Simultaneous Determination of Clidinium Bromide and Chlordiazepoxide in Combined Dosage Forms by High-Performance Liquid Chromatography
A sensitive and precise RP-HPLC method has been developed for the simultaneous estimation of clidinium bromide (CDB) and chlordiazepoxide (CDZ) in pure and pharmaceutical formulations. The separation was achieved on a Nucleodur C8 (250 × 4.6 mm i.d., 5 μm particle size) column at 25°C. CH3CN-MeOH-NH4OAc 0.1M (30 : 40 : 30, v/v/v) was used as the mobile phase at a flow rate of 1.0 mL min−1 and detector wavelength at 218 nm. Almotriptan (ALT) was used as internal standard. The validation of the proposed method was carried out for linearity, accuracy, precision, LOD, LOQ, and robustness. The method showed good linearity in the ranges of 2.5–300.0 and 3.0–500.0 μg mL−1 for CDB and CDZ, respectively. The percentage recovery obtained for CDB and CDZ was 100.40–103.38 and 99.98–105.59%, respectively. LOD and LOQ were 0.088 and 0.294 μg mL−1 for CDB and 0.121 and 0.403 μg mL−1 for CDZ, respectively. The proposed method was successfully applied to the determination of CDB and CDZ in combined dosage forms and the results tallied well with the label claim.
Evaluation of the Efficiency of Smart Stability-Indicating Spectrophotometric Methods Based on Mathematical and Statistical Processing of the Obtained Results Via Different Manipulating Pathways


 Smart different stability-indicating spectrophotometric methods have been
established for the assay of chlordiazepoxide and clidinium bromide without the intervention of alkaline
degradate of clidinium via various and different manipulating pathways without previous separation
steps.



The specificity of the established methods was inspected by analysing mixtures of cited
drugs in the existence of the alkali-induced degradation product.



These methods were employed either on scanned zero-order absorption spectra using absorbance
subtraction, dual wavelength and Q-absorbance ratio or the amplitudes of the ratio spectra of
zero-order absorption spectra like amplitude modulation and by derivative techniques to the ratio spectra
as a derivative ratio method. In addition, the absorbance of the recovered zero-order absorption spectra
was applied by successive ratio subtraction coupled with constant multiplication. Finally, the pathway
depends on the amplitudes of the derivative spectra, successive derivative subtraction coupled with
constant multiplication. The ranges of linearity were (1-12µg/mL) for chlordiazepoxide and (3-
12µg/mL) for clidinium bromide.



The outcomes achieved by the prospective methods were in consent with those of the official
and reported methods when statistically compared using student’s t test, F-test and one-way ANOVA
where no significant difference was detected with suitable precision, proving the absence of any important
difference in accuracy and precision between them. They were confirmed in accordance with International
Conference on Harmonization guidelines.



The established methods can be considered as alternative methods for the routine determination
of this fixed dose combination with minimum sample preparation.

Construction and analytical applications of plastic membrane electrode for oxymetazoline hydrochloride.
A new oxymetazoline (OM) ion-selective PVC membrane electrode based on the ion associate of OM with phosphotungstic acid was prepared. The electrode exhibits a linear response with a mean calibration graph slope of 57.16 mV decade(-1) at 25 degrees C within the concentration range of 1.96 x 10(-5) - 1 x 10(-2) M OMCl. The change in the pH within the range of 1.0 - 9.4 did not affect the electrode performance. The standard electrode potentials were determined at different temperatures and used to calculate the isothermal coefficient of the electrode (-0.001233 V). The electrode showed a very good selectivity for OM with respect to a large number of inorganic cations and compounds. The standard addition method and potentiometric titration were applied to the determination of (OM) with RSD not exceeding 1.19%.