Electroanalytical Determinations of Halazepam: Study of Interaction with Human Serum Albumin

✍ Scribed by A. Zapardiel; E. Bermejo; J.A.P. Lopez; L. Hernandez; E. Gil

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 557 KB
• Volume: 52
• Category: Article
• ISSN: 0026-265X
• DOI: 10.1006/mchj.1995.1065

✦ Synopsis

The electrochemical behavior of the benzodiazepine halazepam was investigated by differential pulse and tast polarography in water/methanol solutions. Reduction of halazepam was performed in one irreversible, diffusion-controlled step using Britton-Robinson buffers. The peak potential at (\mathrm{pH} 8.5) and a (10 %) methanol/water solution was (-1.10 \mathrm{~V}(\mathrm{vs} \mathrm{Ag} / \mathrm{AgCl}) (3 M \mathrm{KCl})). Halazepam can be determined at nanomolar levels, using adsorptive stripping voltammetry. Applicability of tests on commercial preparations and human urine are described. The detection limit was (25 \mathrm{ng} \mathrm{ml}^{-1}) of urine for an accumulation time of (20 \mathrm{~s}); the mean standard deviation was lower than (3.0 %) for (264 \mathrm{ng} \mathrm{ml}^{-1}) samples ((n=3)) with a mean recovery of (97 %). A study of the interaction of human serum albumin with halazepam and diazepam has been performed by differential pulse polarography; a lower affinity of halazepam for HSA was established. o 1995 Academic Press, Inc.