Development Of Methods For Quantitation And Confirmation Of Flunxin In Animal Derived Food

Non-steroidal anti-inflammatory drugs (NSAIDs) have many effects,such as anti-rheumatism, anti-inflammatory, analgesic, antifebrile and a variety of cancer pain relief effect. It is reported that flunixin after antibiotic on usage.However, there were about 30% adverse reactions accompanied in the process of using.NSAIDs could lead to gastrointestinal damage, liver, kidney and angiocarpy adverse reactions.Flunixin as a new NSAIDs plays an important role in the disease development and prognosis, there is a great demand in the veterinary clinic.Given the use of NSAIDs is accompanied by many adverse reactions,the European Union and the United States Food Administration have developed a flunixin maximum residue limits (MRLs) in animal tissue, the United States have a determination by liquid chromatography and liquid NSAIDs chromatography-mass spectrometry method in milk, and a determination by HPLC-UVD method in beef.However, few methods have been reported for the analysis of flunixin in animal liver, kidney and fat. Therefore, the aim of this work was to develop a relatively rapid sample preparation and sensitive LC-MS/MS confirmatory method to detect flunixin residues in liver, kidney, muscle and fat of swine and chicken. After acid hydrolysis, the sample was extracted with ethyl acetate. The extract was finally evaporated to dryness and reconstituted in a water/methanol mixture and determination was carried out by LC-MS/MS. Flunixin was detected using positive electrospray ionization in multiple reaction monitoring (MRM). In this method a parent ion (m/z 297.3) and two product ions (corresponding to m/z 279.1 and 264.0) are monitored for flunixin. Estimated limit of quantification of the method was 0.5, 0.5,0.25 and 0.05 ? g/kg for liver, kidney, muscle and fat, respectively. The method was validated in animal tissues, according to the Commission Decision 2002/657/EC criteria in terms of specificity, linearity, trueness, precision, decision limit (CC a) and detection capability (CC ?). All the trueness values fell within a range between 73.6% and 84.8%. Precision values for all levels of concentration tested showed excellent relative standard deviation (RSD<15%). The CC a and CC ? values have been established for each tissue. A relatively rapid and sensitive LC-MS/MS method for the quantitative determination of flunixin in different animal tissues was developed and validated. The method is suitable for monitoring the flunixin residues in animal tissues.Meanwhile, the method successfully fulfilled the minimum limiting level requests from various countries. The development of methods provides technical support for monitoring residues of flunixin in animal derived food.