MEASUREMENT OF FLUOROQUINOLONE ANTIBIOTICS FROM HUMAN PLASMA USING HOLLOW FIBER LIQUID-PHASE MICROEXTRACTION BASED ON CARRIER MEDIATED TRANSPORT

Due to the existence of both amine and carboxylic acid groups on ofloxacin and ciprofloxacin, the direct passive transport from aqueous sample to organic solvent is difficult Therefore, the transport of the drugs was carried out in the presence of methyltriodylammonium chloride (Aliquat 336), as a carrier. The drugs were extracted from 10.0 mL of the aqueous solution which had a pH of 8.5, into the organic extracting solvent (1-octanol 10% (w/v) carrier) which had been impregnated into the pores of hollow fiber; this was followed by a back extraction into 24 mu L. aqueous solution located inside the lumen of a hollow fiber (pH 1.0, 1 mmol/L NaCl). Under the optimized conditions, the preconcentration factors (PFs) were achieved up to 137, and the relative standard deviation (RSD) of the method was less than 4.9%. The calibration curves were obtained in the ranges of 1-500 mu g/L, with a reasonable linearity (R-2 > 0.997), and the limit of detection (LOD) was 0.5 mu g/L for both of the drugs. Finally, the applicability of the proposed method was evaluated by the extraction and determination of the drugs from plasma and lap water samples.