新型SERS基底的制备及其奶制品中残留抗生素的检测研究

In this paper, the programs of using surface enhanced Raman spectroscopy (SERS) to detect the residue of ampicillin, tetracycline hydrochloride, sulfamethazine and other antibiotics and their degradation products were proposed. Firstly, three novel SERS substrates of different functions were designed and prepared by the self-assembly technology of liquid-liquid interface of metal nanoparticles, and the enhancement mechanism of the substrates was studied. Secondly, the molecular vibration mode of antibiotic was assigned by combining theoretical simulation with experimental measurement, and then the Raman spectrum information database was established. The new SERS substrate was then used to detect the antibiotic residues in dairy products and to conduct qualitative and quantitative analysis. Finally, the degradation products of residual antibiotics in dairy products were detected, and the degradation mechanism of antibiotics was explored, so as to establish a complete monitoring and detection system for antibiotics and their degradation products. The method has the advantages of in situ, rapid, accurate, nondestructive and trace detection.

提出了利用表面增强拉曼光谱（SERS）技术检测奶制品中残留的氨苄青霉素、盐酸四环素、磺胺二甲基嘧啶等抗生素及其降解产物的方案。首先基于金属纳米颗粒的液液界面自组装技术，设计制备三种不同功能的新型SERS基底，并对其增强机制进行研究；其次理论模拟与实验测定相结合，对抗生素分子振动模式进行归属，进而建立拉曼光谱信息库；然后使用新型的SERS基底检测奶制品中残留的抗生素，并对其进行定性和定量分析；最后检测奶制品中残留的抗生素的降解产物，并探索抗生素的降解机理，进而建立完整的抗生素及其降解产物的监控检测体系。该方法具有现场、快速、准确、无损、痕量检测等优点。

抗生素的广泛而大量的使用对人们的身体健康带来越来越大的威胁。然而，食品中抗生素的来源广泛，起因复杂，加大了食品中抗生素残留监管的难度，这需要采用更加精密的仪器和手段加以检测。针对上述问题，本项目提出了利用表面增强拉曼光谱（SERS）技术检测奶制品中抗生素残留的方案，该方法具有快速、灵敏、准确、无损、低成本等优点。首先制备了不同形貌、不同尺寸的银纳米、金纳米和金银核壳纳米结构SERS基底，并以液/液界面自组装技术将其组装到聚二甲基硅氧烷（PDMS）、热收缩聚苯乙烯（TSP）、滤纸、硅片等衬底上制备了多功能固态SERS基底，对其光学特性进行了表征，并分析了SERS增强机制。然后使用所制备的新型SERS基底检测了奶制品中多种抗生素残留，拟合了特征峰强度随浓度的线性变化曲线，计算分析了回收率及相对标准误差，进而实现了奶制品中抗生素残留的快速检测。最后提出了SERS技术结合主成分分析（PCA）-支持向量机（SVM）对奶制品中抗生素及其降解产物残留的分类鉴别方案。结果表明，该方法能够有效的提取拉曼光谱的全部信息，从而进行准确的分类鉴别，避免了人工识别所带来的主观性。与依据个别拉曼峰值的表面信息来识别的传统分析方法相比，该方法更全面、更深入、更科学、更具有统计学意义。