Analysis of tetracycline residues in bovine milk by CE-MS with field-amplified sample stacking.
A rapid, sensitive, and robust CE-MS method has been developed for the determination of tetracycline, oxytetracycline, and chlortetracycline in milk. Field-amplified sample stacking with electromigration injection (FASS-EMI) was used for the online concentration of tetracyclines. The conditions of separation, MS detection, and stacking were systematically optimized. The optimum buffer composition was 35 mM Tris, 1.1% formic acid, 5% methanol, and 15% ACN. By using the online concentration method of field-enhanced sample stacking (FESI)-EMI stacking, the sensitivity was increased six- to seven-fold. The RSDs (n=6) of the relative migration time of tetracyclines were 1.1-1.4% for intraday and 2.4-2.9% for interday. The RSDs (n=6) of the relative peak area of tetracyclines were 3.2-4.6% for intraday and 4.7-6.1% for interday. The LODs (S/N=3) were 7.14 ng/mL for tetracycline, 11.4 ng/mL for oxytetracycline, and 14.9 ng/mL for chlortetracycline. The method has been successfully used to analyze tetracyclines residues in bovine milk.
Wang
Shufang
S
Pharmaceutical Informatics Institute, Zhejiang University, Hangzhou, PR China.
Yang
Ping
P
Cheng
Yiyu
Y
D000818:Animals; D002021:Buffers; D002417:Cattle; D004350:Drug Residues / Q000032:analysis; D019075:Electrophoresis, Capillary / Q000379:methods* / Q000592:standards; D008892:Milk / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods* / Q000592:standards; D013754:Tetracyclines / Q000032:analysis*
D002021:Buffers; D013754:Tetracyclines