Premium
Analysis of Drugs by Polarography, XXXV: The Polarographic Behaviour of Cinolazepam. [1‐(2‐Cyanoethyl)‐7‐chloro‐3‐hydroxy‐5‐(2‐fluorophenyl)‐1,3‐dihydro‐2 H ‐1,4‐benzodiazepin‐2‐one] and Assay of its Tablets
Author(s) -
Oelschläger H.,
Volke J.,
Belal F.
Publication year - 1992
Publication title -
archiv der pharmazie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.468
H-Index - 61
eISSN - 1521-4184
pISSN - 0365-6233
DOI - 10.1002/ardp.19923250202
Subject(s) - polarography , dropping mercury electrode , chemistry , electrode , adsorption , diffusion , electrochemistry , cathodic protection , high performance liquid chromatography , chromatography , inorganic chemistry , organic chemistry , thermodynamics , physics
Cinolazepam is reduced at the Dropping Mercury Electrode (DME) over the entire pH range in Britton Robinson buffers (BRB) containing 20% DMF as a solubilizer. A well‐defined cathodic wave is obtained over the pH range 3‐5, which is very suitable for analytical purposes. The wave was characterized as being irreversible, diffusion‐controlled and free from adsorption phenomena. In acid buffers, 4 electrons are consumed in the reduction process, while in alkaline buffers the electrode reaction is somewhat complicated. Tablets containing 40 mg cinolazepam were analysed using the polarographic and a developed HPLC method. The results obtained with both methods are in good accordance as revealed by statistical analysis. The details of the complicated mechanism of the reduction process at the DME are still under investigation but elucidated in principle.