Liquid-phase microextraction of protein-bound drugs under non-equilibrium conditions

摘要: Recently, we introduced an inexpensive and disposable hollow fiber-based device for liquid-phase microextraction (LPME) where ionic analytes typically were extracted preconcentrated from 1–4 mL aqueous samples (such as plasma urine) through organic solvent immobilized in the pores of a polypropylene fiber into 10–25 μL volume acceptor phase present inside lumen fiber. Subsequently, was directly subjected to final analysis by chromatographic or electrophoretic method. In work, attention focused on LPME basic drugs amphetamine, pethidine, promethazine, methadone haloperidol characterized substantial differences degree protein binding. Drug–protein interactions resulted reduced recoveries substantially increased extraction times compared with pure water matrix. However, addition 5–50% methanol to samples, comparable ranged between 75 100%. The methanol found not speed up process extractions performed 45 min reach equilibrium. Because approximately 55–70% analyte concentrations achieved within initial 10 process, validation accomplished after LPME. general, results almost comparable, precision data range 1.2–11.1% (RSD) linearity concentration 20–1000 ng mL−1 (r = 0.999). conclusion, excellent may be short time under non-equilibrium conditions minor loss sensitivity. cases drug–protein interactions, added ensure high recovery.