A molecularly imprinted photonic crystal-based sensor for the rapid detection of oxytetracycline residues in milk
摘要
以土霉素(OTC)分子为模板分子,光子晶体为基质材料,成功构建了基于光子晶体的分子印迹膜(MIM@PCs),并用于牛奶样品中土霉素残留的快速检测.构建的MIM@PCs可以选择性捕获样品中的OTC分子,目标分子的结合会引起MIM@PCs结构的有序性变化,导致MIM@PCs结构色改变或特征峰位移,从而将目标分子识别过程转换为光学信号分析,实现样品中OTC分子的高灵敏、高选择性检测.最佳条件下,制备的分子印迹光子晶体传感器对样品中OTC的响应时间为3 min.当OTC浓度在1.9～10.0 µg/L范围内时,MIMs的特征峰位移量与OTC的浓度线性相关(R2=0.9967),OTC检出限为1.9 µg/L.制备的MIM@PCs对OTC分子具有选择性,对结构类似物无明显响应.将MIM@PCs应用于牛奶样品中OTC残留检测,加标回收率为97.5%～102.8%,相对标准偏差为2.3%～4.7%.该方法能够满足实际样品中OTC残留的检测需求.
A molecularly imprinted photonic membrane(MIM@PCs)was constructed for the rapid detection of oxytetracycline(OTC)residues in milk samples by using OTC as the template molecule and photonic crystals as the substrate material.The prepared MIM@PCs can specifically capture OTC molecules in the sample.The binding of target molecules changes the structure of the MIM@PCs,resulting in changes in the structural color or characteristic peak shifts of the MIM@PCs.This transforms the target molecule recognition process into optical signal analysis,enabling rapid detection of OTC molecules in samples.Under optimal conditions,the photonic crystal-based molecularly imprinted sensor exhibited a response time of 3 min for OTC in the sample.When the OTC concentration ranged from 1.9 to 10.0 µg/L,the characteristic peak shift of the photonic crystal molecularly imprinted membrane showed a linear correlation with the OTC concentration(R2=0.9967),with a detection limit of 1.9 µg/L.The prepared MIM@OTC showed no significant response to structural analogs of OTC,indicating its selectivity for OTC molecules.When MIM@PCs were used to determine OTC in milk samples,the spiked recovery rates of OTC ranged from 97.5%to 102.8%,with the relative standard deviations(RSDs)between 2.3%and 4.7%.This method can achieve rapid determination of OTC residues in milk samples.
