Yang Zhanye, Zhang Nan, Lv Haiyang, Ju Xinge, Chen Yanhua, Zhang Ziwei, Tian Yuan, Zhao Bing
College of Chemistry, Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments, Jilin University, Changchun, 130012, People's Republic of China.
State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun, 130012, People's Republic of China.
Mikrochim Acta. 2024 Dec 24;192(1):29. doi: 10.1007/s00604-024-06897-x.
A highly sensitive aptamer sensor (aptasensor) is proposed based on metal-organic frameworks-silver nanoparticles (AgNPs@MOF) to detect sulfadimethoxine (SDM) by surface-enhanced Raman spectroscopy (SERS). AgNPs@MOF with SERS activity was successfully fabricated by synthesizing AgNPs in situ on the surface of MIL-101(Fe), and SDM aptamer and Raman reporter 4-aminophenthiophenol (4-ATP) were selected as specific recognition elements and signal probes, respectively. When SDM was absent, the SDM aptamers were effectively adsorbed on the surface of AgNPs@MOF, thus keeping AgNPs@MOF in a dispersed state, resulting in a weakened SERS signal of 4-ATP. In the presence of SDM, the combination of SDM and aptamer formed a rigid hairpin SDM-aptamer complex, which bound less to AgNPs@MOF. Therefore, fewer aptamers were adsorbed on AgNPs@MOF, which exposed more hot spots, resulting in an enhanced SERS signal of 4-ATP. The aptasensor had good selectivity and sensitivity towards SDM and a good linear relationship between SERS intensity and SDM concentration in the range 6.00-150.00 ng/mL, with the limit of detection as low as 2.73 ng/mL. Further application to honey and chicken samples spiked with SDM resulted in satisfactory recoveries, and the aptasensor showed good stability and reproducibility in real samples. The aptasensor based on AgNPs@MOF was proposed for the first time to detect trace SDM by SERS, which provided a favorable way to develop various sensing platforms for antibiotic detection in food safety.
基于金属有机框架-银纳米颗粒（AgNPs@MOF）构建了一种高灵敏度适配体传感器（aptasensor），用于通过表面增强拉曼光谱（SERS）检测磺胺二甲氧嘧啶（SDM）。通过在MIL-101(Fe)表面原位合成AgNPs成功制备了具有SERS活性的AgNPs@MOF，并分别选择SDM适配体和拉曼报告分子4-氨基苯硫酚（4-ATP）作为特异性识别元件和信号探针。当不存在SDM时，SDM适配体有效地吸附在AgNPs@MOF表面，从而使AgNPs@MOF保持分散状态，导致4-ATP的SERS信号减弱。在存在SDM的情况下，SDM与适配体结合形成刚性发夹状SDM-适配体复合物，该复合物与AgNPs@MOF的结合较少。因此，吸附在AgNPs@MOF上的适配体较少，暴露出更多的热点，导致4-ATP的SERS信号增强。该适配体传感器对SDM具有良好的选择性和灵敏度，在6.00-150.00 ng/mL范围内SERS强度与SDM浓度之间具有良好的线性关系，检测限低至2.73 ng/mL。对添加了SDM的蜂蜜和鸡肉样品的进一步应用获得了令人满意的回收率，并且该适配体传感器在实际样品中显示出良好的稳定性和重现性。首次提出基于AgNPs@MOF的适配体传感器通过SERS检测痕量SDM，这为开发用于食品安全中抗生素检测的各种传感平台提供了一种有利的方法。
