MICELLAR ENHANCED SYNCHRONOUS FLUORESCENCE FOR THE ASSAY OF SUMATRIPTAN SUCCINATE IN PHARMACEUTICAL TABLETS

Objective: To develop a sensitive, fast and selective method for the determination of sumatriptan succinate (SUM) in pharmaceutical samples. Methods: The method is based on measuring the synchronous fluorescence of SUM using ∆λ of (120 nm) and at a wavelength of excitation and emission of 230 and 325 nm respectively, using Agilent Technology, Cary eclipse, G9800AA model Luminescence spectrometer. Effect of variables on fluorescence emission intensities was studied such as solvent, surfactant, and pH. The proposed method was validated in term of linearity, limit of detection as per the international conference on harmonization guidelines ICH Q2 (R1). Results: The linearity of the method was obtained with a wide range of (50-150) ng/ml with a high value of correlation coefficient value of (0.992). Limits of detection (LOD) and limits of quantitation (LOQ) were found to be 16.3 and 49.5 ng/ml respectively, the mean recovery was found to be 99.1% with low relative standard deviation (% RSD). The method was also compared statistically with the reference method using t-test and f-test, the results show no difference either in pure or pharmaceutical tablets. Conclusion: The obtained results revealed that the developed method can be applied successfully for the determination of SUM in drug formulations samples with good accuracy and precision

Development and validation of spectrophotometric and spectrofluorimetric methods for determination of cilnidipine

Purpose: To develop simple and reliable quantitative methods for the determination of cilnidipine (CLD) in pharmaceutical tablets.Methods: Two simple and sensitive methods (spectrophotometric and spectrofluorimetric) were developed for the determination of cilnidipine (CLD) in pure form and in a pharmaceutical preparation. Spectrophotometric method (A) is based on oxidation of CLD with a known excess amount of Nbromosuccinamide (NBS) in acidic medium, followed by addition of methyl orange indicator and absorbance measurement at 510 nm. The spectrofluorimetric method (B) is based on oxidation of CLD to cerium (IV), followed by measurement of fluorescence emission of Ce (III) at 350 nm. Factors that affect the performance of the two methods were studied and optimized.Results: The spectrophotometric and spectrofluorimetric procedures were successfully used for measuring CLD levels in pharmaceutical dosage form, in the ranges of 2.0 - 25.0 and 0.25 - 11.2 μg/mL, at detection limits of 1.05 and 0.13 μg/mL, respectively. There were no significant differences between the proposed methods and a standard reference method (p < 0.05).Conclusion: The developed methods provide simple and reliable procedures for quantitative measurement of CLD in bulk and tablet forms. Keywords: Cilnidipine, Oxidation, Spectrophotometric, Spectrofluorimetric, Drug formulatio

A sequential injection system for spectrophotometric determination of ketoconazole

Sequential injection analysis (SIA) with spectrophotometric detection is used for a fast determination of ketoconazole in pure and pharmaceutical preparations. The developed method is based on oxidation of ketoconazole with cerium ion in an acidic medium, which leads to the formation of a coloured product that absorbs at a wavelength of 496 nm. Then automation of the method is developed using the SIA technique. All variables that affect the reaction response are studied and optimised using univariate and simplex optimisation. The method is applicable for the determination of ketoconazole in the range of 20-120 µg mL-1