用于快速检测沙丁胺醇的分子印迹传感器的制备及其在食品检测中的应用

Preparation of Molecular Imprinting Electro-biosensor for the Rapid Detection of Salbutamol and Its Application in Food

首先通过电沉积纳米金,电聚合聚硫堇对玻碳电极表面进行了修饰,之后利用沙丁胺醇为模板分子,通过电聚合α-甲基丙烯酸,制备了一种选择性具有特异识别功能的纳米金/聚硫堇/沙丁胺醇分子印迹电化学传感器。实验采用循环伏安法和差分脉冲法,对不同的修饰电极进行了表征,优化电极的制备和测定条件,研究了印迹传感器对模板分子的选择性响应。结果表明:最佳制备条件下,模板分子:功能单体=1:4,聚合15圈,以0.5 mmol/L硫酸:乙腈(1:9,V/V)洗脱10 min,在pH=7.0的PBS溶液中进行DPV检测,线性范围为2.0×10^(-7)~1.0×10^(-4) mol/L,检测限为6.0×10^(-8) mol/L,S/N=3。该传感器灵敏度高,抗干扰能力强,重现和稳定性好。利用制备的分子印迹电化学传感器对食品中的沙丁胺醇进行了测定,回收率在86.5%~111.9%(n=3),结果令人满意。

A glass electrode was initially modified by electrodeposition of nanogold and polymerization of polythionine.Then,using salbutamol as a molecular template,a nano-Au/polythionine/salbutamol molecular imprinting electro-biosensor,with specific recognition capability,was prepared by electropolymerization of α-methacrylic acid（MAA） on the surface.Cyclic voltammetry（CV） and differential pulse voltammetry（DPV） were employed to characterize the different modified electrodes;preparation of the modified electrodes and the detection conditions were optimized,and the selectivity responses of the biosensor towards the template molecule were investigated.The results showed that under the optimum condition,the ratio of molecular template to functional monomer was 1：4;15 polymerization cycles were carried out,and 0.5 mmol/L sulfuric acid and acetonitrile=1：9（V/V） was used to elute for 10 min.The DPV measurement was conducted at pH 7.0 in phosphate-buffered saline（PBS） solution,the linear range was 2.0×10-（-7）-1.0×10-（-4） mol/L,and the detection limit was 6.0×10-（-8） mol/L（S/N=3）.The sensor has good sensitivity,strong anti-interference ability,and good reproducibility and stability.The prepared biosensor was applied in the detection of salbutamol in food with a recovery of 86.5%-111.9%（n=3）,and the results were satisfactory.