Center for Molecular Recognition and Biosensing, School of Life Sciences, Shanghai University, Shanghai 200444, PR China; Shanghai Key Laboratory of Bio-Energy Crop, School of Life Sciences, Shanghai University, Shanghai 200444, PR China.
Center for Molecular Recognition and Biosensing, School of Life Sciences, Shanghai University, Shanghai 200444, PR China.
Biosens Bioelectron. 2018 Oct 15;117:605-612. doi: 10.1016/j.bios.2018.06.057. Epub 2018 Jun 28.
Paraquat (PQ) residue is harmful for people's health. This work fabricated an efficient approach to determine PQ sensitively. We exploited a novel surface plasmon resonance (SPR) detection system based on the analyte induced network architecture of supermolecules modified gold nanoparticles (AuNPs) on the chip surface. para-Sulfonatocalix[4]arene (pSC) were used as a recognition molecule for paraquat. PQ can mediate the aggregation of pSC capped AuNPs (pSC-AuNPs) through the host-guest recognition, which can be used as signal amplification for PQ assay. This achievement is due to several outstanding properties of this detection system: first, local SPR and high refractive index of AuNPs can enhance the signal of SPR dramatically; second, AuNPs is more stable and biocompatible and diffusely used in colorimetric methods; third, the network AuNPs structure has unique photo characterization for enhancement of SPR. Analyte induced AuNPs aggregation amplified SPR assay shows dramatic signal enhancement ability. The detection limit for PQ was found to be 2.2 pM This strategy provides a new concept for developing sensitive SPR sensors for the highly selective detection of small molecules.
百草枯（PQ）残留对人体健康有害。本工作构建了一种灵敏测定百草枯的有效方法。我们利用基于表面等离子体共振（SPR）检测系统，通过在芯片表面修饰超分子的分析物诱导网络结构，实现了对金纳米粒子（AuNPs）的有效检测。对磺化杯[4]芳烃（pSC）被用作百草枯的识别分子。PQ 可以通过主客体识别介导 pSC 封端的 AuNPs（pSC-AuNPs）的聚集，这可以作为 PQ 分析的信号放大。这一成果归因于该检测系统的几个突出特性：首先，局部 SPR 和 AuNPs 的高折射率可以显著增强 SPR 的信号；其次，AuNPs 更稳定、生物相容性更好，并广泛应用于比色法；第三，网络 AuNPs 结构具有独特的光特性，可增强 SPR。分析物诱导的 AuNPs 聚集放大 SPR 分析显示出显著的信号增强能力。发现 PQ 的检测限为 2.2 pM。该策略为开发用于小分子高选择性检测的灵敏 SPR 传感器提供了新的概念。
