Self-assembled benzyl mercaptan monolayer as a coating in electromembrane surrounded solid-phase microextraction of antihistamines in urine and plasma samples

Abstract

A new solid-phase microextraction (SPME) sorbent based on the formation of a self-assembled monolayer of benzyl mercaptan on a copper wire is used in an electromembrane surrounded solid phase microextraction (EM-SPME) method. To evaluate the method performance, naphazoline (NAP) and antazoline (ANT) were selected and extracted as model analytes. An organic solvent was impregnated in the pores of the hollow fiber (HF) wall and the SPME fiber was placed in the HF lumen that was initially filled with the aqueous acceptor phase. Then, 100 V electrical potential was applied for 15 min to make the analytes migrate from the sample solution and adsorb onto the SPME fiber. Effective parameters on the extraction efficiency of the analytes, such as composition of the organic liquid membrane, pH of the donor and acceptor phases, applied voltage, and extraction time were investigated and optimized. Extraction recoveries in the range of 10.1–20.9% and good detection limits (less than 8.0 ng mL⁻¹) were obtained. Linearity of the method was obtained in the range of 4.0–100.0 ng mL⁻¹ and 3.0–100.0 ng mL⁻¹ for ANT and NAP, respectively (r² > 0.9947). Finally, the optimal conditions were applied for analysis of human urine and plasma samples and acceptable results were obtained.