Detection Of Anabolic-Androgenic Steroids And Study On Organophosphorus Pesticide Standard Materials In Food Safety

Food is the material base of a human survival and development, is the most important livelihood of people. Food safety is directly related to people's health and development of the country'stability. With the development of living standards, people's awareness of food safety is becoming more and more stronger, but there are sill a number of food safety problems, such as plants and animal veterinary drugs residues. Therefore, it is significative to establish food safety-related measurement techniquesA pretreatment method for simultaneous extraction/preconcentration (boldenone, nandrolone, methandienone, methyltestosterone, testosterone propionate, nantrolone propionate) was studied and optimized. Acetonitrile was used as extraction solution, the extraction was repeated three times by ultrasound, then combined the supernatant and frozeded for 30 minutes at-20℃, which was then centrifuged with 10000 RPM at 4℃, the centrifugal liquid was filtered by a 0.2μm membrance filter. The pretreatment method was simple, rapid, and appropriate for the pretreatment requirement of nabolic-androgenic steroids residues analysis in beef, which can also provide reference for other matrix pretreatment.A HPLC method for the simultaneous separation and detection (boldenone, nandrolone,methandienone, methyltestosterone, testosterone propionate, nantrolone propionate) was studied and optimized. Separation and quantification were achieved by using a reversed-phase analytical column(Hypersil Gold,250×4.6mm,5μm) and column temperature was at 30℃, the gradient elution solvents of water and methanol at a flow rate of 1.0 mL/min were used, photodiode array detector was monitor at 245 nm, an external method was used as the quantitative method. A linear relationship(R>0.9992) between 0.25 to 10.0mg/L was observed. Recoveries of 6 compounds ranged from 84.1% to 100.2%. LOD and LOQ of the method ranged from 5.1 to 8.6μg/kg and from 22.0 to 28.7μg/kg, respectively. The established method was reproducible, reliable, and appropriate for the analytical requirement of nabolic-androgenic steroids residues analysis in beef, which can also provide reference for the quanlity inspection and monitor.A liquid chromatography tandem mass spectrometry method for the simultaneous separation and detection (boldenone, nandrolone, methandienone, methyltestosterone, testosterone propionate, nantrolone propionate) was studied and optimized. Separation was achieved by using an analytical column (Hypersil Gold,150×2.1mm,5μm) and the gradient elution solvents of 0.1% formic acid-acetonitrile, and monitored with ESI quadrupole mass spectrometry. Under optimal chromatographic and mass spectrometry conditions, a linear relationship(R>0.995) between 0.05 to 100.0 mg/L was observed recoveries of the 6 compounds ranged from 94.8% to 109.3%. LOD and LOQ of the method ranged from 9.1×10-3 to 0.46μg/kg and from 0.303 to 0.4604μg/kg, respectively. The established method was reliable, rapid and high sensitivitive. The mass spectrometry prefers to scan the characteristic ion,which was more specificity, more quantitatively accurate, and can reach a lower LOD, was significant to trace detection.Six pesticides standard materials(methanol solution of parathion-methyl, methanol solution of dichlorvos, methanol solution of trichlorfon, methanol solution of parathion, methanol solution of dimethoate, methanol solution of malathion) were prepared by weight method,and monitored by gas chromatography. As a result, the six pesticides standard materials were stable, accurate and reliable, which can be used as the basis for pesticide detection.