الفهرس 
Precolumn fluorescence labelling of sodium valproate using 9-chloromethylanthraceneOnly 14 pages are availabe for public view
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Abstract
This thesis presents new analytical methods for determination of some selected carboxylic group containing compounds in pharmaceutical dosage forms or spiked human plasma after deivatization with suitable labelling reagents. The compounds selected for this study are: Sodium valproate (Na- VLP), Azelaic acid (AZA), phenylpyruvic acid (PPA) and Pregabalin (PRG). It consists of five parts: Part I This part describes a general introduction about carboxylic group containing compounds and different reagents that have been reported for derivatization of such compounds Part II This part deals with the development of RP-HPLC method with fluorescence detection for determination of sodium valproate in bulk, tablet dosage form and spiked human plasma. The method is based on the reaction between 9-chloromethyl anthracene and carboxylic moiety of sodium valproate in presence of tetrabutylammonium bromide catalyst to give highly fluorescent derivative. Optimum reaction conditions: 350 μL of 9-chloromethylanthracene reagent (0.2 mg/mL), 300 μL of tetrabutylammonium bromide catalyst (1 mg/mL), 15 μL of benzoic acid solution (25 μg/mL),100 μL of sodium valproate working solution and heating the reaction mixture in water bath at 78°C±0.2 for 40 min in the dark. chromatographic analysis was performed on Inertsil® ODS.3 (250 mm x 4.6 mm, particle size: 5μm) reversed phase column .The mobile phase consisting of ethanol and water in a ratio of 85:15 (v/v) was used at a flow rate of 1.0 mL/min. The fluorescence detector was programmed at excitation and emission wavelengths 365 nm and 413 nm respectively. The injection volume was 20 μL. The proposed HPLC method was linear over the concentration range of 0.25-20 μg/ml with limit of quantitation and limit of detection of 66.81 ng/ml and 22.047 ng/ml respectively and was successfully applied for determination of sodium valproate in tablet dosage form with no interference from excipients, the mean % recovery was found to be 100.898% ± 0.556. Furthermore, the method was also successfully applied for determination of sodium valproate in spiked human plasma without any interference from plasma matrix with mean % recovery of 100.402% ± 0.844. The linearity range of Na-VLP in spiked human plasma was found to be 2-16 μg/ml with limit of quantitation and limit of detection of 142.01 ng/ml and 46.863 ng/ml respectively. Part III This part deals with the development of spectrofluorimetric method for determination of azelaic acid in bulk and cream dosage form The method is based on the reaction between 9-chloromethyl anthracene and dicarboxylic moiety of azelaic acid in presence of tetrabutylammonium bromide catalyst and triethylamine base to give highly fluorescent derivative. Optimum reaction conditions: 250 μL of 9-chloromethylanthracene reagent (0.2 mg/mL), 250 μL of tetrabutylammonium bromide catalyst (10 mg/mL), 50 μL of triethylamine solution ( 1% v/v), 100 μL of azelaic acid working solution and heating the reaction mixture in water bath at 75°C±0.2 for 30 min in the dark. The proposed method was linear over the concentration range of 0.5-15 μg/ml with limit of detection and limit of quantitation of 0.143 μg/ml and 0.434 μg/ml respectively and was successfully applied for determination of azeliac acid in cream dosage form with no interference from excipients, the mean % recovery was found to be 100.547% ± 0.775. Part IV This part deals with the development of spectrofluorimetric method for determination of phenylpyruvic acid in bulk and spiked human plasma The method is based on the reaction between 9-chloromethyl anthracene and carboxylic moiety of phenylpyruvic acid in presence of tetrabutylammonium bromide catalyst and triethanolamine base to give highly fluorescent derivative. Optimum reaction conditions: 300 μL of 9-chloromethylanthracene reagent (0.2 mg/mL), 200 μL of tetrabutylammonium bromide catalyst (10 mg/mL), 40 μL of triethanolamine solution ( 1% v/v), 100 μL of phenylpyruvic acid working solution and heating the reaction mixture in water bath at 75°C±0.2 for 25 min in the dark. The proposed method was linear over the concentration range of 0.05-2 μg/ml with limit of detection and limit of quantitation of 12.473 ng/ml and 37.798 ng/ml respectively and was successfully applied for determination of phenylpyruvic acid in spiked human plasma with no interference from plasma matrix, the mean % recovery was found to be 100.759% ± 0.507. The linearity range of PPA in spiked human plasma was found to be 0.1-1.6 μg/ml with limit of detection and limit of quantitation of 16.338 ng/ml and 49.508 ng/ml respectively Part V This part deals with the development of spectrofluorimetric method for determination of pregabalin in bulk and capsule dosage form. The method is based on the reaction between 1-pyrenyldiazomethane and carboxylic moiety of pregabalin to give highly fluorescent derivative. Optimum reaction conditions: 200 μL of 1-pyrenyldiazomethane (0.4 mg/mL), 100 μL of pregabalin working solution and keeping the reaction mixture at room temperature for 45 min. The proposed spectrofluorimetric method was linear over the concentration range of 40-500 ng/ml with limit of detection and limit of quantitation of 9.190 ng/ml and 27.850 ng/ml respectively and was successfully applied for determination of pregabalin in capsule dosage form with no interference from excipients, the mean % recovery was found to be 100.551% ± 1.063. For all previously mentioned methods described in the previous parts, the statistical analysis of the results including the derivation of the regression equations for the different calibration curves, accuracy, precision, limits of detection and quantitation and specificity have been carried out.