基于分子印迹整体柱的在线固相萃取-液相色谱联用测定奶粉中四环素类兽药残留

Determination of tetracycline veterinary drug residues in milk powder by on-line solid phase extraction coupled with high performance liquid chromatography with molecularly imprinted monolithic column

中文关键词:  分子印迹整体柱  在线固相萃取  奶粉  四环素类抗生素  兽药残留

英文关键词:molecularly imprinted monolithic column  on-line solid phase extraction  milk powder  tetracyclines antibiotics  veterinary drug residues

中文摘要:

      目的 建立高交联结构的分子印迹整体柱(molecularly imprinted polymer monolithic column, MIP-MC)制备方法, 利用在线固相萃取与液相色谱联用技术检测奶粉样品中四环素类兽药残留。方法 在不锈钢色谱柱中, 以土霉素为模板, 甲基丙烯酸和甲基丙烯酸羟乙酯为功能单体, 乙二醇二甲基丙烯酸酯和双季戊四醇六丙烯酸酯为交联剂, 偶氮二异丁腈为引发剂, 在丙酮-甲醇-十二醇混合溶剂中, 制备了分子印迹整体柱。将整体柱与液相色谱联用, 在线固相萃取奶粉中的四环素类兽药残留。结果 在最佳在线固相萃取条件下, 获得了较高的富集因子(19.3)和净化效果。四环素类在0.05、0.25和0.5 mg/kg 3个加标水平下, 回收率为84.2%~103.4%, 相对标准偏差为1.37%~4.87%, 方法检出限(S/N=3)和定量限(S/N=10)分别为8.48~11.74 mg/kg和28.24~39.09 mg/kg。结论 该在线固相萃取方法简单快速、灵敏性高、选择性好, 适用于奶粉中四环素类抗生素残留的测定。

英文摘要:

      Objective To establish a preparation method of molecularly imprinted polymer monolithic column (MIP-MC) with the high cross-linking structures, and determine the tetracyclines residues in milk powder by on-line solid-phase extraction coupled with high performance liquid chromatography (SPE-HPLC). Methods The MIP-MC was prepared in a stainless steel column using oxytetracycline as the template, methacrylic acid and hydroxyethyl methacrylate as functional monomers, ethylene glycol dimethacrylate and dipentaerythritol hexaacrylate as the cross-linking agent, azobisisobutyronitrile as initiator, and acetone-methanol-dodecanol as porogenic solvent. The obtained monolith was applied to the determination of tetracycline drugs residues in milk powder by SPE-HPLC. Results An enrichment factor of 19.3 along with a good sample clean-up effect was obtained under optimum on-line solid phase extraction conditions. The recoveries of tetracyclines at 0.05, 0.25 and 0.5 mg/kg were in the range of 84.2%~103.4% with the relative standard deviation of 1.37%~4.87%. The limits of detection (S/N=3) and quantitation (S/N=10) of the proposed methods were 8.48~11.74 mg/kg and 28.24~39.09 mg/kg, respectively. Conclusion The on-line solid phase extraction method is simple, rapid and highly sensitive, and it is suitable for the determination of tetracyclines antibiotics residues in milk powder.