Study On Analysis Methods Of Sudan Dyes And Antibiotics Residues In Foods By SPE And HPLC-PDAD

The separation and analysis of harmful food additive residues is a hot topicin the organic contamination analysis. At present, a number of methods dealingwith the separation and analysis of harmful food additive residues have beendeveloped. This thesis concerns about analytical approach development ofSudan dyes and Tetracyclines.In this study, HPLC-PDAD was applied to analysis tetracyclines and Sudandyes. PDAD is a good detector for quantitative analysis of known substance forqualitative analysis of unknown samples. In this study, it can be got PDADChromatogram and Spectrogram in single analysis. By the analytical information, reliable result can be drawn.Firstly, a method has been developed for the rapid determination of Sudanâ… ,â…¡,â…¢,â…£in food by high performance liquid chromatography. The Sudandyes were purified using polyamide and separated on a ZORBAX SB-C₁₈column with methanol as the mobile phase and detected with HPLC-PDAD. Theflow-rate was 1.0 ml/min. The calibration curve of each Sudan dyes showedgood linearity in the range of 1～150 ng (r=0.99992～0.99997).The detection limits of each Sudan dyes was 0.1 ng.The recovery rate was 94.8％～97.2ï¼…. Thismethod is simple, rapid, accurate and reliable.Secondly, a high performance liquid chromatography method has beenestablished for determination of Tetracycline(TC), Oxtetracycline(OTC),Chlortetracycline(CTC) and Doxyeycline(DC) in a test. Tetracyclines weresuccessfully separated on an AICHROM^TM C₁₈, (4.6×250 nm, 5μm), usingAcetonitrile: Methanol: 0.01 mol/L Oxalic acid (20:10:70, volume ratio) asmobile phase at a flow rate of 1.0 mL/min, detected by photo diode arraydetector at 365 nm, under 30℃, injecting 10μL each time.Thirdly, the tetrcyclines were extracted into a buffer solution, to provide forthe sample enrichment and clean up, then were cleaned up by Oasis HLB SPE.Recoveries exceeded 80.12ï¼…for all tetracyclines at all levels. Correlationcoefficients of standards curves for TC, OTC, CTC and DC ranged from 0.9991to 0.9999. The limits of detection of the method were all below 0.05 mg/kg,it can be applied to routine surveillance programs.Detecting different foods such as pig meat, chicken and honey by thismethod. The recoveries are between 81.2％～95.8ï¼…and the RSD is between6.28％～0.89ï¼…. The procedure is rapid, precise, and requires minimal preparationand organic solvents, The results show that this method is accurate, rapid andsimple, suitable for micro analysis in food.