tailieunhanh - Báo cáo khoa học: "Simultaneous Determination of Various Macrolides by Liquid Chromatography/Mass Spectrometry"

Tuyển tập các báo cáo nghiên cứu khoa học quốc tế về bệnh thú y đề tài: Simultaneous Determination of Various Macrolides by Liquid Chromatography/Mass Spectrometry | J. Vet. Sci. 2002 3 2 103-108 JOURNAL OF Veterinary Science Simultaneous Determination of Various Macrolides by Liquid Chromatography Mass Spectrometry Youn-Hwan Hwang Jong-Hwan Lim Byung-Kwon Park and Hyo-In Yun Division of Veterinary Pharmacology and Toxicology College of Veterinary Medicine Chungnam National University Received Jan. 4 2002 Accepted Apr. 29 2002 ABSTRACT Macrolides are frequently used in veterinary medicine as therapeutic and preventive agents for various diseases. It is difficult to determine m acrolides simultaneously with conventional methods due to their similar structures. A simultaneous an alysis for erythromycin roxithromycin tiamulin and tylo sin with LC MS has been developed. Separation was performed on C18 reversed phase column. Mobile phase was gradiently flowed with 10 mM ammonium acetate and methanol. The mass spectrometer was run in the positive mode and selective ion m onitorin g mode. The molecular ions were M H form at m z for erythromycin at m z for roxithromycin at m z for tiamulin and at m z for tylosin. Lim its of detection were in the ran ge from to g lower than their MRLs. Keywards simultaneous determination liquid chromato-graphy mass spectrometry macrolides antibiotics 1. Introduction Macrolide antibiotics have 12- 14- 16- or 17-membered macrocyclic lactone r ing which is bound to sever al amino and or neutral sugars fig. 1 . Because of their effective antimicrobial activity again st Gram-positive bacteria my-copla sma chlamydia they are fr equent ly used in industrial animals to treat and prevent diseases or as growth promotants 1 . Incorrect use of these antibiotics may leave r esidues in edible t issues cau sing t oxic effect s on consumers . aller gic reactions in hypersensitive individuals or in dir ect ly pr oblem s through the induction of resistant strains of bacteria 2 . Therefore the Sourth Korea has set maximum r esidue limit s MRLs for macrolide antibiotics in edible .