Voltammetric determination of lercanidipine in urine, blood plasma, and serum using hollow fiber-based liquid phase microextraction

This study investigates a synergistic combination of hollow fiber-based liquid phase microextraction (HF-LPME) and voltammetric analysis using screen-printed boron-doped diamond electrodes (SP-BDDE) for the determination of antihypertensive drug lercanidipine (LCN) in urine, blood plasma, and blood serum. Optimum HF-LPME conditions were: dodecane as supported liquid membrane, Britton-Robinson buffer (BRB) pH 7 as donor solution, BRB pH 3 as acceptor solution, and extraction time 30 min. Square-wave voltammetry (SWV) of 10 μL acceptor solution at SP-BDDE was utilized with amplitude 75 mV, frequency 10 Hz, and potential step 4 mV. The calibration dependence of the combined HF-LPME-SWV method was established in the range of 1-1000 nmol L^-1, with limits of quantification (LOQ) and detection (LOD) of 3.3 and 1.1 nmol L^-1, respectively. The applicability of the developed method was verified by analysis of human urine, blood plasma, and blood serum samples spiked with 20 and 100 nmol L^-1 LCN with recoveries ranging from 93.2 to 112.9 % with respective RSDs 1.72-8.5 % (n = 3).