Li Ya-hui, Yang Tao, Qi Xiao-ling, Qiao Yu-wei, Deng An-ping
College of Chemistry, Sichuan University, Wangjiang Road 29, Chengdu 610064, China.
Anal Chim Acta. 2008 Aug 29;624(2):317-25. doi: 10.1016/j.aca.2008.07.004. Epub 2008 Jul 12.
A group selective molecularly imprinted solid phase extraction (MISPE) for malachite green (MG) from fish water and fish feed samples was developed. Using MG as template molecule, methacrylic acid as functional monomer, ethylene glycoldimethacrylate as linking agent and bulk polymerization as synthetic method, the molecularly imprinted polymers (MIPs) were synthesized and characterized with rebinding experiment. The Scatchard polt's analysis revealed that the template-polymer system showed the two-site binding behavior with dissociation constants of 0.3194 micromol L(-1) and 15.70 micromol L(-1), respectively. MG and two structurally related compounds, leucomalachite green (LMG) and crystal violet (CV) were employed for selectivity test. The MIPs exhibited the highest selective rebinding to MG, but also displayed 83.0% and 87.5% of cross-reactivity with LMG and CV, demonstrating that MIPs could be used as group recognition sorbents in solid phase extraction. The extraction conditions of MISPE column for MG were optimized. Tap water samples spiked with MG at concentration of 0.5-10 ng mL(-1) were extracted by MISPE column and analyzed by high performance liquid chromatography. The recoveries of MISPE column for MG extraction were found to be 76.8-93.7% with the relative standard deviations of 2.12-10.09%, indicating the feasibility of the prepared MIPs for MG extraction. No detectable MG was observed in one fish farming water sample and two fish feed samples; while the MG concentrations in two pet fishpond water samples were found at 1.50 ng mL(-1) and 0.67 ng mL(-1), respectively.
建立了一种从鱼水和鱼饲料样品中选择性提取孔雀石绿（MG）的分子印迹固相萃取（MISPE）方法。以MG为模板分子，甲基丙烯酸为功能单体，乙二醇二甲基丙烯酸酯为交联剂，采用本体聚合法合成分子印迹聚合物（MIPs），并通过再结合实验对其进行表征。Scatchard曲线分析表明，模板-聚合物体系表现出双位点结合行为，解离常数分别为0.3194 μmol L⁻¹和15.70 μmol L⁻¹。采用MG以及两种结构相关的化合物隐色孔雀石绿（LMG）和结晶紫（CV）进行选择性测试。MIPs对MG表现出最高的选择性再结合，但对LMG和CV也分别表现出83.0%和87.5%的交叉反应性，表明MIPs可作为固相萃取中的基团识别吸附剂。优化了MISPE柱对MG的萃取条件。用MISPE柱萃取加标浓度为0.5 - 10 ng mL⁻¹的自来水样品，并通过高效液相色谱进行分析。发现MISPE柱对MG萃取的回收率为76.8 - 93.7%，相对标准偏差为2.12 - 10.09%，表明所制备的MIPs用于MG萃取具有可行性。在一个养鱼水样和两个鱼饲料样品中未检测到MG；而在两个观赏鱼养殖水样中，MG浓度分别为1.50 ng mL⁻¹和0.67 ng mL⁻¹。
