Packed-column supercritical fluid chromatography for the purity analysis of clevidipine, a new dihydropyridine drug

• Published in: Journal of Chromatography A Vol. 862; no. 1; pp. 95 - 104
• Main Authors: Gyllenhaal, Olle, Karlsson, Anders, Vessman, Jörgen
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05-11-1999; Elsevier
• Subjects: Analysis; Antihypertensive Agents - analysis; Antihypertensive Agents - isolation & purification; Biological and medical sciences; Chromatography, Liquid - methods; Clevidipine; General pharmacology; Medical sciences; Pharmacology. Drug treatments; Pyridines - analysis; Pyridines - isolation & purification; Sensitivity and Specificity; Silicon Dioxide; Clevidipine; Purity analysis; Chemical analysis; Ultraviolet detector; Phase composition; Impurity; Quality control; Purity control; Dihydropyridine derivatives; Mobile phase; Optimization; Supercritical fluid chromatography
• ISSN: 0021-9673
• DOI: 10.1016/S0021-9673(99)00921-8

In this paper we describe a packed column supercritical fluid chromatography method that can be used for the analysis of a new dihydropyridine substance. The method is based on methanol-modified carbon dioxide as the mobile phase and Hypersil bare silica as column support at a column temperature of 50°C and 150 bar as back pressure. Using an adjusted methanol gradient the most likely by-products can be separated and detected (240 nm) within 13 min. Occasionally the column needed treatment with 4 m
M citric acid in the methanol modifier in order to give a narrow peak of an acidic analogue. The present method can detect analogues at the 0.1% (w/w) level. The precision at this level for one of the analogues was 5.9% RSD. This method shows a higher selectivity than a corresponding reversed-phase liquid chromatographic method.