中文摘要：

以莱克多巴胺为模板分子,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸酯为交联剂,合成了对莱克多巴胺具有高选择性的分子印迹聚合物。考察了甲醇、乙腈、丙酮和氯仿-甲醇与三乙胺构成致孔剂合成的聚合物性能及其形貌特征。通过正交试验优化的聚合反应配方为：1.0 mmol莱克多巴胺,4.0 mmol丙烯酰胺,20.0 mmol乙二醇二甲基丙烯酸酯,6.0 mL乙腈-三乙胺（30∶1,v/v）,50.0 mg偶氮二异丁腈。建立的基于分子印迹固相萃取-高效液相色谱测定饲料试样中莱克多巴胺的方法,在0.50～100 mg/L质量浓度范围内有良好的线性关系（r=0.999 4）;饲料试样中 1.0、10及100 mg/kg 3个添加水平的莱克多巴胺平均回收率大于80%;批内、批间测定的相对标准偏差小于10%;检出限（信噪比为3）达到0.1 mg/kg。该方法灵敏、可靠,用于饲料等复杂基质中莱克多巴胺检测的效果优于相关标准分析方法。

英文摘要：

Molecularly imprinted polymers （MIPs） with high selectivity to ractopamine （RAC） were prepared by using RAC as template, acrylamide （AM） as monomer, and ethylene glycol dimethacrylate （EGDMA） as cross-linker. The effects of four porogens （methanol, acetoni- trile, acetone, and chloroform-methanol） with triethylamine （30： l, v/v） on the recognition capability of MIPs to RAC and the morphological characteristics of the polymers were investiga- ted. Orthogonal test was used to optimize the preparation of MIPs, and the optimal compositions were as follows： I. 0 mmol RAC, 4.0 mmol AM, 20.0 mmol EGDMA, 6.0 mL acetonitrile- triethylamine （30： 1, v/v）, and 50.0 mg azobisisobutyronitrile. A high performance liquid chro- matographic method based on molecularly-imprinted solid-phase extraction （MISPE） was developed for the determination of ractopamine in feed samples. The limit of detection （ LOD, S/N = 3 ） of ractopamine was 0. I mg/kg. The linear range was 0.50 - 100 mg/L （ r = 0. 999 4）. Mean recoveries of RAC spiked in 3 kinds of feed samples at 1.0, 10 and 100 mg/kg were above 80% with the relative standard deviations of less than 10%. The clean-up efficiency of MISPE was ideal for feed samples. The method is more sensitive and reproduciable than the standard analytical method for the determination of RAC in feed matrices.