Study On Determination Of Veterinary Drug Residues In Food Using HPLC And HPLC-MS

The safety of animal food is related not only with international food trade, but also with the health of public. Nowadays the wide utilization of diversified veterinary drugs brings tremendous economic benefits for animal breeding. However, it can also cause many kinds of drug residues in animal food after a long-time over-dosage utilization of veterinary drugs. One important measure of inspection of drug residues in animal foods is to develop a fast and accurate method for the determination of these drug residues. This thesis is trying to develop methods to determine different drug residues in animal foods.The methods of determining 17 sulfonomides in casing with HPLC-MS, amitraz and 2, 4-dimethylaniline in honey and royal jelly with HPLC and HPLC-MS, salbutamol, clenbuterol and ractopamine in pork with HPLC-MS were developed.Casing sample was extracted with 1:1 acetonitrile and ethyl acetate. The extraction was evaporated with rotary evaporator until dry, then 3:7 methanol and pure water was used to dissolve the matters of interest. The solution was filtered through a 0.45μm membrane and then analyzed. Internal standard was used for quantification.Honey and royal jelly samples were basified followed by extraction with 10:3 hexane and isopropyl alcohol. The extraction was evaporated with rotary evaporator until dry, HPLC-grade acetonitrile and pure water were separately used to dissolved the matters of interest. The solution were mixed and filtered through a 0.45μm organic membrane and then analyzed with HPLC or HPCL-MS. External standard method was used for quantification.After hydrolyzed withβ-glucuronidase and arylsulfatase, the pork sample was extracted with 5% perchloric acid. The extraction was adjusted to alkaline with ammonia, then 4:6 acetonitrile and ethyl acetate was used to reextracted residue drugs. The extraction was evaporated with rotary evaporator until dry followed by addition of 10% formic acid to dissolve the leavings. The solution was purified using MCX SPE catridge. Then the elution solution was blew with nitrogen until dry followed by dissolvation with 1 mL of methanol/water/formic acid (30:70:0.5). The solution was filtered through a 0.45μm membrane and then analyzed. Internal standard was used for quantification.The HPLC-MS instrument methods of determining drug residues mentioned above were developed and the methods parameters were optimized. The HPLC instrument method of determining amitraz and 2, 4-dimethylaniline was developed. The recovey experiment and precision experiment showed that, the recovery concentrated in70%~100%, when the concentration was above 10μg/ kg, the RSD was mostly below 10.6%. The recovery of amitraz was between 66.2% and 75.7% in honey, between 59.8% and 65.0% in royal jelly. The recovery of 2, 4-dimethylaniline was between 60.3% and 70.2% in honey , between 61.9% and 65.5% in royal jelly. The RSDs were all below 12.6%. The recovery of salbutamol was between 72.4% and 96.4% with RSD<8.2%, clenbuterol was between 93.0% and 97.0% with RSD<0.9% and ractopamine was between 96.4% and 100.1% with RSD<10.3%. The methods are rapid and accurate and are fit for daily analysis and confirmation.