分子印迹分散固相萃取-液相色谱串联质谱法测定尿液中克仑特罗

为了快速检测尿液中的痕量克仑特罗，以克仑特罗分子印迹聚合物为吸附剂，建立了基于分子印迹的分散固相萃取液质联用测定尿液中克仑特罗检测方法。样品用分子印迹聚合物吸附，甲醇/乙酸/水(7/2/1)洗脱，氮气吹干后用0.1%甲酸水/甲醇(9/1)溶液定容，过0.22 μm滤膜后可进行LC-MS/MS分析。结果表明，分子印迹聚合物对克仑特罗有良好的结合性，在0.2~25 μg/L质量溶液范围内有良好的线性关系(r=0.9992)，检出限(S/N=3)为0.08 μg/L，定量限为(S/N=10)为0.2 μg/L，在0.2、1.0、2.0 μg/L 3个添加水平的克仑特罗回收率大于70.2%；相对标准偏差小于4.16%。方法分析速度快、灵敏度高、重现性好、试剂用量少、无基质干扰，可用于尿液中克仑特罗的检测。

Determination of Trace Clenbuterol Residue in Swine Urine by LC-MS/MS with Dispersive Solid Phase Extraction using Molecular Imprinted Polymer as Adsorbent

In order to detect trace clenbuterol in swine urine, a method was developed by liquid chromatography tandem mass spectrometry with dispersive solid phase extraction using molecular imprinted polymer as adsorbent. The samples were absorbed by molecularly imprinted polymer. After eluted with methanol/acetic acid/water (7/2/1), the eluate was evaporated to dryness under a nitrogen stream and dissolved in 0.1% formic acid water/methanol (9/1). The extract was filtered through 0.22 μm filter, and 5 μL filtrate was injected into LC-MS/MS for analysis. The experiment results showed that MIP had specific recognition selectivity, excellent binding affinity and elution property for clenbuterol. Good linearity was obtained for clenbuterol at the concentration of 0.2-25 μg/L with correlation coefficient of 0.9992. The detection limit(S/N=3) and quantification limit(S/N=10) of the proposed method for clenbuterol was 0.08 μg/L and 0.2 μg/L. The recoveries of clenbuterol in swine urine at 0.2, 1.0, 2.0 μg/L were above 70.2% with the relative standard deviation of less then 4.16%. The method was reliable, sensitive, reproducible, less reagent dosage and no matrix interference, so it could meet the requirement for determination of the clenbuterol in swine urine.