Fluorometric determination of drugs containing cyclic -methylene carbonyl groups using N1- methylnicotinamide chloride as a fluorogenic agentAuthor(s): Khaled M.Elokely, Mohamed A.Eldawy, Mohamed A.Elkersh, Tarek F.El-Moselhy
A simple fluorometric method has been developed and validated for the quantitative estimation of drugs containing cyclic -methylene carbonyl functional groups using N1-methylnicotinamide chloride (NMNCl) as a fluorogenic agent. The proposed method has been applied successfully to the determination of ketamine (1), griseofulvin (2) and levonorgestrel (3) in pure form, in laboratoryprepared mixtures, in pharmaceutical dosage forms and in spiked human plasma samples and volunteers blood. For standard and assay solutions, the method showed linearity over concentration ranging from 50-2300 ng/ml for (1) at pH 3.5, 1-100 ng/ml for (2) at pH 4.1, and 0.5-0.6 ng/ml and 0.01-0.9 ng/ ml for (3) at pH 3.5 and 11.5, respectively. For spiked human plasma samples, the method showed linearity over concentration ranging from 50-2200 ng/ml for (1) at pH 3.5, 1-100 ng/ml for (2) at pH 4.1, and 0.5-0.6 ng/ml and 0.01-0.9 ng/ml for (3) at pH 3.5 and 11.5, respectively. The proposed method is simple, does not need sophisticated instruments, suitable for quality control application, bioavailability and bioequivalency studies. Besides, its detection limits are comparable to other sophisticated chromatographic methods.