Spectrofluorimetric Investigation For Determination of Sumatriptan Succinate: Application to Tablets and Spiked Human Plasma

Abstract A highly sensitive spectrofluorometric method was developed for the determination of verapamil hydrochloride (VP HCl) in pharmaceutical formulations and biological fluids. The proposed method is based on investigation of the fluorescence spectral behavior of VP HCl in micellar systems, such as sodium dodecyl sulfate (SDS) and β-cyclodextrin (β-CD). In aqueous solutions of borate buffer of pH 9 and 8.5, VP HCl was well incorporated into SDS and β-CD, respectively, with enhancement of its native fluorescence. The fluorescence was measured at 318 nm after excitation at 231 nm. The fluorescence intensity enhancements were 183 and 107% in SDS and in β-CD, respectively. The fluorescence-concentration plots were rectilinear over the range of 0.020.2 and 0.020.25 μg/mL, with lower detection limits of 5.58 × 103 and 3.62 × 103 μg/mL in SDS and β-CD, respectively. The method was successfully applied to the analysis of commercial tablets and the results were in good agreement with those obtained with the official method. The method was further applied to the determination of VP HCl in real and spiked human plasma. The mean % recoveries in the case of spiked human plasma (n 4) was 92.59 3.11 and 88.35 2.55 using SDS and β-CD, respectively, while that in real human plasma (n 3) was 90.17 6.93 and 89.17 6.50 using SDS and β-CD, respectively. The application of the method was extended to the stability studies of VP HCl after exposureto ultraviolet radiation and upon oxidation with hydrogen peroxide.

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Spectrofluorimetric Determination of Warfarin Sodium by Using N1-Methylnicotinamide Chloride as a Fluorigenic Agent

Journal of AOAC International ◽

10.1093/jaoac/88.2.455 ◽

2005 ◽

Vol 88 (2) ◽

pp. 455-461 ◽

Cited By ~ 4

Author(s):

Mohamed A El Dawy ◽

Mokhtar M Mabrouk ◽

Riad A El Barbary

Keyword(s):

Aqueous Solutions ◽

Human Plasma ◽

Plasma Samples ◽

Spiked Human Plasma ◽

Human Plasma Samples ◽

Warfarin Sodium ◽

Spectrofluorimetric Method ◽

Spectrofluorimetric Determination ◽

Methylene Groups

Abstract A spectrofluorimetric method is described for the determination of drugs containing active methylene groups adjacent to carbonyl groups. The method was applied successfully to the determination of warfarin sodium in laboratory-prepared mixtures, in commercial tablets, and in spiked human plasma samples. Finally, the method was applied to the determination of the steady-state concentration of warfarin sodium in the blood of a hospitalized patient. The method involves the reaction of warfarin sodium with 0.2 ml (0.4 × 10−3M) N1-methylnicotinamide chloride reagent in the presence of 3 mL 1.0N NaOH and cooling in ice for 8 min, followed by adjustment of the pH to 2.0, using formic acid and heating for 4 min, whereby a highly fluorescent reaction product is produced. The optimal wavelengths of excitation and emission were determined by using a synchronous wavelength search and found to be 284 and 354 nm, respectively. The standard curves were linear over a concentration range of 50–1500 ng/mL in both aqueous solutions and spiked human plasma samples. The mean recoveries (± standard deviation) were 101.157 (±1.33) and 95.73 (±1.88%) for aqueous solutions and spiked human plasma samples, respectively. The method showed good specificity and precision. The proposed method is simple and economical because of its minimal instrumentation and chemicals requirements. Nevertheless, it is highly sensitive, specific, and reproducible. Accordingly, it is suitable for quality-control applications, drug monitoring, and bioavailability and bioequivalency studies.

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