采用薄层色谱法（TLC）与表面增强拉曼光谱（SERS）联用技术，建立猪尿中磺胺类抗生素残留的快速筛查方法。用阴性猪尿样本模拟阳性样品，以氯仿-乙醇-石油醚（1:1:2）为展开剂，利用TLC将猪尿中的抗生素与猪尿基质初步分离。以785 nm激光为激发波长，金溶胶为表面增强剂，采用SERS技术对分离出的抗生素沉积斑点进行检测。结合密度泛函理论，得到定性定量分析猪尿中磺胺嘧啶分子特征峰877 cm-1和994 cm-1、磺胺二甲嘧啶分子特征峰661 cm-1、磺胺噻唑分子特征峰862 cm-1和1127 cm-1。该方法检测猪尿中磺胺嘧啶、磺胺二甲嘧啶和磺胺噻唑的最低检测浓度分别为0.1、0.1、0.2 mg/L。且TLC技术可实现猪尿中混合抗生素的分离，当猪尿中3种混合抗生素点样沉积量为0.01 μg时，各抗生素的特征峰均清晰可辨。由此可见，TLC-SERS技术可用于猪尿中混合抗生素残留的快速筛查。

A rapid detection method for sulfonamide antibiotics residues in swine urine was developed based on thin layer chromatography (TLC) and surface enhanced Raman spectroscopy (SERS) technology. Position samples were made by antibiotics being added to negative swine urine. Chloroform-ethanol-petroleum ether (1:1:2) was used as a mobile phase to separate antibiotics from swine urine. The excitation wavelength was 785 nm. Gold colloidal was used to enhance Raman signals. Coupled with Density functional theory, sulfadiazine characteristic peaks 877 cm-1 and 994 cm-1, sulfamethazine characteristic peak 661 cm-1, sulfathiazole characteristic peaks 862 cm-1 and 1127 cm-1 were found and used to qualitatively and quantitatively analyze antibiotics residues in swine urine. The minimum detection amounts of sulfadiazine, sulfamethazine and sulfathiazole in swine urine were 0.1, 0.1 and 0.2 mg/L, respectively. And TLC can achieve the separation of mixed antibiotics in swine urine. The characteristic peaks of each antibiotic are easily distinguished when the concentration of three mixed antibiotics in swine urine was 0.01 μg. TLC-SERS technology showed to be suitable for rapid detection of antibiotic residues in pig urine.

江西省博士后科研项目资助（2015KY21）