnericine vibrational spectra, including infrared and Raman spectra, showed that the computed vibrational wavenumbers significantly correspond with those from earlier works of literature. The determined band gap energy value of 4.18 eV abutment lochnericine bioactivity. H38 hydrogen and O1 oxygen atom in the molecule are possible electrophilic and nucleophilic attack sites, according to a molecular electrostatic potential surface analysis. An examination of the atomic charge distribution of Mulliken verified the electron delocalization that led to the molecule’s bioactivity. non-small cell lung cancer potential targeted receptor molecules were selected and analyzed using a computational approach. During molecular docking studies, all the targeted receptor has a strong binding affinity for drugs containing lochnericine. Further targeted receptor and lochnericinedocked complexes showed good stability and lesser fluctuation during the simulation time. The protein-ligand complexes are more stable when their RMSD value is smaller. Every targeted receptor molecule has a lead compound deviation that seems to be smaller than 0.4 nm. Within a 0.50 nm range, the targeted protein-ligand complex fluctuates. While accounting for the studied complexes, the lowest values for the deviation below 0.40 nm and the lesser deviation below 1 nm were obtained. The targeted protein-ligand complexes exhibit good stability and flexibility, according to RMSD and RMSF analysis. Throughout the simulation, better hydrogen bond interaction can be seen in the resulting complexes with lochnericine.


Dopamine detection in dopamine-depleted brain homogenates spiked with dopamine was also possible with a LOD of 1 aM, overcoming sensitivity losses typically observed in ion-sensitive sensors in complex biological samples. Furthermore, we show that our gMTAs platform can detect minimal changes in dopamine concentrations in small working volume samples (2 µL) of cerebral spinal fluid samples obtained from a mouse model of Parkinson’s Disease. The platform presented in this work can lead the way to graphene-based neurotransmitter sensors suitable for real-world academic and pre-clinical pharmaceutical research as well as clinical diagnosis.Detecting physiological levels of neurotransmitters in biological samples can advance our understanding of brain disorders and lead to improved diagnostics and therapeutics. However, neurotransmitter sensors for real-world applications must reliably detect low concentrations of target analytes from small volume working samples. Herein, a platform for robust and ultrasensitive detection of dopamine, an essential neurotransmitter that underlies several brain disorders, based on graphene multitransistor arrays (gMTAs) functionalized with a selective DNA aptamer is presented. High-yield scalable methodologies optimized at the wafer level were employed to integrate multiple graphene transistors on small-size chips (4.5 × 4.5 mm). The multiple sensor array configuration permits independent and simultaneous replicate measurements of the same sample that produce robust average data, reducing sources of measurement variability. This procedure allowed sensitive and reproducible dopamine detection in ultra-low concentrations from small volume samples across physiological buffers and high ionic strength complex biological samples. The obtained limit-of-detection was 1 aM (10The online version contains supplementary material available at 10.1186/s12951-022-01695-0. Neurotransmitters are molecules indispensable for the communication between neurons and play a critical role in brain function. The accurate detection of neurotransmitter concentrations in the brain and biological samples is of great importance for neurobiology research and developing novel diagnostic and therapeutic approaches for brain disorders affecting neurotransmitter levels and dynamics. A significant neurotransmitter is dopamine , which has essential roles in the human brain and body, regulating several physiological processes involved in motor function, memory, motivation, arousal, and reward . AbnormaGraphene-based biosensors have been attracting growing attention due to their extremely high sensitivity based on graphene’s unique electronic properties, high chemical and mechanical stability, and biocompatibility –17. GrapConsequently, a wide range of selective biosensing applications with gFETs, including protein and DNA detection in optimized buffers and samples prepared from body fluids such as blood, sweat, or saliva, has been reported in the last decade , 26, 27,Additionally, many of the recently proposed graphene biosensors do not address issues relating to fabrication methods' replicability and scalability and the desired measurements' stability and reproducibility. Thus, despite significant efforts, the deployment of graphene-based point-of-care devices and reliable academic and pharmaceutical research tools has been limited. Wafer-scale graphene synthesis and fabrication of graphene biosensors with replicable methodologies can improve device uniformity and facilitate integrated designs with multiplexed parallel assays for high-throughput measurements , 34–37, This work proposes a biosensing platform that permits ultrasensitive and selective dopamine detection, yielding stable and reliable results by high-throughput single-sample measurement replication. Micron-sized electrolyte-gated field-effect graphene transistors (EG–gFETs) were fabricated with reproducible methodologies optimized at the wafer level and integrated into miniaturized multitransistor array (gMTA) chips. These arrays were converted into aptasensors by functionalizing the EG–gFETs with a short-strand dopamine-specific DNA aptamer. The array format introduced here allows single-sample measurement replication within each gMTA, producing robust average data and reducing sources of measurement variability. By taking advantage of this novel feature, the high mobility of graphene's charge carriers, and the effective screening of the aptamer's charge redistribution upon dopamine binding, a record LOD for dopamine and wide sensing ranges are reported. The obtained LOD of 1aM is three orders of magnitude lower than the lowest dopamine LOD previously reported. Furthermore, we show that these gMTAs can detect minimal changes in dopamine concentration in small working volume (2 µL) biological cerebrospinal fluid (CSF) and brain homogenate samples from an animal model of PD. This feature is highly pertinent for developing novel point-of-care devices and research tools that require stable high-throughput detection of physiologically and clinically relevant dopamine concentrations.2 wafer containing 784 graphene multi-transistor arrays (gMTAs) with 15,680 electrolyte-gated graphene field-effect transistors (EG–gFETs), with a yield of approximately 80%, was fabricated for this work  changes for a particular gate voltage (VGS), was assessed after each functionalization step , with a left branch (VGS < VDIRAC) representing the excursion of the electrochemical potential (µ) in the valence band (p-branch) and a right branch (VGS > VDIRAC) representing the excursion of µ in the conduction band (n-branch), is very distinct from semiconductor-based FETs and demonstrates the bipolar character of graphene transistors [DS is at its minimum at the Dirac point and tracking the VDIRAC value can be used as a proxy for transfer curve shifts  by comparing experimental peak parameters for O 1 s, C 1 s, N 1 s, P 2p from graphene samples incubated with either PBASE or PBASE followed by the aptamer  to nM (10–9). The selectivity of the gMTA aptasensor against dopamine synthesis molecules and biological interferents was also assessed.For initial validation of the gMTAs dopamine detection in ultra-low concentrations, as well as to establish calibration curves, in vitro experiments were performed in undiluted phosphate-buffered saline (1 × PBS) and artificial cerebrospinal fluid (1 × aCSF) Fig. A. DopamiDIRAC) to dopamine was obtained by serially incubating solutions of increasing dopamine concentrations in undiluted phosphate-buffered saline (1 × PBS)   dopamine concentration. From 1 aM (10–18) dopamine concentration, gMTAs presented a linear detection range up to 1 fM (10–15), with linear increases of VDIRAC as a function of dopamine concentration with a 9.5 mV/decade sensitivity  is found at more positive gate voltages, required to bring µ back to the Dirac point.A calibration curve for the gMTAs response (ΔVBS) Fig. B. VDIRACd saline  × PBS  obtained with our gMTAs is 3 orders of magnitude lower than the lowest LOD ever reported for any dopamine sensor, currently at 0.5 fM (10–15) [The dopamine LOD of 1 aM (10 (10–15) , 13, and (10–15)  or graph (10–15) ; (ii) th (10–15) ; (iii) t (10–15) , 51; (iv (10–15) , 47, 52.–17)  [–11) with a 22 mV/decade sensitivity  were acquired Fig. C. aCSF d17) Fig. C, which ig. –14) . The dynDIRAC, which means that the graphene electrochemical potential moved up in energy relative to the density of states (n-doping). The sign of VDIRAC shifts depends on several mechanisms involving interactions between the probe and the target and between the electrolytic solution and the probe and target [2+ and Mg2+, which are present in aCSF [Contrary to the calibration curve in 1 × PBS, adding dopamine to the gMTAs in 1 × aCSF led to negative shifts of Vd target . Thus, o in aCSF , 50. TheAlthough aptamers typically present high stability at variable pH, changes in the ionic composition of the electrolytic solution can alter aptamers’ conformation and FETs performance , 69, as Selectivity assessment. Evaluating the selectivity of novel biosensors is paramount for successful real-world applications with biological samples where the target molecule is mixed with various other molecules. Brain dopamine or dopamine in brain-derived samples, such as biological CSF, occurs at minute concentrations and is mixed with other neurotransmitters, amino acids, and proteins. Thus, to test the selectivity of the gMTAs, their response to dopamine was compared with the response to molecules in the dopamine synthesis pathway, including L-Dopa and L-Tyrosine, chemically similar to dopamine, and ascorbic acid, a ubiquitous biological interferent typically occurring in higher concentrations than neurotransmitters. The latter is involved in norepinephrine synthesis from dopamine and is likely to co-occur with dopamine in the brain [he brain . The reshe brain .Biosensors developed and optimized based on in vitro assays tend to underperform in biological samples, losing sensitivity and selectivity. This underperformance, also observed in previous ion-sensitive dopamine biosensors , 13, is A reserpine-induced mouse model of Parkinson’s Disease (PD) was used for these experiments. This animal model has been instrumental in elucidating the role of abnormal dopamine levels in PD symptomatology and used to develop critical therapeutics for PD that modulate these levels, such as L-DOPA administration , 73. Rescisterna magna puncture [DIRAC shifts of samples from parkinsonian animals  with those of control animals (mean ΔVDIRAC: 51 ± 11 mV)  and parkinsonian (reserpine-treated) mice was assessed Fig. A. Dopamipuncture , a methopuncture . Pairs omV) Fig. A. Of notAdditionally, the gMTAs displayed significantly higher sensitivity than previously developed biosensors for dopamine detection in CSF while requiring significantly lower sample working volumes –83. The –18) to nM (10–8) , and a wide dynamic range from 1 aM (10–18) to 100 µM (10–8) was obtained  animals were collected and spiked with increasing dopamine concentrations. A series of samples were prepared from stock solution, from aM (10–8) Fig. B. The gM–8) Fig. B. The obned Fig. B.DIRAC shifts away from baseline values were observed, denoting the absence of dopamine detection  for dopamine detection proposed here, combining an array of graphene field-effect transistors with a selective DNA aptamer, achieved ultrasensitive and stable dopamine detection in various media from physiological ionic-strength buffers to complex biological samples. Notably, the gMTAs detected dopamine changes in small working volume CSF samples from a Parkinson’s Disease (PD) animal model, which can pave the way for novel point-of-care diagnostic devices to detect abnormal levels of dopamine in PD, and in other dopamine-dependent brain disorders such as Alzheimer’s Disease, and substance addiction disorders. Using numerous EG–gFET aptasensors in an array configuration further allows future multiplexed measurements of different biomarkers in one single gMTA through the localized biofunctionalization of individual EG–gFETs. Lastly, the fabrication at the wafer level lends itself to developing different array configurations, including with higher EG–gFETs count, which may be relevant for a high-throughput assessment of localized dopamine release. Increased sensors’ spatial density and tracking real-time independent localized measurements with single-cell resolution from each EG–gFET or subsets of transistors in the arrays are future features that can be realized without significant changes to the overall fabrication process. This possibility is especially relevant for fundamental neuroscience or pharmaceutical studies of brain disorders requiring measurements from ex vivo brain slices from animal models or human patients’ IPSC-derived cell cultures and in vivo monitoring in intact brains. As the proposed sensor is further tested in other biologically relevant samples and in in vivo scenarios, it can ultimately help elucidate our understanding of the brain and promote the development of improved diagnostics and therapeutics for brain disorders.3,4-dihydroxyphenethylamine hydrochloride (Dopamine hydrochloride), 3,4-Dihydroxyl-L-phenylalaline (L-DOPA) (98% TLC), L-Tyrosine (98% HPLC), L-Ascorbic acid (99%), Phosphate-buffered saline (PBS) tablets, N,N-Dimethylformamide (DMF) (99.9% HPLC), 1-Pyrenebutynic acid N-hydroxy-succinimide ester (PBASE) (95%), 1-Dodecanethiol (DDT) (98%), Ethanolamine (ETA) (98%), Sodium Chloride (NaCl), Potassium Chloride (KCl), Monosodium Phosphate (NaH2PO4), Sodium Bicarbonate (NaHCO3), Glucose, Calcium Chloride Dihydrate (CaCl2.2H2O), Acetic Acid Glacial, Hydrochloric acid (HCl) (35%), Sodium Hydroxide (NaOH) tablets, and Poly(methyl(meth)acrylate) (PMMA) (15 k M.W.) were purchased from Sigma-Aldrich. Acetone (99.5%), Ethanol (99.8%), and 2-Propanol (99.8% GC) were purchased from Honeywell. Magnesium Sulfate Heptahydrate (MgSO4.7H2O) was purchased from Merck. Photoresist AZ1505 (AZ) was purchased from MicroChemicals GmbH. RTV silicone elastomer  and superglue (Loctite) were acquired from Farnel. DNA aptamer (5′-CGACGCCAGTTTGAAGGTTCGTTCGCAGGTGTGGAGTGACGTCG-3′) with a 5′ C6-amino link modification was synthesized by Stab Vida. Reserpine was acquired from Biogen. MilliQ water used in all experiments had a resistivity higher than 18 MΩ cm at 25 °C.2 Cu substrates were initially treated with a mixture of FeCl3, HCl, and deionized water (DI) for 1 min in ultrasound and then placed in the furnace. The system was evacuated to approximately 2 mTorr and then filled with 250-sccm Argon  and 60-sccm Hydrogen  gas mixture. Once the growth temperature and pressure were reached, methane (0.5 sccm), the carbon precursor, was introduced into the chamber. The growth was carried out at 1040 °C at 6 Torr for 25 min. After growth, SLG was protected by poly(methyl(meth)acrylate) (PMMA), and plasma ashing was performed to remove the graphene from the backside of the substrate. Raman spectroscopy was used to assess the quality of grown graphene  were fabricated by building on our previously published processes for wafer-scale fabrication of electrolyte-gated graphene field-effect transistors (EG–gFETs) with an integrated receded gate electrode and improved multilayer dielectric passivation for biosensing applications , 44. Bri2O3) (20 nm) capping. The source, drain, and gate electrodes were patterned by optical lithography and etched by ion milling. A sacrificial layer  was sputtered and patterned via lift-off, exposing the channel region and the source and drain electrodes for graphene transfer. Previously grown SLG, as described above, was transferred onto the wafer, patterned with optical lithography, and dry-etched with oxygen plasma. The sacrificial layer was then removed by wet etch. A protective layer  was sputtered and patterned by sonication-free lift-off to work as a stopping layer for reactive ion etching (RIE) at the graphene channel and gate electrode. A 250 nm multi-stack passivation layer of SiO2 and Si3N4 was grown by plasma-enhanced CVD and patterned by RIE. Finally, the stopping layer was dry-etched to expose the graphene channel and gate electrode. The EG–gFETs were characterized electrically at the wafer level with an automated probe station by measuring the resistance between each transistor’s source and drain electrodes at a fixed voltage of 1 mV or a fixed current of 1 μA. gMTAs with transistors with resistance above 2.5 MΩ were discarded from further experiments. The wafer was finally coated with photoresist for protection and diced into individual 4.5 × 4.5 mm gMTA chips. The chips were then glued onto custom-designed printed circuit boards (PCB) for electronic interfacing, and their interconnection pads were wire-bonded with gold wires to the PCB pads. Finally, the wires and connection pads were protected with a silicone elastomer.For wafer-level fabrication of EG–gFETs, a 200 mm silicon (Si) wafer with 100 nm of thermal oxide was used as substrate. The wafer was sputter-coated with Chromium (Cr) (3 nm) as an adhesion layer, Gold (Au) (35 nm) as the conductive layer, and an alumina , were added to the gMTAs and incubated for 2 h in a humid chamber. A 44nt-long DNA aptamer (5′-CGACGCCAGTTTGAAGGTTCGTTCGCAGGTGTGGAGTGACGTCG-3′), previously selected for high affinity to dopamine [2 flow. The transconductance of each EG–gFET aptasensor in the arrays was measured at each step of the functionalization process by applying a source-drain voltage (VDS) of 1 mV and measuring source-drain current (IDS) in gate-source voltage (VGS) sweeps between 0 and 1 V.EG–gFETs in each gMTA chip were first incubated for 4 h in 2 mM 1-Dodecanethiol  for gate passivation, then cleaned with DI water and dried under Ndopamine , with a 2 substrates. Previously grown SLG was transferred to the substrate, after which samples were incubated with the PBASE crosslinker (for 2 h). Half of the samples were then incubated with the dopamine-specific aptamer (for 16 h). The PBASE and aptamer incubation times were the same as for the transistor’s graphene functionalization. Survey scans were performed from 0 to 1350 eV with a pass energy of 50 eV. High-resolution spectra for carbon, nitrogen, oxygen, and phosphorous were completed for graphene + PBASE and graphene + PBASE + aptamer samples. Advantage software (Thermofisher) was used for peak fitting and calculating atomic percentages.X-ray photoelectron spectroscopy (XPS) analysis was performed with an ESCALAB 250Xi system (Thermo Scientific). A thermal p-doped silicon oxide wafer was coated with a photoresist and cut in 1 mm2PO4, 1.8 NaH2PO4) or artificial cerebral spinal fluid (aCSF)  at pH 7.2–7.4. Solutions of different dopamine concentrations in 1 × PBS or 1 × aCSF were prepared by diluting the stock solutions from zM (10–20) to nM (10–9). Baseline transconductance for EG–gFETs in each gMTA aptasensor was measured in PBS or aCSF not containing dopamine by applying a VDS of 1 mV, and sweeping VGS between 0 and 1 V. Following baseline measurements, 20 μL samples of each dopamine concentration in either buffer were incubated in the gMTAs. Between samples, gMTAs were rinsed with DI water, and transconductance measurements were taken in 1 × PBS or 1 × aCSF accordingly, with the same voltage parameters used for baseline acquisition. More than 500 EG–gFETs from over 30 gMTAs provided measurements for the PBS and aCSF calibration curves, with each concentration for each electrolytic buffer being incubated in at least 4 gMTAs (minimum 80 EG–gFETs per concentration per buffer).Dopamine hydrochloride  in powder form was first prepared into a stock solution of 10 mM in either phosphate-buffered saline (PBS)  to 10 fM (10–14), prepared as described above, were adjusted for a final pH of either 6.4 or 8.4 by adding droplets of 2 M HCl or 0.5 M NaOH respectively. Sample incubation and transconductance measurements were performed as described above.For the pH experiments, dopamine dilutions from 0.1 aM (10–9) concentration. Then, 20 μL samples of each solution were incubated in the gMTAs. After DI water rinse, transconductance measurements were taken in 1 × PBS with the same voltage parameters described above. Samples from each solution were incubated in at least 2 gMTAs (minimum 40 EG–gFETs per solution).L-DOPA , L-Tyrosine, and ascorbic acid were diluted in 1 × PBS to 1 nM  were injected with reserpine  dissolved in 1% glacial acetic acid and diluted in 0.9% saline. Control mice (n = 6) were injected with vehicle solution not containing reserpine. 8 h post-administration, all mice were anesthetized with avertin , placed in a stereotaxic frame for head fixation, and CSF was collected by DS of 1 mV and sweeping VGS between 0 and 1 V.For dopamine detection in CSF, frozen samples were thawed on ice, and 2 µL samples were placed directly on the gMTAs. For every gMTA, transconductance measurements were first acquired for a CSF sample from a reserpine-treated animal incubated for 10 min. Following rinsing with PBS, a sample from a control animal was incubated in the same gMTA for 10 min. The EG–gFETs transconductance was measured by applying a V–18) to 10 nM (10–8). Each 20 µL sample was incubated for 20 min in one gMTA and then rinsed with 1 × PBS. Transconductance measurements were taken before rinsing with the same voltage parameters described above.Previously dissected striatum brain samples were first thawed on ice for dopamine detection in brain homogenate. Samples from two brains  were pooled in a single Eppendorf tube with 1 × aCSF (pH 7.4) added at 5 μL/mg for homogenization with a brain tissue homogenizer. Samples were then centrifuged at 14,000 rpm, for 15 min at 4 °C. Dopamine hydrochloride diluted in 1 × aCSF was added to 10 µL of homogenate supernatant samples from reserpine-treated animals on a 1:1 volume ratio for final dopamine concentrations ranging from 1 aM  or Matlab ver. 2021a (Mathworks). Statistical details can be found in figure legends.Additional file 1: Figure S1. Raman spectrum of CVD grown single-layer graphene. Figure S2. Averaged response from measurement replicates of a single gMTA chip. Figure S3. XPS peak fitting for PBASE and PBASE + aptamer samples. Figure S4. Blank samples measurements in PBS. Figure S5. Stability of gMTA measurements. Figure S6. Dopamine attomolar detection with short incubation time.


Mikania micrantha). The social-ecological systems approach reveals that household perceptions of the presence of M. micrantha were more strongly associated with resource collection decisions than the actual ecologically measured presence of the plant. We explore the policy implications of our findings for PAs and propose that employing a social-ecological systems approach leads to conservation policy and scientific insights that are not possible to achieve with social or ecological approaches alone.Protected areas (PAs) are critical for achieving conservation, economic and development goals, but the factors that lead households to engage in prohibited resource collection in PAs are not well understood. We examine collection behaviours in community forests and the protected Chitwan National Park in Chitwan, Nepal. Our approach incorporates household and ecological data, including structured interviews, spatially explicit data on collection behaviours measured with computer tablets and a systematic field survey of invasive species. We pair our data with a framework that considers factors related to a household’s demand for resources, barriers to prohibited resource collection, barriers to legal resource collection and alternatives to resource collection. The analysis identifies key drivers of prohibited collection, including sociodemographic variables and perceptions of an invasive plant ( Globalleasoning . PAs noweasoning . Althougeasoning . These feasoning . One impThere are challenges to studying why some people abide by rules within PAs while others disregard them. First, it is difficult to obtain direct reports on rule violations from violators because violations are often either legally prohibited or socially unacceptable. Prior work has typically relied on indirect measures, although some studies have engaged in direct questioning or observation of violators e.g., . Second,PAs are complex social-ecological systems in which multiple pathways and mechanisms affect each other . Due to Mikania micrantha in community forests; (2) collect institutional data from community forests managers on the perceived spatial distribution of M. micrantha; (3) collect ecological data on the spatial distribution of M. micrantha; and (4) examine the impacts of these human, institutional and ecological factors on prohibited collection. Each of our data sources benefits from: (1) direct measurement, (2) spatial precision and (3) representative sampling. We focus on M. micrantha because it has been called the ‘most serious weed in the tropical and subtropical areas of Nepal’ (The objectives of this research were to: (1) collect human data on the household drivers of prohibited collection and perceptions of f Nepal’ , and our2 western Chitwan Valley is home to over 200 000 individuals  and endangered Bengal tiger (Panthera tigris tigris)  . The For tigris) . This ar tigris) .M. micrantha, Chromolaena odorata and Lantana camara   . M. micrng event . M. micr-adapted , and it -adapted . TogetheTo understand prohibited collection, we collected data across multiple domains: human, ecological and institutional. In each domain, we ensured that our data were direct, spatially explicit and representative. Human subjects research was approved by the Institutional Review Board at Penn State University (Study #00005177).Household data were collected in autumn 2014. Social surveys included questions about the household, including structure, ethnicity, number of animals, area of land farmed, whether the household buys fodder and fuelwood and experiences with invasive species. To assess the spatial aspect of collection behaviours, a knowledgeable household member used an interactive tablet app that contained touch-enabled satellite imagery of the Chitwan area. The respondent circled areas where household members had collected different types of forest resources in the past year. Using tablets to collect spatial data in this population has been shown to be accurate . The tabAlthough the household survey interviewed 1235 households, our analysis uses 1036 households that resided in areas eligible for membership in one of 21 local CFs; we refer to these areas as ‘CF catchment areas’. Of the 21 CFs, 17 are within buffer zone CFs (BZCF) under the jurisdiction of CNP . The remaining four CFs are under the jurisdiction of the District Forest Office (Department of Forest). Although all share governing principles, the BZCFs receive additional financial resources from CNP for forest management, compensation for damage by wildlife and community development activities. c. 400 households each and sub-wards were randomly sampled; third, chosen sub-wards were enumerated to create a household sampling frame and households were randomly sampled. The household response rate for the face-to-face survey interview was 98%.Households were selected through a three-stage process: first, wards (administrative units) in catchment areas were randomly sampled proportionate to population size in the 2011 Census; second, chosen wards were divided into equal sub-wards of M. micrantha, C. odorata and L. camara and percentage cover of the three most dominant herbs and tree species. In total, 2219 plots were surveyed.The ecological data were collected from 2013 to 2015 using a systematic vegetation survey throughout the CFs that surround the household settlements: 11 forests were surveyed in 2013 (August–November), 8 in 2014 (September–November) and 2 in 2015 (September–October). In the CFs, parallel transects were drawn every 200 m. Along each transect, one plot (composed of two 5 m × 5 m areas) was sampled every 50 m. Variables collected included canopy cover, evidence of disturbance, presence as well as percentage cover of the invasive species We measured both self-governance and market institutions. A representative from each of the 21 CF management committees was interviewed in 2014. Surveys measured management techniques, perceived challenges and experiences with invasive species. In addition, the representatives used a tablet to indicate areas of invasive species presence in their CF. Market organizations, governmental organizations and NGOs were enumerated in terms of the presence of organizations such as shops, schools, health clinics, restaurants and factories. Project staff walked all roads in each sub-ward and used a custom-designed tablet app with integrated GPS to enumerate the locations of all organizations. In the 21 catchment areas, 2335 such organizations were identified.Prohibited collection in CNP over the past year was directly collected from a household respondent. If the respondent drew a collection area for fuelwood or fodder (the most commonly collected resources) that overlapped with CNP boundaries, the household was coded 1 on prohibited collection and 0 otherwise.We expected that the likelihood that a household engaged in prohibited collection would vary according to the following factors derived from our observations and existing literature : (1) demM. micrantha. Reflecting the multiple dimensions through which invasive species may increase prohibited collection, we measured M. micrantha in three ways: household perceptions of M. micrantha spread; the percentage of the CF covered by M. micrantha as indicated in the management committee survey; and the percentage of a CF’s plots with any M. micrantha . Alternatives to resource collection were hypothesized to lower the likelihood of prohibited collection. Households with more alternatives were those with greater incomes, that report purchases (in addition to or instead of collection) of fuelwood and animal feed and that are in areas with a high density of market  organizations where alternatives to resource collection were readily available. The demand for forest resources (fodder and firewood) was hypothesized to be positively associated with prohibited collection. Variables representing the demand for forest resources included the number of household members, number of dairy animals and size of farmland. Barriers to prohibited resource collection were hypothesized to reduce prohibited collection. This variable was measured according to the distance from the household to the nearest CNP boundary; greater distance made collection in CNP less convenient. Barriers to legal resource collection were expected to increase prohibited collection. Barriers included minority ethnicity (who are sometimes discouraged or excluded from CF membership), being in a catchment area with a small CF and being a member of a CF with a higher presence of the invasive species Although ethnic groups are diverse, for analysis we adopted five categories from the literature : (1) BraR version 4.0.4  and density of market  organizations. The sampling of households was clustered by CF catchment area. To accommodate for this, we included a random intercept for catchment area in our model. In random-effects logistic regression models, the coefficient can be interpreted as the relationship between the independent variable and the log odds of prohibited resource collection. A positive coefficient means a variable increases the log odds of prohibited collection; a negative coefficient decreases the log odds of prohibited collection. The models were estimated in on 4.0.4  using thn 1.1–26 .c. 11% , while others had no land. On average, households were c. 2.25 km from the closest CNP boundary, although this distance varied from 50 m to nearly 10 km. Perceived M. micrantha invasion in a household’s assigned CF (based on the catchment area) varied across households. Approximately 20% of households thought M. micrantha was decreasing or not changing and c. 20% thought it was increasing slowly, but the largest group, at 50%, thought it was increasing rapidly; c. 10% answered ‘did not know’ to this question. When asked to circle the areas in which they believed M. micrantha was present, the households’ CF managers indicated areas that, on average, it encompassed 47% of their forest. As measured in our 2219 ecological plot surveys, M. micrantha was present, on average, in 14% of plots in the CF of which a household was a member. The managers and plot survey reports differed greatly.There was diversity in the factors that could increase or decrease a household’s tendency to collect resources in CNP . Some hoWe present our model with all predictors , but we The amount of land farmed, number of dairy animals  owned and household size were not associated with the log odds of prohibited collection . The logM. micrantha invasion in a CF was significantly associated with the log odds of prohibited collection. Compared to households that said M. micrantha was decreasing or staying the same (the reference group), households that thought M. micrantha was rapidly increasing were significantly more likely to engage in prohibited resource collection. The frequency of M. micrantha in plots in the household’s assigned CF, as measured in our ecological surveys or in the CF management committee tablet surveys, was not significantly associated with prohibited collection  did not predict prohibited collection. Human behaviour is often motivated by perceptions and attitudes . Conservation policies that address unequal legal access to natural resources may yield beneficial outcomes. Differences between specific policies may be less important to the success of the policy than having policies that are linked to local intrinsic motivations and social justice issues . A conseConservation policies often displace social-environmental pressures to surrounding lands, which may not be legally protected by the formal policies of adjacent PAs . These sM. micrantha as rapidly increasing did not always align with the ecological data on M. micrantha. Local officials with broader knowledge of M. micrantha may be able to guide households in collecting forest resources in areas with less M. micrantha, but only if households have established trust with these officials (M. micrantha, are critical to reducing prohibited natural resource collection in PAs (One possibility for addressing inequality in access to forest resources in Chitwan is creating a programme to build local capacity – in terms of both logistical resources and shifting social norms – so as to redistribute resources between neighbouring CFs to provide for low-income households, for recently established households and for those facing other hardships. Our social-ecological systems approach also revealed that it is critical for managers and stakeholders to consider both social and ecological data in order to fully understand people’s resource collection decisions. This is important because household perceptions of fficials . Thus, sn in PAs . Communin in PAs  in orderM. micrantha. Thus, supporting relationship-strengthening among households and conservation officials and capacity-building for equitable resource access should reduce prohibited collection.Individual conservation programmes are not capable of overturning or reversing structural issues such as multidimensional poverty and historical mistrust between officials in power that often drive prohibited natural resource collection . Any pol


H-imidazol-2-yl)-4-phenol (PIMH) in the presence of various nitrogen containing compounds (N-compounds). Molecularly imprinted polymer nanofibers show selectivity for various target model nitrogen-containing compounds with adsorption capacities of 11.7 ± 0.9 mg g−1, 11.9 ± 0.8 mg g−1 and 11.3 ± 1.1 mg g−1 for quinoline, pyrimidine and carbazole, respectively. Molecular modelling based upon density functional theory (DFT) indicated that hydrogen bond interactions may take place between the lone-pair nitrogen atom of model compounds (quinoline and pyrimidine) and the –OH and –NH groups of the PIMH nanofibers. The adsorption mode followed the Freundlich (multi-layered) adsorption isotherm, which indicated possible nitrogen–nitrogen compound interactions. Molecularly imprinted polymer nanofibers show potential for the removal of nitrogen-containing compounds in fuel.Molecularly imprinted polymer (MIP) nanofibers were prepared by the electrospinning of poly 2-(1 H-imidazol-2-yl)-4-phenol nanofibers fabricated via electrospinning displayed excellent selectivity adsorption capacities nitrogen containing compounds (N-compounds) in hydro-treated fuels.Molecularly imprinted poly-2-(1 Refinery feedstocks in general are extremely complicated chemical mixtures in which each heteroatom is present in the form of literally hundreds of different compounds. In general, the presence of organonitrogen compounds in fuel results in fuel instability during storage, due to the formation of gums, colours and sediments, compounds, such as quinoline and related molecules are capable of binding strongly on catalyst surfaces, hence, deactivating refining catalysts.2–7 The most harmful effect of nitrogen compounds in fuel is the emission of NOx into the environment which is a major source of pollution that causes many environmental hazards like acid rain, greenhouse effect and photochemical smog.Fuel oil is the major source of energy for industrial machines and most vehicles in many countries of the world, and it is obtained mainly from fossil sources.8 Due to the harm posed by these gases, the US EPA aimed at improving air quality mandated the reduction of nitrogen content in diesel fuel to ultra-low levels of <1 mg L−1,9 South Africa is also driving toward achieving the ultra-low levels.New severe environmental regulations call for much lower levels of heteroatom-derived pollutants, organosulfur compounds and organosulfur compounds and this has stimulated an intensification of research and development efforts toward new or improved processes.ca. 70% nitrogen removal, corresponding to a final content of about 0.5 wt% N at typical operating conditions .10–13 This indicated that the HDN technique is limited in eliminating organonitrogen compounds, thus requires alternative/complementary techniques such as extraction denitrogenation (EDN), oxidation denitrogenation (ODN), adsorptive denitrogenation (ADN), and biodenitrogenation are currently under study.Hydrodenitrogenation (HDN) is currently being employed to eliminate organonitrogen compounds in fuels. These extensively used technologies enabled oil refineries throughout the world for many years to systematically reach a ceiling of 14 This method suffers from the fact that other compounds can also be extracted along with the organonitrogen compounds. Oxidative denitrogenation (ODN), an alternative/complementary technique to the HDN, involves the oxidation of nitrogen-containing compounds to form oxygenated derivatives. Ishihara et al.15 reported that nitrogen-containing compounds give N-oxide and other products due to cycle cleavage as well as polymer formation due to the presence of radicals. Ding et al.,16 recently reported the mild oxidation of pyrimidine to N-oxides with H2O2 by vanadium-substituted polyoxometalate. However, the reaction did not proceed to the removal of the N-oxides. Recently, our research group17 described a technological method for the removal of nitrogen compounds from fuels, via oxidation and extractive adsorption. Oxidative denitrogenation is an expensive technique which requires the development of additional plant in the refining industry.Extractive denitrogenation or liquid–liquid extraction is another method that has been applied in the removal of organonitrogen compounds in fuel.18–21 with less selectivity in the removal of organonitrogen compounds in fuels. However, sorbent materials such as molecularly imprinted polymers (MIPs) fabricated through imprinting of templates unto polymers suffice as potential adsorbents for the adsorption of these compounds.22 Molecular imprinting of polymers is a technique employed for the introduction of recognition sites into polymeric matrices via the formation of bonds between the imprinting molecule (template) and functional groups within the polymer network.22 Hence, the need to develop smart polymer nanofiber-based adsorbents [molecularly imprinted polymers (MIPs)] with large surface area-to-volume ratio for the selective removal of sulfonated compounds in fuels.22Adsorptive denitrogenation (ADN) is about the most recent method that is being applied to remove organonitrogen compounds in fuel oil. So far, many adsorbents such as activated carbon, zeolites, silica, ion-exchange resins have been used for the ADN,H-imidazol-2-yl)-phenol (PIMH) nanofibers for the first time by employing the solid phase extraction technique. A combined experimental and computational study was adopted to gain a fundamental understanding of the possible interactions responsible for adsorption. Complete diesel fuel analysis prior and after adsorption was achieved through the use of LECO Pegasus GC × GC-HRT.In this study, we describe the selective adsorption of organonitrogen compounds  over molecularly imprinted poly 2- (AIBN), tetrahydrofuran (THF), nitrogen heterocyclic compounds-quinoline, carbazole and pyrimidine were purchased from Sigma Aldrich, Germany. Acetonitrile (HPLC grade) and methanol (HPLC grade) were purchased from Merck, South Africa.H-imidazol-2-yl)-4-phenol, was synthesized in a similar method reported by Sellergren et al.,23 with some modifications. This is presented in the ESI, Section A.†The compound, poly 2-(1H-imidazol-2-yl)-4-vinyl phenol, 0.02 g of AIBN and 2 mL of toluene were stirred in 10 mL vial. The mixture was polymerized under argon at 70 °C for 8 h as shown in synthesis H-imidazol-2-yl)-4-phenol, was dissolved in THF and precipitated out with methanol, filtered and washed with methanol.2 g of 2-(1H-imidazol-2-yl)-4-vinyl phenol nanofibers were fabricated via electrospinning of poly 2-(1H-imidazol-2-yl)-4-phenol solutions. Polymer solution for electrospinning was prepared by dissolving 2.2 g of poly 2-(1H-imidazol-2-yl)-4-phenol in 4 mL of THF : DMF (1 : 1). The mixture was gently stirred overnight at room temperature to obtain a homogeneous solution for electrospinning. For molecularly imprinted nanofibers, 1 mL (10 mM in acetonitrile) of the respective nitrogen containing compounds containing 20 μL triton X-114 (surfactant agent) was added drop-wise to the dissolved poly 2-(1H-imidazol-2-yl)-4-phenol solution. The mixture was further stirred for 2 h to achieve the desirable solution homogeneity for electrospinning (nitrogen containing compounds were not employed in the fabrication of non-imprinted nanofibers).Imprinted and non-imprinted poly 2- imprinted within the nanofibers were removed by washing the nanofibers via Soxhlet extraction with a solution mixture of warm-to-hot methanol and acetonitrile (1 : 1) until no templates was detected on the GC.Polymer solutions were respectively poured into a 25 mL syringe attached to a needle connected to the positive electrode of a high voltage power supply . A syringe pump  was used to supply a constant flow of polymer solution from the syringe during the electrospinning process. A voltage of 20 kV was applied to the polymer solution which was pumped at a flow-rate of 0.3 mL hH-imidazol-2-yl)-4-phenol nanofibers (50 mg) into screw-capped vials containing 3 mL of nitrogen containing compounds (120 mg L−1) alongside other molecules. The screw-capped vials containing nitrogen compounds were left under mechanical agitation 100 rpm for 12 h. Progress in the adsorption of the various nitrogen containing compounds were followed by withdrawing aliquots for measurement after every hour. Adsorption capacity, qe (mg g−1) was calculated from Co, Ce, W and V are the initial concentration (mg L−1), equilibrium concentration (mg L−1), dry weight of nanofibers (g) and solution volume (L) respectively. Conditioning of adsorbents was carried-out by pre-wetting adsorbents with solvents employed in dissolving the nitrogen compounds.Nitrogen compounds adsorption studies were performed under batch conditions by weighing a known mass of molecularly imprinted poly 2-(1H-imidazol-2-yl)-4-phenol nanofibers employed for adsorption were regenerated for re-usability by washing nanofibers with warm solvent mixture of acetonitrile and methanol (1 : 1).Molecularly imprinted poly 2-; and then stored for the next experiment. A typical solid phase extraction (SPE) manifold employed for the study is presented in Fig. S1.†The molecularly imprinted nanofibers column method was tested with model solutions prior to the selective adsorption and determination of N-compounds in fuel. For N-compound adsorption, 3 mL solution containing known amount of N-compounds in model fuel was employed. The column was preconditioned by passing hexane solution under gravity. After passing of this solution ending, the column was loaded with N-compounds solution. The adsorbed N-compounds on the column were eluted with 5–10 mL portion of methanol : acetonitrile (1 : 1). The eluent was analysed for the determinations of the various N-compound concentrations by GC-FID and GC × GC-HRT.24 Van 't Hoff experiments for all model organonitrogen compounds were carried out at 30, 35, 40 and 45 °C by using batch adsorption process. Aliquots of analyte solutions are withdrawn at every 20 min interval and analysed by using a GC-FID. Thus, ΔH° can be determined from the slope of the linear Van't Hoff plot i.e. in Kadversus (1/T).24 Isothermal Titration Calorimetry (ITC) studies was also conducted and presented in the ESI (Section B).H-imidazol-2-yl)-4-phenol (PIMH) and the various nitrogen containing compounds  were modelled and discussed in the ESI, Section B.†The Van 't Hoff plot was used to determine the thermodynamic parameters such as enthalpy, entropy and Gibbs free energy of adsorption process.−1) were run on Bruker, Tensor 27 platinum ATR-FTIR spectrometer. The 1H NMR spectra of ligands and monomer were recorded on a Bruker 400 MHz spectrometer in DMSO-d6. Thermogravimetric analyses of imprinted and non-imprinted nanofibers were performed using Perkin-Elmer TGA 7 thermogravimetric analyser (TGA). Typically, the samples were heated at a rate of 10 °C min−1 under a constant stream of nitrogen gas. The polymer nanofibers were imaged using a TESCAN Vega TS 5136LM scanning electron microscope (SEM). Before images were taken; the various 2-(1H-imidazol-2-yl)-4-phenol nanofibers were gold coated to prevent surface charging and to protect the surface material from thermal damage by the electron beam. Nitrogen adsorption/desorption isotherms were measured at 77 K using a TriStar II 3020 3.02 Analyzer by Micromeritics Instrument Corporation to determine surface area and porosity of the nanofibers. Prior to each measurement, nanofibers were degassed at 60 °C for 24 h. The BET surface area, total pore volume and pore size distribution were calculated from these isotherms. Adsorption studies for model compounds was monitored by employing an Agilent 7890A gas chromatograph fitted with flame ionization detector (GC-FID). The GC conditions for the adsorption analyses was started with an oven temperature of 50 °C ramping to 80 °C for 2 min, and then increased to 300 °C at a rate of 20 °C min−1, and finally held for 1 min.FT-IR spectra  at 250 °C; primary column: Stabilwax (Restek), 30 m × 250 μm (0.25 μm); secondary column: Rxi-5 (Restek), 1.5 m × 100 μm (0.1 μm); carrier gas: helium, 1.2 mL per minute constant flow; primary oven program: 40 °C (0.1 minute) to 260 °C (78.4 min) at 3 °C per minute; secondary oven program: 45 °C (0.1 minute) to 265 °C (56 minute) at 3 °C per minute; modulator offset: 15 °C; modulation frequency: 8 seconds; hot time: 2 seconds; MS: LECO Pegasus 4D GC × GC-HRT; ionization: electron ionization at 70 eV; source temperature: 250 °C; stored mass range: 30 to 500 u; acquisition rate: 100 spectra per second. PBM data was replaced with SVG by xgml2pxml:<glyph-data id="z.dbd" format="PBM" resolution="300" x-size="8" y-size="10" xml:space="preserve">00000000000000000000000000000000111111110000000011111111000000000000000000000000</glyph-data><svg xmlns="http://www.w3.org/2000/svg" version="1.0" width="13.200000pt" height="16.000000pt" viewBox="0 0 13.200000 16.000000" preserveAspectRatio="xMidYMid meet"><metadata>Created by potrace 1.16, written by Peter Selinger 2001-2019</metadata><g transform="translate scale" fill="currentColor" stroke="none"><path d="M0 440 l0 -40 320 0 320 0 0 40 0 40 -320 0 -320 0 0 -40z M0 280 l0 -40 320 0 320 0 0 40 0 40 -320 0 -320 0 0 -40z"/></g></svg>N), amine (–NH), (–CN–C–) and (CC) groups were observed for all nanofibers. FT-IR analyses of the imprinted compounds are as follows: carbazole-imprinted nanofibers FT-IR (cm−1): 3293 ν(O–H), 1650 (–NH) bend, 1632 ν(CN), 1626 ν(CN–C), 1507 ν(CC); pyrimidine-imprinted nanofibers FT-IR (cm−1): 3223 ν(O-H), 1650 (–NH) bend, 1623 ν(CN), 1631 ν(CN–C), 1503 ν(CC); quinoline-imprinted nanofibers FT-IR (cm−1): 3228 ν(O–H), 1630 (–NH) bend, 1632 ν(CN), 1623 ν(CN–C), 1506 ν(CC).The FT-IR spectra of non-imprinted nanofibers, carbazole-imprinted nanofibers, pyrimidine-imprinted nanofibers and quinoline imprinted nanofibers are all presented in Fig. S2 of ESI data.A weight loss of loosely-bound solvents within the nanofibers were observed at temperatures below 120 °C. All nanofibers presented a single-step decomposition pattern which occur between 375–450 °C.NIP nanofibers presented a single-step decomposition pattern which occur between 395–440 °C. An observed 3% weight loss around 120 °C was assigned to loosely-bound (intermolecular) solvent within the nanofibers. The decomposition of non-imprinted nanofibers backbone only began to occur at temperatures of around 370 °C to about 440 °C, hence resulting in a total polymer weight loss of 92%, after which the carbon residue remained. The TGA profile of NIP was presented alongside the profiles reported for quinoline-imprinted nanofibers (QUNMIP), pyrimidine-imprinted nanofibers (PYMMIP) and carbazole-imprinted nanofibers (CARMIP) for a better comparison .The quinoline-imprinted nanofibers gave similar decomposition patterns as likened with NIP nanofibers (one step decomposition: 386–440 °C). A 4% weight loss observed at around 110 °C was attributed to loosely-held (intermolecular) solvent molecules within the nanofibers. Followed by a rapid decomposition of quinoline-imprinted polymer backbone at 370 °C to a temperature of about 450 °C . A totalThe pyrimidine-imprinted nanofibers (PYMMIP) nanofibers presented a distinct weight loss between 380 and 430 °C. Pyrimidine-imprinted nanofibers displayed high stability to around 300 °C, this confirmed that the nanofibers were dry and free of solvents. Gradual breakdown of polymer backbone only began to occur at temperatures between 390 and 430 °C, with a total weight loss of 96% .The carbazole-imprinted nanofibers (CARMIP) presented one distinct weight losses at around 390 °C and 430 °C. A 2% weight loss observed at around 110 °C was attributed to loosely-bound solvent within the nanofibers. Followed by a rapid decomposition of quinoline-imprinted polymer backbone at 370 °C to a temperature of about 450 °C . A totalvia TGA analysis are in the order of; pyrimidine-imprinted nanofiber > carbazole-imprinted nanofibers > quinoline imprinted nanofibers.The thermal stabilities of molecularly imprinted nanofibers obtained The SEM micrographs of non-imprinted and imprinted nanofibers after washing and drying are presented in Energy Dispersive Spectroscopy (EDS) images for the various non-imprinted and imprinted nanofibers after washing and drying are presented in Fig. S3.A Brunauer–Emmett–Teller (BET) model was used to calculate the specific surface area and a Barrett–Joyner–Halenda (BJH) model was used to calculate the pore volume distribution and the average pore size of (A) non-imprinted nanofibers, (B) quinoline-imprinted nanofibers (QUNMIP), (C) pyrimidine-imprinted nanofibers (PYMMIP) and (D) carbazole-imprinted nanofibers (CARMIP).A decrease in the surface area of the nanofibers upon imprinting was due to pores being created by organonitrogen compounds as seen in the reported pore sizes . The resH-imidazol-2-yl)-4-phenol (PIMH) nanofibers. 50 mg of the imprinted adsorbents were added to vials and mixed with 3 mL solution mixture of nitrogen containing compounds , dibenzothiophene and naphthalene (120 mg L−1 each).Adsorption assays were carried out to evaluate the loading capacity and selectivity of imprinted poly 2- quinoline-imprinted nanofibers (QUNMIP) presented 11.7 ± 0.9 mg ge Fig. S5 (ii) pyre Fig. S6 and .The non-specific binding nature on non-imprinted nanofibers gave rise to the non-selective adsorption reported as compared to the imprinted nanofibers whose binding sites alongside cavities created via subtraction of the unabsorbed N-compounds indicated that concentrations of 118.8, 117.3 and 116.4 mg L−1 for pyrimidine, quinoline and carbazole, respectively, are required for complete adsorption.Theoretical calculation k) is defined as the ratio of the adsorption capacity of imprinted nanofibers (QMIP) to the adsorption capacity of the non-imprinted nanofibers (QNIP). The higher the value of k, the better is the imprinting effect.where k is the imprinting factor, QNIP (mg g−1) is the adsorption capacity of the non-imprinted nanofibers and QMIP (mg g−1) is the adsorption capacity of imprinted nanofibers.The imprinting constant (k) values for quinoline-imprinted nanofibers is 18.92, pyrimidine-imprinted nanofibers is 18.56, and carbazole-imprinted nanofibers is 22.16, respectively  contained in 3 mL of 120 mg L−1 N-compounds solution.qe and qt (mg g−1) are the amounts of N-compounds adsorbed on the adsorbent at equilibrium and time t, respectively. K1 (h−1) is the pseudo-first-order adsorption rate constant and was calculated by plotting the log(qe − qt) versus t (R2), carbazole, quinoline and pyrimidine fitted the pseudo-first-order model. The pseudo-second-order plot is presented in Fig. S8.†The kinetic mechanism that controls the adsorption process under batch study was monitored by using pseudo-first-order model  and pseuversus t . The pseqe (mg g−1) and Ce (mg g−1) are the amount adsorbed at equilibrium and the equilibrium concentration, (Qm), is the theoretical maximum adsorption capacity at monolayer (mg g−1), and Kd is the Langmuir constant (related to the affinity of adsorption sites).26 Freundlich constants k and n indicating adsorption capacity and intensity respectively were determined from the linear plot of log qe against log Ce. Freundlich isotherm indicated a multiple layered adsorption on adsorbents, which may possibly infer nitrogen compound-nitrogen compound interactions on the adsorbent. While Langmuir equation obtained from a plot of Ce/qe against Ce is probably proof of chemical adsorption, which may usually mean monolayer adsorption on the surface of adsorbents.26The adsorption behaviour of nitrogen containing compounds on imprinted nanofibers was followed using the Langmuir and Freundlich isothermal equations .45where R2, n’ value lies within the range 1 to 10, thus indicating that adsorption on the nanofibers are favourable.26 The Langmuir parameters plot is presented in Fig. S9.†From the plots, Freundlich adsorption equation fitted better  for N-compounds are shown in  observed on all interactions indicated feasibility and spontaneity of the adsorption processes.25 The negative ΔH° values observed for all nitrogen containing compounds pyrimidine, carbazole and quinoline confirmed the exothermic nature of the overall-sorption process. The positive value of ΔS° observed for all nitrogen containing compounds suggests increased randomness at the solid/solution interface with some structural changes (in the adsorbate and adsorbent) as well as the binding affinity of the various nitrogen containing compounds to the imprinted nanofibers.The result obtained from Van't Hoff plot is in agreement with the data obtained through DFT studies and isothermal titration calorimetry (ITC)  of the nitrogen compounds and Ce was the eluted concentration of the nitrogen compounds. The linear capacity of the column (ns), the capacity factor of the solute (k) and percentage recovery (r) are calculated from 22,26 and presented in Vo is the initial volume of the analyte (nitrogen solutions), breakthrough volume (VB), retention volume (VR) and hold-up volume (VM) of the analyte (nitrogen solutions).From the adsorption curve, the maximum amount of nitrogen containing compounds retained falls within the range of 0.9–1.5 mL (900–1500 μL). The breakthrough curves of the N-compounds solutions obtained are presented in A recovery rate in the order of pyrimidine > quinoline > carbazole was observed for the continuous flow study.27 Solid phase extraction (SPE) is an increasingly useful sample preparation technique. The rebinding adsorption capacities of imprinted nanofibers decreased significantly for all nitrogen compounds as we move from 1st adsorption cycle to the 3rd cycle for carbazole  technique. Fig. S10, quinoli Fig. S10 and pyri Fig. S10. This reH-imidazol-2-yl)-4-phenol polymer nanofibers on solid phase extraction (SPE). Prior to denitrogenation, alkylated organonitrogen compounds in diesel were identified by employing LECO Pegasus 4D GC × GC-HRT  as adsorbent. Adsorption proceeded under SPE manifold by conditioning imprinted nanofibers at a vacuum pressure of 20 in Hg with a solution of hexane followed by loading the hydrotreated diesel (1 mL hydrotreated diesel in 2 mL of hexane). Cyclohexane was employed to wash interfering molecules from the sorbent and finally N-compounds were eluted by using a mixture of acetonitrile : methanol (1 : 1).GC × GC-high-resolution TOF-MS surface plot confirmed a reduction in the presence of alkylated organonitrogen compounds in the hydrotreated fuel . Accordivia hydrogen bond formation with the polymer nanofibers. Imprinted nanofibers was unable to eliminate 3--9-methylcarbazole completely due to the highly alkylated nature of the compound, thus, inhibiting interactions with the active sites of the adsorbent.As observed in 28,29 They observed that MOFs with high porosity absorbed higher concentrations of nitrogen containing compounds (NCCs).29–31 A study reported by Nuzhdin et al.29 indicated that a total of 1.3 mmol of nitrogen containing compounds (NCCs) was removed by 1 g of MIL-101(Cr). Results obtained with the use of molecularly imprinted nanofibers in this study could be said to be comparable with the results reported by Nuzhdin et al.29 and some others reported in the literature.29 The use of poly 1,1′-binaphthyl-2,2′-diol nanofibers for the adsorption of quinoline and isoquinoline in a model simulated fuel presented an adsorption capacity of 2.2 and 2.4 mg g−1, respectively.32 These capacities falls short of the value reported in the current study, hence, confirming an improvement in the fabricated material through imprinting process. Therefore, the use of molecularly imprinted nanofibers as adsorbent in the adsorption of NCCs offers improved surface area, porosity (cavities), adsorption capacities and selectivity.31Many solid adsorbents have been employed for denitrogenation of fuels and these adsorbents have proven to be worthwhile in terms of general performance. The use of imprinted nanofibers is relatively new and limited literature exists. However, several investigations of ADN using solid sorbents such as MOFs have been reported.H-imidazol-2-yl)-4-phenol were predicted by molecular interaction studies using B3LYP functional with a basis set 6-311G++ using the Gaussian09 software  under tight convergence criteria.33 Further details on DFT calculations such as HOMO–LUMO band gap, hardness (η), softness (σ), electronegativity (χ), and chemical potential (μ) calculations are provided in ESI (Section B).†The atomic level interaction of the various nitrogen containing compounds  with poly 2-(1H-imidazol-2-yl)-4-phenol to understand the mechanism of adsorption. Studies reported includes HOMO and LUMO energy positions, HOMO–LUMO energy gap (ΔE), hardness (η), softness (σ), electronegativity (χ) and chemical potential (μ) of the adsorbent and adducts.34DFT calculations was carried out for the interaction of N-compounds  with 2-(1H-imidazol-2-yl)-4-phenol indicated that the HOMO position centers around the –OH and –NH and aromatic rings of the ligand, 2-(1H-imidazol-2-yl)-4-phenol, while the LUMO position originates around the imidazoline ring.Molecular orbital energy diagram of 2-(1H-imidazol-2-yl)-4-phenol, while LUMO centers mostly around each nitrogen containing compounds (H-imidazol-2-yl)-4-phenol and N-compounds  mainly occur through electron donation from the HOMO to the LUMO (H-imidazol-2-yl)-4-phenol and N-compounds as well as hydrogen bonding was observed.Upon interacting with N-compounds , HOMO position of the adducts originates from 2-(1ompounds . This clthe LUMO . The posH-imidazol-2-yl)-4-phenol and carbazole, 2-(1H-imidazol-2-yl)-4-phenol and quinoline and 2-(1H-imidazol-2-yl)-4-phenol and pyrimidine is presented in Images showing the HOMO–LUMO positions of 2-(1H-imidazol-2-yl)-4-phenol, are −5.35 and 0.49 eV, respectively. High ionization potential is indicated by low HOMO energy (better electron donor), while high electron affinity is indicated by high LUMO energy (better electron acceptor). The energy gap of 2-(1H-imidazol-2-yl)-4-phenol which depends on the HOMO and LUMO energies was observed to be 4.88 eV.The HOMO–LUMO gap describes the stability and resistance of molecules, and it also predicts activity between species by providing the electrical transport properties as well as electron carrier and mobility in molecules. The HOMO and LUMO energies of 2-(1H-imidazol-2-yl)-4-phenol resulted in a decrease in HOMO–LUMO energy gap when compared to the HOMO–LUMO gap of the nitrogen compounds, thus further indicating interactions. 2-(1H-imidazol-2-yl)-4-phenol–carbazole adduct (PIMH–CAR), 2-(1H-imidazol-2-yl)-4-phenol–pyrimidine adduct (PIMH–PYM) and 2-(1H-imidazol-2-yl)-4-phenol–quinoline adduct (PIMH–QUN) all presented lower HOMO–LUMO gap as compared to the values obtained for carbazole (CAR), pyrimidine (PYM), quinoline (QUN) and 2-(1H-imidazol-2-yl)-4-phenol (PIMH) (Table S228 The order of N-compound hardness and softness is pyrimidine (PYM) < quinoline (QUN) < carbazole (CAR), thus, indicating that pyrimidine is more reactive and carbazole is least reactive. Molecules with large electronegativity can be considered as stronger electron acceptors.34 Electronegativity data agrees with the HOMO–LUMO diagram which indicates that electrons are donated by 2-(1H-imidazol-2-yl)-4-phenol (PIMH) and accepted N-compounds . Some electronic structure identifiers of the studied adducts are presented in Molecular interactions between the various nitrogen compounds with 2-(1 Table S2. AccordiH-imidazol-2-yl)-4-phenol enhanced adsorption capacities and selectivity for individual nitrogen compounds due to their specific binding nature and high adsorption capacities are described. A better regression R2 presented by Freundlich isotherm confirmed multilayer adsorption attributed to the interactions between imprinted nanofibers and nitrogen compounds, and possibly between nitrogen molecules. The nanofibers displayed excellent adsorption properties when employed under SPE conditions to explore hydrophobic interactions  and hydrophilic interactions . Thermodynamic parameters obtained from isothermal titration calorimetry (ITC) revealed that quinoline–PIMH and pyrimidine–PIMH interactions are exothermic in nature, while carbazole–PIMH is endothermic in nature. Molecular modelling also confirmed that 2-(1H-imidazol-2-yl)-4-phenol indicated that hydrogen bond interactions may take place between the lone-pair nitrogen atom of N-compounds (quinoline and pyrimidine) and the –OH, –NH groups of the PIMH nanofibers. Carbazole on the other hand offers weak interactions. Further DFT also confirmed the feasibility of π–π interactions between the imidazole rings and the aromatic N-compounds. The complex nature of N-compounds in fuel complicate the structure/function approach on MIPs for targeting these unwanted compounds.Molecular imprinting on 2-(1There are no conflicts to declare.RA-008-C8RA00543E-s001


When CuOx/Ag/P25 heterostructure was coupled with the protected metal, the open circuit potential under illumination negatively shifted about 240 mV (vs. Ag/AgCl) and the photoinduced current density reached 16.6 μA cm−2. At the same time, more reactive oxygen species were produced by the Z-shape structure, and then the photocatalytic sterilization effect was stronger. Combined with the chemical sterilization of Ag and the oxide of Cu, the bacterial survival rate of CuOx/Ag/P25 was low (0.006%) compared with the blank sample. This design provides a strategy for developing green dual-functional coating materials with photoelectrochemical anticorrosion and antifouling properties.In the marine environment, steel materials usually encounter serious problems with chemical or electrochemical corrosion and fouling by proteins, bacteria, and other marine organisms. In this work, a green bifunctional Z-scheme CuO Howe~3.2 eV)  and a fale pairs ,18. Tian2− and hydroxyl radicals •OH) under irradiation and their inhibition to the growth of bacteria [3/BiO2−x inactivated bacteria in full spectrum, which is due to a large amount of ROS caused by internal structural defects and the formation of heterostructures. Moreover, the integration of chemical sterilization with photocatalytic sterilization has become a key research goal in the antimicrobial field [2O/Ag composites with strong and long-term antibacterial activities.Regarding the protection against microbial corrosion, the addition of antibacterial components to the protective paints or coatings has been commonly used to achieve antifouling and antibacterial effects . Althougbacteria . Wang etbacteria  reportedal field ,26,27. Yal field  designedx/Ag/TiO2 Z-type heterojunction, which is anticipated as coating material for metal anticorrosion/antifouling in the marine environment on the basis of the following considerations. (i) Both CuOx and TiO2 hold higher conduction-band positions against the potential of stainless steel  and make the transfer of photoinduced electrons to the metal for PECCP possible. (ii) The combination of Ag nanoparticles (NP) with a local surface plasmon resonance (LSPR) effect and small-band-gap CuOx can improve the visible light absorption of TiO2 [x/Ag/TiO2 heterojunction provides an effective charge transfer path for realizing the efficient separation of electron-hole pairs without sacrificing redox ability [x and by active ROS groups produced by photoinduced electrons and holes from the heterojunction [x/Ag/TiO2 not only well demonstrates photocathodic protection performance for 304SS in the simulated seawater but also possesses chemical and photocatalytic synergistic bactericidal activities. Such a green bifunctional coating material shows great promise in metal anticorrosion and antifouling applications in the marine environment.Apparently, both the PECCP performance and photocatalytic antibacterial properties of semiconductors are related to the light absorption, photoinduced charges separation, and the conduction/valence-band positions. In this sense, we herein design a bifunctional CuO of TiO2 ,29. . The diffraction peak intensity at 2θ = 25.3 ° was strong, and the peak shape was symmetrical, indicating that the crystallinity of the material is very good. The reference material CuOx presented characteristic diffraction peaks at 2θ = 36.4 and 42.3 °, corresponding to the (111) and (200) crystal planes of the Cu2O phase of cubic hematite (JCPDS 05-0667). Compared with P25 and CuOx, the diffraction peaks for CuOx/Ag/P25 remained unchanged, indicating that CuOx and Ag did not affect the crystal structure of P25, which may have been due to the small load, the small particle size, and the low crystallinity of CuOx and Ag [x/Ag/P25 were analyzed by TEM and HRTEM. As shown in 2 and the (101) crystal plane of rutile TiO2, respectively. The lattice spacings of 2.1 and 2.4 Å were ascribed to the (100) and (111) crystal planes of Cu2O [x phase and the P25 phase [x/Ag/P25 was mainly composed of irregular particles with a diameter of 20~25 nm. The EDS element distribution mapping in x/Ag/P25. The corresponding element content is listed in XRD measurements were employed to study the crystalline structures of samples. As shown in x and Ag . The mor of Cu2O ,34. The 25 phase . Figure x/P25, Ag/P25, and CuOx/Ag/P25 were further studied by XPS. The Ti 2p spectra for P25 in 1/2 and Ti 2p3/2 of Ti4+, respectively [x/Ag/P25 showed a shift to a higher binding energy, which was possibly due to the strong interaction between CuOx, Ag, and P25 in the heterojunction structure of CuOx/Ag/P25 [2. The slightly shifted peak B, at ~530.9 eV, also belonged to the metal (Ag and Cu) oxide peak, which was attributed to the O atom near the oxygen vacancy [2O molecules on the surface [x/Ag/P25 can be deconvoluted into two peaks, Ag 3d3/2 (373.5 eV) and Ag 3d5/2 (367.5 eV), indicating the existence of Ag metal in the material [x  and the load (CuOx and Ag) made the Cu species stable.The atomic valence states and energy-band structures of CuOectively ,36. Compx/Ag/P25 . The O1s vacancy . Peak C, vacancy , and pea surface . Figure erial [x d, the pel [x  compared with P25 (3.01 eV), CuOx/P25 (2.87 eV) and Ag/P25 (2.49 eV). The photoluminescence (PL) spectra of the catalysts at an excitation wavelength of 550 nm at room temperature were displayed in x/Ag/P25 was lower than that of other compound materials, indicating the lowest recombination rate of e−/h+ pairs. The fluorescence intensity order was CuOx/Ag/P25 < Ag/P25 < CuOx/P25 < P25, which suggested that having Ag NP as the electron bridge promoted the separation and emigration of photogenerated electron-hole pairs [Eg) values of P25 and CuOx were estimated to be 3.01 and 2.05 eV, respectively  spectra in EVB,XPS of P25 and CuOx were 2.55 and 1.5 eV, respectively. The VB positions of P25 and CuOx were calculated as 2.31 eV and 1.26 eV, respectively, by using the following equation: EVB,NHE = φ + EVB,XPS − 4.44, where φ is the work function of the instrument (4.2 eV [UV-visible diffuse reflectance spectra (or UV-vis DRS) were measured to investigate the light absorption of samples. f Ag NPs . Figure le pairs ,45. By pectively c,d. More (4.2 eV ).2− were almost negligible on P25, CuOx/P25, Ag/P25, and CuOx/Ag/P25 in darkness. Both DMPO−•OH and DMPO−•O2− signals with four characteristic peaks with intensity ratios of 1:2:2:1 and 1:1:1:1 [2•− were different in intensity. The intensity order of DMPO−•O2− signals under irradiation was CuOx/Ag/P25 > Ag/P25 > CuOx/P25 > P25; the intensity order of DMPO−•OH signals under irradiation was CuOx/Ag/P25 > Ag/P25 ≈ CuOx/P25 > P25. CuOx/Ag/P25 showed the highest intensity in the characteristic peaks of DMPO−•OH and DMPO−•O2− when compared with those materials.The electron paramagnetic resonance (EPR) spectra of free radical adducts trapped by DMPO in the dark and under irradiation at room temperature for the catalysts are shown in  1:1:1:1 , respectx/Ag/P25 > CuOx/P25 > Ag/P25 > P25. Compared with CuOx/P25 and Ag/P25, CuOx/Ag/P25 displayed a significantly more negative potential shift of 240 mV under illumination, indicating that the introduction of CuOx and Ag improved the separation efficiency of electron-hole pairs, and more electrons were transferred to the coupled 304SS to provide photoelectrochemical cathodic protection. x/P25, Ag/P25, and CuOx/Ag/P25 coupled with 304SS in a 3.65 wt.% NaCl solution with an applied bias potential of 0 V (refE). P25, CuOx/P25, Ag/P25, and CuOx/Ag/P25 showed a positive current density change when the light was turned on, showing the characteristics of an n-type semiconductor [x/P25 and CuOx/Ag/P25 greatly increased at the first light on/off switching. At the same time, using Ag particles as a conducting medium accelerated the separation of electron-hole pairs [x/Ag/P25 had a photocurrent density of 16.6 μA cm2, which was ~1.8 times greater than that of P25, indicating that it had the best PECCP performance. The migration ability of photogenerated carriers could be characterized by electrochemical impedance spectroscopy (EIS).In general, photogenerated cathodic protection works by supplying electrons to the protected metal through an external photosensitive semiconductor, causing the metal potential to be more negative than the original corrosion potential under irradiation. Thus, the photoinduced OCP value is an important parameter to evaluate the PECCP performance of photoanode materials. onductor . It indix/Ag/P25 was larger than that of the other materials, which indicates that the thin film electrode could be used as a coating material to protect 304SS from corrosion [x/Ag/P25 had the smallest arc radius, demonstrating the best carriers transfer efficiency and thus the greatest photochemical cathodic protection effect, which was consistent with the results of OCP response and the photoinduced current. In the corresponding equivalent circuit model, Rs, Rd, and Rc represented the solution resistance, the depletion layer resistance, and the charge transfer resistance [x/Ag/P25 had a higher Rd value than P25, which may have been due to the bending of the Fermi level caused by the formation of a Z-type heterostructure. Moreover, CuOx/Ag/P25 had an Rc value of 1.23 Ω, much smaller than P25 (2.47 × 104), CuOx/P25 (1.22 × 104), and Ag/P25 (300.5), respectively. Therefore, it could be understandable that CuOx/Ag/P25 had the best PECCP performance for 304 SS in a 3.65 wt.% NaCl solution.orrosion . Under iorrosion . Figure sistance , respectE. coli colony–counting method. The optical pictures of E. coli colonies on nutrient agar plates in x/Ag/P25 and Ag/P25 coatings had fewer E. coli colonies than the other samples did, indicating better antibacterial activities under 24 h of illumination. Taking the blank sample without active catalysts as a counterpart in x/P25 in a 1 × 106–times diluted bacterial solution were about 81.1% and 75.4%, respectively. Moreover, as shown in x/Ag/P25 in a 100-times diluted solution were as low as 0.116% and 0.006%, respectively. It is concluded that CuOx/Ag/P25 can effectively inhibit the growth of E. coli.The antibacterial activities of the materials were evaluated by using the CFU method, i.e., an x (−0.79 eV/1.26 eV) and P25 (−0.7 eV/2.31 eV) determined in this work  of CuOx, leaving the photoinduced holes at the VB of P25 for the production of •OH and the photoinduced electrons at the conduction band (CB) of CuOx for the photocathode protection and production of superoxide ions (O2•−). Additionally, the incorporation of Ag NP with the LSPR effect and CuOx with a narrow band gap greatly improved the visible light absorption  production ability upon irradiation and their ability to inhibit the growth of bacteria, viruses, and other micro-organisms provide the antifouling ability of the CuOx/Ag/P25 coating [x and Ag NPs, especially the Cu2O species stabilized by the photoinduced electrons through the unique Z-scheme transfer path  by using the wet chemical reduction method. Typically, 0.5 g of P25 was ultrasonically dispersed in 30 mL of deionized water. Then 5 mL of AgNO3 aqueous solution with a concentration of 1 mg mL−1 was added to the above suspension under vigorous stirring. After fully mixing, an appropriate amount of NaBH4 aqueous solution was added dropwise to reduce Ag+. The molar ratio of NaBH4 to AgNO3 was 4:1. Under continuously stirring for 4 h, the resulting powder was obtained by centrifugation and washing with deionized water and absolute ethanol, separately, several times, followed by drying in an oven at 80 °C to obtain the Ag/P25 sample with a theoretical Ag loading of 1.0 wt.%.First, noble metal Ag was loaded on TiOx was loaded on P25 or Ag/P25 by using the deposition-precipitation method. Next, 0.3 g of P25 or Ag/P25 and 0.0074 g of CuSO4·5H2O were added into 60 mL of 0.2 mol mL−1 NaOH aqueous solution under magnetic stirring for 30 min, followed by the addition of 9.0 mL of 0.1 mol L−1 ascorbic acid aqueous solution, drop by drop. After reaction for 1.5 h, the product was centrifuged and washed with deionized water and absolute ethanol, separately, until the solution was neutral. At last, 1.0 wt.% CuOx/P25 or 1.0 wt.% CuOx/Ag/P25 was obtained after drying the sample overnight in the flowing N2 at 80 °C.Then, CuOx/Ag/P25 (or other sample) was then ultrasonic dispersed in the above 200 μL solvent. The as-obtained ultrasonic slurry was coated on FTO glass substrates with a coating area of 1 cm × 1 cm. Finally, the photoanode coating was obtained after drying in an oven at 40 °C for 3 h.The as-prepared sample was mixed with nafion/ethanol solution under ultrasonic treatment for the preparation of the coating material . Typical−1. The morphologies and element distribution of the samples were observed by high-resolution thermal field emission scanning electron microscope . The crystal interface structures of the samples were analyzed by high-resolution transmission electron microscope  with an accelerating voltage of 300 kV. The element composition and valence state of the catalysts were analyzed by X-ray photoelectron spectroscopy/ESCA . A monochromatic Al Kα X-ray source (hυ = 1486.6 eV) under a vacuum degree of ~2 × 10−9 mbar was used. The surface pollution C1s (284.8 eV) was used as the standard for energy correction. The UV-vis diffuse reflectance spectroscopy (UV-vis DRS) response of catalysts in the wavelength range from 200 to 800 nm was analyzed by integrating a sphere UV-vis spectrophotometer (UV2600) with BaSO4 as a reference. Photoluminescence (PL) spectra were characterized by using Edinburgh FS5 fluorescence spectrometer with an excitation wavelength of 550 nm. Electron paramagnetic resonance (EPR) spectrometer (JES X320) was used to obtain signals of photogenerated radicals spin trapped by 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), e.g., DMPO-•OH and DMPO-O2•−, in the dark and under illumination (190–900 nm) at room temperature. The free radical signals were collected after 12 min.The crystal structures of the prepared powders were analyzed by an X-ray powder diffractometer (Rigaku Ultima IV) equipped with a Cu Kα radiation source. The diffraction patterns in the range of 10 to 80° were recorded at a scan speed of 10° min−2. In a three-electrode system, Pt plate was used as a counter electrode, Ag/AgCl electrode (saturated KCl) was used as a reference electrode, and the photoanode  was used as a working electrode. In the PECCP performance measurements, such as those from the OCP and photocurrent density-time (i-t) tests, the photoanode coupled with 304SS was used as a working electrode. Additionally, a 3.65 wt.% NaCl solution was used as an electrolyte solution to simulate the marine environment. Mott–Schottky (M–S) curves were measured in the potential scope of −1.5 to 0.2 V at a frequency of 1000 Hz. Electrochemical impedance spectroscopy (EIS) was performed in the AC voltage of 10 mV and the frequency range from 105 to 10−2 Hz with or without light illumination.The electrochemical measurements were performed at room temperature using Gamry electrochemical workstation (Gamry Interface1010E). All measurements were carried out after the open circuit potential (OCP) value was stable. A 300 W Xenon lamp (CEL-HXF300) was used as the light source with an optical power density of 200 mW cmEscherichia coli (E. coli) in a beef-extract-peptone (BEP) medium at 37 °C for 24 h. The concentration of the bacterial suspension was adjusted to 3 × 107~3 × 108 CFU mL−1. The catalysts were dispersed by deionized water to a concentration of 2 mg mL−1. The mixture of 1 mL of catalyst, 1 mL of BEF, and 100 μL of E. coli suspensions was cultured on a shaking table  under simulated solar irradiation at 37 °C for 24 h (16000LX). At the end of the incubation period, the culture medium was sampled to determine the viable counts of planktonic bacteria. The viable bacteria in the sampled suspension were counted by using a 10-times gradient dilution method. Specifically, 100 μL of a diluted sample was transferred to an LB agar plate, which was cultured in a bacterial incubator (MJX-150) at 37 °C for 24 h. Finally, the colonies were counted, and the antibacterial activities of the catalysts were compared according to the bacterial survival rate α, as calculated byThe antibacterial activities of the materials were evaluated by using the CFU method (a plate-counting method) using x/Ag/P25 coatings on FTO glass substrates, which displayed excellent photocathodic protection performance and antifouling activities under simulated solar illumination in a 3.65 wt.% NaCl solution. The photoelectrochemical measurements and characterizations revealed that a Z-type CuOx/Ag/P25 heterostructure provided a photogenerated carrier transfer channel, which facilitated carrier separation and resulted in a more negative OCP shift of 240 mV. Meanwhile, the Z-type heterojunction of coatings had high-conduction-band and deep-valance-band potentials, which generated more reactive oxygen species of •O2− and •OH radicals, thus effectively killing E. coli bacteria, with a low survival rate of 0.006%.In summary, we have successfully prepared CuO