Chiral Separation of Some Cardiovascular Drugs in Biological Fluids Using Capillary Electrophoresis

Abstract

Currently, there is a remarkable interest in the separation and quantification of enantiomeric compounds because of their importance in biochemistry, therapeutic drug monitoring (TDM), pharmaceutical, forensic, etc. The concentration of drugs in biological samples is in trace levels, therefore developing the simple and reliable analytical methods for determination of trace levels of pharmaceuticals in biological fluids gain much attention. Capillary electrophoresis (CE) is an interesting technique that shows high resolution for the enantiomers. This is carried out by adding suitable chiral selector to the background electrolyte results to enantioseparation. According to WHO organization report, cardiovascular diseases (CVDs) rank the leading cause of death, globally. β-blockers such as carvedilol and calcium-channel blockers such as verapamil have chiral center and offer as first-line treatment in the management of CVDs. In this work, CE methods have been developed for the separation and quantification of the enantiomers of carvedilol and verapamil in human plasma samples. A dispersive liquid-liquid microextraction (DLLME) method was used for clean-up of biological samples and stacking mode of CE applied for enhancement of analyte signals in the detection process. The proposed methods were validated concerning FDA guidelines. The linear ranges for DLLME-FASI-CE-UV method were 12.5-100 ng/mL and 25-350 ng/mL for carvedilol and verapamil, respectively. In conclusion, coupling new microextraction clean-up method, i.e. DLLME, with CE, was successfully applied in the monitoring of some cardiovascular drugs enantiomers in complex plasma samples.