表面引发原子转移自由基聚合法制备氯霉素表面分子印迹聚合物及其应用研究

目的： 采用表面引发原子转移自由基聚合（SI-ATRP）技术合成了氯霉素表面分子印迹聚合物并应用于动物源食品中痕量氯霉素富集分析。 方法： 以2-溴异丁酰溴为引发剂，氯霉素为模板分子，甲基丙烯酸二乙基氨基乙酯（DEAEM）为功能单体，乙二醇二甲基丙烯酸酯（EDMA）为交联剂，CuBr/2，2'-联吡啶（Bpy）为催化剂，在室温下采用SI-ATRP将模板分子氯霉素印迹到硅胶表面，制得了氯霉素表面分子印迹聚合物。采用静态吸附实验和选择性实验研究了分子印迹聚合物（MIPs）对氯霉素的结合性能与分子识别特性。 结果： MIPs对氯霉素最大吸附量为0.48 mmol·g^-1，相对于结构类似物琥珀酸氯霉素、甲砜霉素和氟苯尼考的选择性系数分别为2.51、4.39和1.40，相对选择性系数分别为1.68、3.40和1.92。MIPs与固相萃取联用，对牛肉样品进行了加标回收试验，平均回收率为92.4%~98.7%，相对标准偏差为5.2%~6.2%，方法的检出限可达10 ng·g^-1。 结论： 该MIPs具有良好的吸附选择性和较高的吸附容量且结合速率快，与市售C₁₈固相萃取小柱相比，该MIPs更适合作为固相萃取吸附剂对动物源食品中的痕量氯霉素残留进行富集分析。

Objective: To prepare of chloramphenicol imprinted materials by surface-initiated atom transfer radical polymerization(SI-ATRP)and to apply then in enrichment and analysis of trace chloramphenicol residue in animal source food. Methods: In this work,the chloramphenicol surface molecularly imprinted polymers (MIPs) were firstly prepared by SI-ATRP technology.The silica gel used 2-bromoisobutyryl bromide as macroinitiator,CuBr/2,2’-bipyridine(Bpy) as the catalytic system,and the 2-(diethylamino)ethyl methacrylate (DEAEM),ethylene glycol dimethacrylate (EDMA) were chosen as the functional monomer and crosslinker,respectively.The template molecular chloramphenicol (CAP) was imprinted onto the surface of silica gel by using SI-ATRP method at room temperature. Results: The equilibrium adsorption experiment and selectivity adsorption experiment were carried out to evaluate the characteristics of the MIPs.The maximum adsorption amount of MIPs was 0.48 mmol·g^-1.The selectivity coefficients for chloramphenicol succinate,thiamphenico and florfenicol were 2.51,4.39 and 1.40,respectively,the relative selectivity coefficients for NIPs were 1.68,3.40 and 1.92,respectively.An easy method combining solid phase extraction (SPE) with MIPs was established for selective enrichment and purification of the trace amounts of CAP residues in beef samples.The recoveries of the standard added were among 92.4%-98.7%,the relative standard deviations (RSDs) were 5.2%-6.2%,and the limit of detection (LOD) in the beef samples was 10 ng·g^-1. Conclusion: The MIPs possessed large adsorption capacity,high adsorption rate and excellent enrichment effect.Compared with the commercial C₁₈ solid phase extraction cartridge,the MIP-SPE was more suitable for enrichment of the trace amounts of CAP from beef samples.