Determination of diltiazem hydrochloride enantiomers in dog plasma using chiral stationary-phase liquid chromatography.

Analytical Chemistry Research Laboratory, Tanabe Seiyaku Co., Ltd., Osaka, Japan.
Journal of Chromatography A (Impact Factor: 4.26). 04/1991; 564(1):338-45. DOI: 10.1016/0378-4347(91)80100-Q
Source: PubMed

ABSTRACT The separation and determination of d- and l-diltiazem hydrochloride in dog plasma by a two-column high-performance liquid chromatographic technique are described. Diltiazem hydrochloride and its metabolites were extracted from dog plasma and analyzed on a conventional column (Nucleosil 5C18) with a volatile buffer system. The column effluent of diltiazem hydrochloride was collected and evaporated. The enantiomeric ratio of the collected diltiazem was determined using a chiral column (Chiralcel OC). The method was accurate and sensitive.

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