Simultaneous Determination of Four Tetracycline Antibiotics Residues in Chicken by Solid Phase Extraction Coupled with High Performance Liquid Chromatography

Objective- To establish a simple and rapid method for simultaneous determination of Tetracycline, Oxytetracycline, Chlortetracycline and Doxycycline in chicken. Methods- After optimized sample pretreatment and chromatographic conditions, tetracycline antibiotics in spiked chicken were extracted by ultrasonic extraction with Na2EDTA-Mcllvaine buffer solution (pH=4.0), purified and enriched by HLB solid phase extraction column, separated by Shim-pack GIST C18 column (4.6×150 mm, 3 μm), methanol-acetonitrile-oxalic acid (1-2-7, V- V- V) as the mobile phase, the flow rate was 0.9 mL/min, the UV detection wavelength was 350 nm, and the peak area was quantified by external standard method. Results- The linearity of the four tetracycline antibiotics was good in the range of 0.05-1 mg/kg (r＞0.997), and the detection limits were 2.53 μg/kg ~ 5.94 μg/kg according to the S/N ratio (S/N) of 3. The relative standard deviations (RSD, n=6) of precision were 1.51%-4.80%. The recoveries were from 76.81% to 96.34%. Conclusion- The method has good selectivity, high accuracy and reproducibility, and is suitable for simultaneous determination of four tetracycline antibiotics in chicken.