Electrochemical studies and differential pulse polarographic analysis of lansoprazole in pharmaceuticals

Abstract

The electrochemical reduction of lansoprazole was investigated by cyclic voltammetry and direct current and differential pulse polarography. The reduction potential was -1.32 V vs. Ag/AgCl with a dropping mercury electrode in a supporting electrolyte consisting of phosphate buffer (pH 9.0)-tetramethylammonium iodide (4 + 1). The reversibility of the electrode reaction and the type of limiting current were studied. The temperature coefficient and the diffusion constant were determined. A mechanism for the electrode reaction was proposed. A new simple and sensitive differential pulse polarographic method was also developed for the quantification of lansoprazole. A linear calibration graph was obtained in the range 0.04-11.35 micrograms ml-1. The limit of detection was 0.03 microgram ml-1 and the intra- and inter-day precisions were 0.84-2.32 and 0.72-3.09%, respectively. The developed method was applied to six different commercial pharmaceutical capsule preparations containing enteric-coated granules. The relative standard deviations ranged from 1.36 to 2.85%. Recovery studies for the accuracy of the method were performed by adding a synthetic mixture to known amounts of lansoprazole and the mean recovery was 100.45%. The data obtained from commercial preparations were compared with those from a published spectrophotometric method. No difference was found statistically.

Electrochemical study of fluvastatin sodium – analytical application to pharmaceutical dosage forms, human serum, and simulated gastric juice

“…Modern computer-based electrochemical instrumentation has increased the usefulness of electrochemical methods in pharmaceutical analysis and several electrochemical methods have been developed for the determination of drugs in pharmaceutical dosage forms and biological fluids [7,8,9,10,11,12,13,14,15]. The advance in experimental electrochemical techniques in the field of drug analysis is because of their simplicity, low cost, and relatively short analysis times when compared with other techniques.…”

Sensitive amperometric detection of omeprazole and pantoperazole at electrodeposited nickel oxide nanoparticles modified glassy carbon electrode

“…As a result, they have been used for determination of a wide range of pharmaceutical formulations. The reduction process and quantitative determination of omeprazole and lansoprazole have been investigated by several polarographic techniques [26][27][28][29]. Differential pulse voltammetry and cyclic voltammetry at mercury, carbon paste, and glassy carbon electrodes were used for the determination of lansoprazole, pantoprazole, and omeprazole in pharmaceutical formulations [30][31][32][33].…”

Rapid determination of telmisartan in pharmaceuticals and serum by the parallel catalytic hydrogen wave method

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