DC polarographic and spectrophotometric determination of ampicillin capsules
Squella, J.A.; Nunez-Vergara, L.J.; Aros, M.
Journal - Association of Official Analytical Chemists 63(5): 1049-1051
1980
ISSN/ISBN: 0004-5756 PMID: 7410296 Document Number: 155977
Polarographic and spectrophotometric methods are proposed for the determination of ampicillin in capsules. Acidic hydrolysis of ampicillin with 1% HCHO in 0.3N HCl yields a degradation product identified as 2-hydroxy-3-phenyl-6-methylpyrazine. This compound has a well defined UV absorption band at 380 nm and a polarographic wave at –0.55 V vs SCE, which can be used for analytical purposes. Individual capsule assays, composite assays, and recovery studies are described. The average recovery values and standard deviations (SD) for UV and polarographic determinations were 99.20% (SD 0.95) and 100.85% (SD 1.09), respectively