Investigation Of Separation And Determination Of β-agonist

Beta agonist(beta adrenergic agonist) is a kind of synthetic drugs named for beta stimulants. Early beta stimulants used in the treatment of bronchial asthma in animals and humans, cramps and premature delivery, has played a positive role in medical disease. Since it promote growth, increase animal carcass muscle content was as feed additive used in livestock breeding. The illegal use had caused it entering the human body through the food chain and thus caused poisoning in some country of European Union and China.For the sake of food safty and public health it has been banned as feed additive in our country.This paper established a gas chromatography(GC)- mass spectrometry(MS) method to detect the beta agonist residues in animal tissues. Respectively, the extraction, cleaning, derivatization, chromatographic conditions, and mass spectrum conditions are investigated fot the separation and determination of four beta agonist. And then a method of GC – MS method is established for detecting residues of beta agonist in pork tissues. The optimised Gas chromatographic conditions: Elite- 35 MS quartz capillary column(30 m *0.25 mm, 0.25μm), the injection temperature is 250 ℃, helium(99.999%), the flow rate of 1.0 m L/min constant current mode, programmed temperature:80 ℃ �'12 ℃ /min �'220 ℃(5min) �'12 ℃/min�'280℃(10 min), Sample volume:1μL; and mass spectrometry conditions: EI source, 70 EV; Quality range: 30 ~ 400 amu; Ion source temperature: 280 ℃; Transmission line temperature: 220 ℃; The carrier gas is helium(99.999%). For determination of clenbuterol in pork and liver tissue of, the linear regression equation is Y=0.8167X+0.7549, the correlation coefficient of 0.9979; linear range 0.5 ~ 5μg/㎏, detection limit : 0.1 g / ㎏, recovery of 80.58 ~ 97.87%;determination of ractopamine in pork tissues, liver, linear equation is Y = 0.5536 X + 0.5536, correlation coefficient of 0.9968, the linear range of 0.5 ~ 5μg/㎏, detection limit :0.2 g / ㎏, relative recovery : 72.66 ~ 93.87%;determination of salbutamol in pork tissues, the linear equation is Y = 0.4856 X + 0.4856, correlation coefficient of 0.9956, linear range of 0.5 ~ 5μg/㎏, detection limit :0.2 g / ㎏, relative recovery : 81.66 ~ 95.78%;and determination of liver Isoxsuprine In pork tissues, linear equation is Y = 0.5065 X + 0.5065, correlation coefficient of 0.9979, the linear range of 0.5 ~ 5μg/㎏ detection limit :0.2μg/㎏, relative recovery :72.76 ~ 96.24%.Using this method detecting residues of clenbuterol,ractopamine,salbutamol and isoxsuprine in pork tissues and liver, the results shows the method is good sensitivity, accurate and reliable.