摘要
试验吡咯为功能单体,草甘膦为模板,在金电极表面通过电聚合制备了一种具有良好草甘膦印迹能力的新型分子印迹电化学电极。以铁氰化钾为活性探针,优化了模板分子与功能单体配比、扫描圈数、检测体系pH值和吸附时间等关键参数,构建了快速检测草甘膦残留的电化学方法。结果表明,该电极对草甘膦具有响应快、灵敏度高和稳定性好的优点,电极的响应电流与草甘膦浓度(5~500 ng/mL的范围)内呈良好的线性关系(r^(2)=0.985),定性检出限为0.5 ng/mL。该电极对草甘膦分子具有较好的选择性和精密性,样品回收率为101%~106%,相对标准偏差为2.89%。同一根电极在初次使用后的第7、14、21、28天测量时,印迹电极的响应值降至初始响应值的90.4%、87.8%、80.4%、75.7%,总体表明印迹电极的稳定性良好。
A novel molecularly imprinted electrochemical senor with good imprinted capacity to glyphosate was prepared by electropolymerisation on the gold electrode surface,with pyrrole as functional monomer,glyphosate as template.Using potassium ferricyanide as the active probe,the key parameters such as the ratio of template molecule to functional monomer,the number of scanning cycles,pH value of detection system and adsorption time were optimized to construct a rapid electrochemical method for the detection of glyphosate residues.The results showed that the sensor had the advantages of fast response,high sensitivity and good stability to glyphosate in the optimal detection system.There was a good linear relationship between the peak current of the sensor and glyphosate concentration in the range of 5~500 ng/mL,the correlation coefficient was 0.985,and the qualitative detection limit was 0.5 ng/mL.The sensor had good selectivity and precision for glyphosate molecules,the sample recovery was 101%~106%,the relative standard deviation was 2.89%.On the 7th,14th,21st,and 28th day after the first use of the same sensor,the response value of the imprinted electrode decreased to 90.4%,87.8%,80.4%,and 75.7%of the initial response value,indicating that the stability of the imprinted electrode was good.
作者
练惠琳
李雨欣
周圆圆
田雯欣
许祯毅
LIAN Hui-lin;LI Yu-xin;ZHOU Yuan-yuan;TIAN Wen-xin;XU Zhen-yi(College of Tea and Food Science,Wuyi University,Fujian Wuyishan 354300,China)
出处
《广州化工》
CAS
2023年第19期20-22,共3页
GuangZhou Chemical Industry
基金
大学生创新创业训练计划项目(S202010397031)
福建省中青年教师教育科研项目(JAT190793)。
关键词
吡咯
草甘膦
分子印迹
电化学电极
pyrrole
glyphosate
molecular imprinting
electrochemical sensor