LAUSR

Abstract In this study, a miniaturized solid-phase extraction based on 2-(hexyloxy) naphthalene-sulfate doped polyaniline polymer as a new nanostructured sorbent packed into a 200 μL pipette tip (PT-SPE) as a rapid and efficient method was developed for the simultaneous and selective extraction of three sulfonamide (SAs) antibiotics in aqueous solution. The resultant polymer was well characterized by FT-IR, UV–Vis., FESEM, EDX and XRD. In this strategy, the pipette tip containing the sorbent was matched to a syringe and the sample solution was loaded onto the sorbent using a microsyringe pump. The eluate was analyzed with high performance liquid chromatography using UV–Vis. spectrometry detection (HPLC/UV–Vis). In preliminary experiments, sample pH, sorbent dosage, sample volume and eluent volume were identified as critical variables affecting the solid phase micro-extraction of SAs by the developed sorbent. The response surface methodology (RSM) based on a rotatable central composite design (CCD) was employed for modeling the chromatographic peak areas of SAs as responses and optimized the effective extraction variables. This method is cost-effective because only 7.4 mg sorbent amount and 0.6 mL methanol as eluent were required for the extraction of analytes. The multiple response criteria were used to optimize simultaneous responses of the analytes using the desirability function. Under the optimal conditions, a good linear relationship between the peak areas and concentrations of the SAs was found in the range of 50–50,000 ng mL−1 with correlation coefficients above 0.999. The developed method was successfully applied to the analysis of SAs in milk, and honey samples.