HPLC DETERMINATION OF AMLODIPINE IN BIOLOGICAL FLIUIDS USING HOLLOW FIBER BASED LIQUID-LIQUID-LIQUID MICROEXTRACTION

Abstract

A sensitive and precise method is described for determination of amlodipine besylate (AMB) in biological samples using hollow fiber based liquid-liquid-liquid microextraction (HF-LLLME) followed by high performance liquid chromatography. Different effective parameters on extraction efficiency were studied and optimized. The analyte was extracted from 11.0 mL diluted urine and plasma samples containing 0.1 mol L-1 NaOH (donor phase) into dibenzyl ether membrane phase impregnated in the pores of the hollow fiber wall and back extracted into the 25 mu L acceptor phase (0.01 mol L-1 HCl) located inside the lumen of the hollow fiber. The analyte enriched acceptor phase was finally withdrawn into the microsyringe and directly injected into HPLC for the separation and quantification of the target analyte. The performance of the proposed method was studied in terms of dynamic linear ranges, coefficients of determination, precision, and limits of detection and quantification. The relative recoveries of AMB in plasma and urine samples were 96.4% and 97.2% with RSDs of 6.3% and 4.8%, respectively.