利用磁固相萃取和表面增强拉曼光谱定量检测鸡肉和猪肉中的恩诺沙星

Quantitative detection of enrofloxacin in chicken and pork by magnetic solid phase extraction and surface-enhanced Raman spectroscopy

目的利用磁性固相萃取(MSPE)结合表面增强拉曼光谱(SERS)建立一种鸡肉和猪肉中恩诺沙星的快速定量检测方法。方法合成Fe3O4@共价有机骨架纳米复合材料,并将其作为吸附剂分离和富集恩诺沙星。以银纳米颗粒为增强基底,利用便携式拉曼光谱仪采集恩诺沙星的SERS光谱。利用恩诺沙星的特征SERS信号进行定量分析。结果恩诺沙星位于745.77 cm^(-1)拉曼位移处的SERS信号强度与其浓度的对数值在5.0×10^(-7)~1.0×10^(-5)mol/L范围内呈现出良好的线性关系,决定系数R^(2)为0.962。检出限和定量限分别为0.07和0.23μg/g。该方法检测鸡肉和猪肉中恩诺沙星的回收率为80.97%~100.98%,相对标准偏差为1.6%~4.6%。结论MSPE-SERS方法操作简便、用时短、灵敏度高、稳定性好,为恩诺沙星的快速检测和现场检测提供了一种新方法。

Objective To develop a rapid and quantitative method for the detection of enrofloxacin in chicken and pork using magnetic solid phase extraction(MSPE)combined with surface enhanced Raman spectroscopy(SERS).Methods Magnetic Fe3O4@covalent organic framework(COF)nanocomposites were synthesized and applied as absorbent to separate and enrich enrofloxacin.The SERS spectra of enrofloxacin were collected by a portable Raman spectrometer with Ag nanoparticles as enhancing substrate.The characteristic SERS signals of enrofloxacin were used to realize its quantification.Results Intensities of SERS signals at 745.77 cm^(-1) and the logarithmic values of the concentrations of enrofloxacin in the range of 5.0×10^(-7) to 1.0×10^(-5) mol/L displayed a good linear relationship with a coefficient of determination of 0.962.The limit of detection and limit of quantitation were 0.07 and 0.23µg/g respectively.The recoveries of enrofloxacin in chicken and pork were 80.97%~100.98%with relative standard deviations of 1.6%~4.6%.Conclusion The developed method has the advantages of simple in operate,short in time,high in sensitivity and stability,which provides a new method for the rapid detection and on-site detection of enrofloxacin.