Agricultural Product Processing and Storage Lab, School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu, 212013, China.
Agricultural Product Processing and Storage Lab, School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu, 212013, China.
Biosens Bioelectron. 2019 Dec 1;145:111672. doi: 10.1016/j.bios.2019.111672. Epub 2019 Sep 3.
Currently, the detection of pesticide is critical for food safety assurance, but it is still challenging due to the presence of biological interferents from complex food matrix. In this study, we developed an optical anti-interference surface-enhanced Raman scattering (SERS) aptasensor system for trace detection of acetamiprid. 4-(Mercaptomethyl) benzonitrile (MMBN) containing CN bond was used as Raman tag to provide a sharp peak (2227 cm) in the Raman-silent spectral window (1800-2800 cm) where no Raman signal existed for most of molecules. Gold nanoparticles (AuNPs) bonded with polyadenine (polyA)-mediated aptamer and Raman tag (MMBN-AuNPs-aptamer) was synthesized as Raman probe, while the complementary DNA (cDNA) conjugated with AgNPs-decorated silicon wafer (AgNPs@Si) was used as SERS substrate. As acetamiprid molecule could specifically combine with aptamer, preventing the formation of MMBN-AuNPs-aptamer-cDNA-AgNPs@Si (expressed as "Au-AgNPs@Si") hybrid through DNA sequence linking, Raman signal intensities of MMBN in Au-AgNPs@Si decreased when the concentration of acetamiprid increased. Under the optimum assay condition, the proposed method displayed a linear response for acetamiprid detection in the range of 25-250 nM with a low detection limit of 6.8 nM. Finally, the developed aptasensor was successfully used to determine acetamiprid content in apple juice. Accordingly, this novel anti-interference SERS aptasensor could be a promising acetamiprid sensor for food safety assurance.
目前，农药检测对于食品安全保障至关重要，但由于复杂食品基质中存在生物干扰物，检测仍然具有挑战性。在本研究中，我们开发了一种光学抗干扰表面增强拉曼散射（SERS）适体传感器系统，用于痕量检测乙虫腈。含 CN 键的 4-（巯基甲基）苯甲腈（MMBN）被用作拉曼标记物，在拉曼沉默光谱窗口（1800-2800 cm）中提供尖锐的峰（2227 cm），其中大多数分子没有拉曼信号。金纳米粒子（AuNPs）与多聚腺嘌呤（polyA）介导的适体和拉曼标记物（MMBN-AuNPs-aptamer）结合作为拉曼探针，而互补 DNA（cDNA）与 AgNPs 修饰的硅片（AgNPs@Si）偶联作为 SERS 基底。由于乙虫腈分子可以特异性地与适体结合，通过 DNA 序列连接阻止 MMBN-AuNPs-aptamer-cDNA-AgNPs@Si（表示为“Au-AgNPs@Si”）杂交的形成，当乙虫腈浓度增加时，Au-AgNPs@Si 中 MMBN 的拉曼信号强度降低。在最佳测定条件下，该方法对乙虫腈的检测范围为 25-250 nM，检测限低至 6.8 nM。最后，该开发的适体传感器成功地用于测定苹果汁中的乙虫腈含量。因此，这种新型抗干扰 SERS 适体传感器有望成为食品安全保障的乙虫腈传感器。
