The use of ultra-violet setting glue for microelectrode fabrication
Abstract The characteristics of glues which set in ultra-violet light are described with respect to their advantages for microelectrode assembly.
A simple and comprehensive method for the construction, repair and recycling of single and double tungsten microelectrodes
A method for the construction, repair and recycling of tungsten-in-glass micro-electrodes is described. Essentially, the method employs insulating tungsten electrodes by collapsing borosilicate-glass capillaries onto tungsten wires. Procedures are described for either (1) removing excess glass insulation from the microelectrode tip or (2) fine adjustment and reshaping of the exposed electrode tip. This approach enables the controlled shaping of the electrode tip during preparation and/or reshaping the electrode tip or glass insulation of damaged electrodes. The method may be applied in the preparation of bipolar tungsten-in-glass electrode and tungsten electrode/micropipette assemblies. Advantages of the method are discussed.
Recent progress in engineering near-infrared persistent luminescence nanoprobes for time-resolved biosensing/bioimaging
Persistent luminescence nanoprobes (PLNPs) can remain luminescent after ceasing excitation. Due to the ultra-long decay time of persistent luminescence (PersL), autofluorescence interference can be efficiently eliminated by collecting PersL signal after autofluorescence decays completely, thus the imaging contrast and sensing sensitivity can be significantly improved. Since near-infrared (NIR) light shows reduced scattering and absorption coefficient in penetrating biological organs or tissues, near-infrared persistent luminescence nanoprobes (NIR PLNPs) possess deep tissue penetration and offer a bright prospect in the areas of in vivo biosensing/bioimaging. In this review, we firstly summarize the design of different types of NIR PLNPs for biosensing/bioimaging, such as transition metal ions-doped NIR PLNPs, lanthanide ions-doped NIR PLNPs, organic molecules-based NIR PLNPs, and semiconducting polymer self-assembled NIR PLNPs. Notably, organic molecules-based NIR PLNPs and semiconductor self-assembled NIR PLNPs, for the first time, were introduced to the review of PLNPs. Secondly, the effects of different types of charge carriers on NIR PersL and luminescence decay of NIR PLNPs are significantly emphasized so as to build up an in-depth understanding of their luminescence mechanism. It includes the regulation of valence band and conduction band of different host materials, alteration of defect types, depth and concentration changes caused by ion doping, effective radiation transitions and energy transfer generated by different luminescence centers. Given the design and potential of NIR PLNPs as long-lived luminescent materials, the current challenges and future perspective in this rapidly growing field are also discussed.