Determination of tiamulin residue in pork and chicken by solid phase extraction and HPLC

Abstract

A high performance liquid chromatography (HPLC) was developed for determining tiamulin residue in chicken and pork. Samples were extracted with acetonitrile, purified by liquid partition separation, and extracted with n-hexane at last. The n-hexane extract was concentrated and eluted through a Bond Elut C18 cartridge for HPLC analysis. The HPLC system was performed on a Lichrospher 100 RP-18 column (5 μm, 4.6 mm I.D. × 250 mm) using a mixture of 80% acetonitrile and 1% ammonia carbonate (90:10, v/v) as mobile phase, and detecting wavelength was set at 210 nm with an UV-Vis detector. The calibration curve (R2 = 0.9995) of tiamulin was highly linear at concentrations of 0.5-8.0 ppm, while the detection limit was 0.025 ppm. Recoveries of tiamulin spiked in chicken and pork samples ranged from 84.3-97.0% and 87.9-105.9%, respectively. Each 10 chicken and pork samples sold in retail markets were tested to detect tiamulin, while none of these samples contained tiamulin.