%0 Journal Article
%T Fluorescence Spectrometric Determination of Drugs Containing -Methylene Sulfone/Sulfonamide Functional Groups Using N1-Methylnicotinamide Chloride as a Fluorogenic Agent
%A Khaled M. Elokely
%A Mohamed A. Eldawy
%A Mohamed A. Elkersh
%A Tarek F. El-Moselhy
%J International Journal of Analytical Chemistry
%D 2011
%I Hindawi Publishing Corporation
%R 10.1155/2011/840178
%X A simple spectrofluorometric method has been developed, adapted, and validated for the quantitative estimation of drugs containing -methylene sulfone/sulfonamide functional groups using N1-methylnicotinamide chloride (NMNCl) as fluorogenic agent. The proposed method has been applied successfully to the determination of methyl sulfonyl methane (MSM) (1), tinidazole (2), rofecoxib (3), and nimesulide (4) in pure forms, laboratory-prepared mixtures, pharmaceutical dosage forms, spiked human plasma samples, and in volunteer's blood. The method showed linearity over concentration ranging from 1 to 150£¿ g/mL, 10 to 1000£¿ng/mL, 1 to 1800£¿ng/mL, and 30 to 2100£¿ng/mL for standard solutions of 1, 2, 3, and 4, respectively, and over concentration ranging from 5 to 150£¿ g/mL, 10 to 1000£¿ng/mL, 10 to 1700£¿ng/mL, and 30 to 2350£¿ng/mL in spiked human plasma samples of 1, 2, 3, and 4, respectively. The method showed good accuracy, specificity, and precision in both laboratory-prepared mixtures and in spiked human plasma samples. The proposed method is simple, does not need sophisticated instruments, and is suitable for quality control application, bioavailability, and bioequivalency studies. Besides, its detection limits are comparable to other sophisticated chromatographic methods. 1. Introduction Encouraged by the successful application of the NMNCl methodology to the determination of a similar ¦Á-methylene carbonyl functional group containing drugs, namely, warfarin [1], pentoxifylline, propafenone hydrochloride and acebutolol hydrochloride [2], the almost isosteric ¦Á-methylene sulfoxide group, such as proton pump inhibitors (PPIs) and the cyclic ¦Á-methylene carbonyl group, such as ketamine hydrochloride, griseofulvin, and levonorgestrel (unpublished results), we decided to investigate the possibility of extending the application of such methodology to drugs containing the isosteric ¦Á-methylene sulfone/sulfonamide functional groups, namely, methyl sulfonyl methane (MSM) (1), tinidazole (2), rofecoxib (3), and nimesulide (4). Methyl sulfonyl methane (MSM) (1) is a relatively new dietary supplement form of sulfur that is found in our living tissues. MSM supports healthy connective tissues like tendons, ligaments, and muscle. Thus, it is important in conditions such as arthritis, muscle pains, and bursitis. MSM should be considered an integral part of any health care practice because of its physiological action, indirect importance, and current/future uses [3¨C5]. In this report, MSM was used as a model compound and was found to react successfully with NMNCl
%U http://www.hindawi.com/journals/ijac/2011/840178/