Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, P.O. Box No.45, Agricultural Building, 800 Dongchuan Road, Minhang District, Shanghai 200240, China.
Anal Bioanal Chem. 2011 Oct;401(7):2259-73. doi: 10.1007/s00216-011-5282-y. Epub 2011 Aug 27.
A new molecularly imprinted polymer (MIP) has been prepared on silica beads using the radical "grafting from" polymerization method for selective extraction of minor contaminant mycotoxin of patulin (PTL). After the introduction of amino groups onto the silica surface with 3-aminopropyltriethoxysilane, azo initiator onto the silica surface was achieved by the reaction of surface amino groups with 4,4'-azobis(4-cyanopentanoic acid). The scale-up synthesis of MIP was then carried out in the presence of 6-hydroxynicotinic acid as template substitute, functional, and cross-linking monomers. The prepared sorbent was characterized using FT-IR spectroscopy, scanning electron microscopy, elemental analysis, and the adsorption-desorption selectivity, and the capacity characteristic of the polymer was investigated by a conventional batch adsorption test and Scatchard plot analysis. The results indicated that coated polymers had specific adsorption to PTL as compared with its co-occurring 5-hydroxymethyl-2-furaldehyde (hydroxymethylfurfural (HMF)), at the same bulk concentration for solution of PTL and HMF, the maximum absorbance in the solid-phase extraction (SPE) method to PTL were 93.97% or 0.654 μg/mg while to HMF they were 76.89% or 0.496 μg/mg. Scatchard analysis revealed that two classes of binding sites were formed in PTL-MIP with dissociation constants of 3.2 × 10(-2) and 5.0 × 10(-3) mg/mL and the affinity binding sites of 8.029 and 1.364 mg/g, respectively. The recoveries of PTL were more than 90% for the developed MISPE and around 75% for the traditional liquid-liquid extraction in spiked apple juice samples. It was concluded that the method is suitable for the scale-up synthesis of PTL-MIP grafted on silica, and the polymer can be effectively applied as SPE coupled with high-performance liquid chromatography (HPLC) for the determination of PTL in apple juice or other related products.
一种新的分子印迹聚合物（MIP）已在硅胶珠上通过自由基“从”聚合方法制备，用于选择性提取微量污染物展青霉素（PTL）的真菌毒素。用 3-氨丙基三乙氧基硅烷在硅胶表面引入氨基后，通过表面氨基与 4,4'-偶氮双（4-氰戊酸）反应，在硅胶表面上实现偶氮引发剂。然后，在 6-羟基烟酸作为模板替代物、功能和交联单体的存在下进行 MIP 的规模化合成。通过傅里叶变换红外光谱、扫描电子显微镜、元素分析以及吸附-解吸选择性对制备的吸附剂进行了表征，并通过常规批量吸附试验和 Scatchard 图分析研究了聚合物的容量特性。结果表明，与共存的 5-羟甲基-2-糠醛（羟甲基糠醛（HMF））相比，涂覆聚合物对 PTL 具有特异性吸附，在相同的 PTL 和 HMF 溶液体浓度下，固相萃取（SPE）方法中 PTL 的最大吸光度为 93.97%或 0.654 μg/mg，而 HMF 的最大吸光度为 76.89%或 0.496 μg/mg。Scatchard 分析表明，在 PTL-MIP 中形成了两类结合位点，解离常数分别为 3.2×10(-2)和 5.0×10(-3)mg/mL，亲和结合位点分别为 8.029 和 1.364 mg/g。在添加苹果汁样品中，开发的 MISPE 的 PTL 回收率均超过 90%，而传统液液萃取的回收率约为 75%。结果表明，该方法适用于在硅胶上接枝 PTL-MIP 的规模化合成，并且该聚合物可有效应用于与高效液相色谱（HPLC）结合的 SPE 用于测定苹果汁或其他相关产品中的 PTL。
