以金溶胶作为活性基底, 浓度为1%的NaCl溶液作为活性剂, 利用DXRTM显微拉曼光谱仪采集鸡肉的表面增强拉曼光谱(SERS), 实现快速鉴别鸡肉中残留的磺胺二甲基嘧啶(SM-2)和磺胺吡啶(SPD)两种抗生素。 用937和1 188 cm-1处是否有拉曼特征峰来判别鸡肉中是否残留SPD和SM-2。 采用单因素实验方法, 根据937和1 188 cm-1处的特征SERS强度, 对试验条件进行优化, 得到最佳试验条件: 金溶胶加入量为500 μL、 NaCl溶液加入量为100 μL和吸附时间为5 min, 所选用的金溶胶柠檬酸钠加入量3.7 mL。 根据测试集鸡肉中残留的SM-2和SPD的分类精度确定研究用自适应迭代惩罚最小二乘法(air-PLS)、 归一化和二阶导数作为原始拉曼光谱的预处理方法, 然后用主成分分析(PCA)提取特征向量, 最后以前四个PCA得分值作为支持向量机(SVM)分类模型的输入值, 建立基于C-SVC类型的SVM分类模型。 其中, 最优惩罚参数c为0.01、 核参数g为0.1。 此分类模型对测试集的整体分类精度达到93.23%。 对测试集的敏感性和特异性进行计算, 敏感性的范围为77.42%~100%, 特异性的范围为96%~99.02%, 其中, 含SM-2+SPD鸡肉的敏感性最高为100%, 含SPD鸡肉的特异性最高为99.02%。 试验结果表明, 该方法具有良好的鉴别效果, 可用于实现对鸡肉中SM-2和SPD两种抗生素残留的快速检测和鉴别。

Surface-enhanced Raman spectroscopy (SERS) of chicken was collected by DXRTM micro-Raman spectrometer with gold colloid as an active substrate and NaCl solution as the active agent. Rapid identification of sulfadimidine (SM-2) and sulfadiazine (SPD) residues in chicken was achieved. Raman peaks at 937 and 1 188 cm-1 were used to determine whether there are SM-2 and SPD in chicken or not. The Single-factor experiment method was used to optimize the experimental conditions, and the optimum experimental conditions were obtained: the addition amount of Gold glue was 500 L, the addition amount of NaCl solutionwas 100 L and the adsorption time was 5 minutes. The original Raman spectra were pre-processed by adaptive iterative penalty least squares (air-PLS), normalization and second derivative. Then the eigenvectors were extracted by principal component analysis (PCA). Finally, the first four PCA scores were used as input values of the support vector machine (SVM) classification model, and the SVM classification model based on C-SVC type was established. The optimal penalty parameter c was 0.01, and the kernel parameter g was 0.1. The overall classification accuracy of the model was 93.23%, the sensitivity of chicken containing SM-2+SPD was 100%, and the specificity of chicken containing SPD was 99.02%. The results showed that this method had good identification effects. It could be used to detect and identify SM-2 and SPD antibiotic residues in chicken quickly.