表面分子印迹固相萃取微球的制备及其在谷氨酸分离检测中的应用

以L-谷氨酸为模板分子、2-丙烯酰胺-2-甲基丙磺酸为功能单体、N, N-亚甲基双丙烯酰胺为交联剂，采用可逆加成-断裂链转移活性自由基聚合法制备表面分子印迹固相萃取(MISPE)微球，并对制备的印迹微球进行傅立叶变换红外光谱、扫描电镜、热重分析等表征.萃取实验结果表明:该微球可实现L-谷氨酸的选择性分离富集，萃取容量为140 μg/g.结合MISPE方法与高效液相色谱检测技术，可实现酱油中L-谷氨酸的快速分析检测，线性范围为1.47~58.9 μg/mL，检出限为44.1 ng/mL，加标回收率为77.8%~82.2%.

Preparation of Microspheres for Molecularly Imprinted Surface Solid Phase Extraction and its Application in the Separation and Detection of Glutamic Acid

Molecularly imprinted solid-phase extraction (MISPE) microspheres were prepared using L-glutamic acid, 2-acrylamido-2-methyl propane sulfonic acid and N, N-methylene bis-acrylamide as template, functional monomer and cross-linker respectively and using the reversible addition-fragmentation chain transfer polymerization. Then the imprinted silica gel microspheres were characterized with Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric analysis (TG). The results of the extraction experiment showed that MIPs exhibited excellent performance in separating glutamic acid from soy sauce, and an extraction capacity up to 140 μg/g was achieved. The rapid analysis of L-glutamic was realized by combining MISPE with high performance liquid chromatography technology. The linearity of L-glutamic acid was 1.47~58.9 μg/mL and the detection limit was 44.1 ng/mL. The recovery rate was 77.8%~82.2%.