Original scientific paper

https://doi.org/10.2478/acph-2021-0038

Determination of penicillamine, tiopronin and glutathione in pharmaceutical formulations by kinetic spectrophotometry

LEA KUKOC-MODUN ; Department of Analytical Chemistry, Faculty of Chemistry and Technology, University of Split, 21000 Split, Croatia
MAJA BIOCIC ; Department of Analytical Chemistry, Faculty of Chemistry and Technology, University of Split, 21000 Split, Croatia
NJEGOMIR RADIĆ ; Department of Analytical Chemistry, Faculty of Chemistry and Technology, University of Split, 21000 Split, Croatia

Abstract

A novel and simple method for the determination of penicillamine (PEN), tiopronin (mercaptopropionyl glycine, MPG) and glutathione (GSH) in pharmaceutical formulations by kinetic spectrophotometry has been developed and validated. It is based on the redox reaction where the thiol compound (RSH) reduces CuII-neocuproine complex to CuI-neocuproine complex. The non-steady state signal of the formed CuI- neocuproine complex is measured at 458 nm. The initial rate and fixed time (at 1 min) methods were validated. The calibration graph was linear in the concentration range from 8.0 × 10‒7 to 8.0 × 10‒5 mol L–1 for the initial rate method and from 6.0 × 10‒7 to 6.0 × 10‒5 mol L–1 for the fixed time method, with the detection limits of 2.4 × 10‒7 and 1.4 × 10‒7 mol L–1, resp. Levels of PEN, MPG and GSH in pharmaceutical formulations were successfully assayed by both methods. The advantages of the presented methods include sensitivity, short analysis time, ease of application and low cost.

Keywords

penicillamine; tiopronin; glutathione; kinetic spectrophotometry; pharmaceutical formulations

Hrčak ID:

245671

URI

https://hrcak.srce.hr/245671

Publication date:

31.12.2021.

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