Abstract

ROLE OF ALKALOIDAL PRECIPITANTS FOR THE ASSAY OF QUINAPRIL HYDROCHLORIDE IN BULK AND PHARMACEUTICAL FORMULATIONS BY SPECTPOSCOPY

*K.Harinadha Baba, Dr C.Ram Babu, Dr J.V.Ln.Seshagiri Rao and K.Anilkumar

Abstract

Simple spectrophotometric methods (A-C) for the assay of Quinapril (QUI) based on the formation of its complexes with alkaloidal precipitants are described. QUI under go quantitative precipitation in the form of molecular complexes with iodine (I2, method A), ammonium molybdate (AM, method B) or phosphomolybdic acid (PMA, method C) when used in excess. In addition to precipitation reactions, color reactions have also been combined to estimate QUI. They are based on the color formation with either unreacted precipitant of the filtrate (I2) or released precipitant from the molecular complex (AM or PMA) with chromogenic reagent such as P-N-methyl amino phenol sulphate (PMAP)-sulphanilic acid (SAc) (for I2), potassium thiocyanate (for AM), cobalt nitrate (Co(II))-disodium salt of ethylene diamine tetra acetic acid (EDTA) complex (for PMA).

Keywords: Alkaloidal, Molybdate, Phosphomolybdic, Sulphate, Thiocyanate.