新型硅线阵列多功能芯片构建及其在细菌捕获、拉曼检测与抗菌上的应用

Despite the advancements in bacterial capture, detection and antibacterial techniques, the development of novel platform with multiple abilities, capable of capture, detection and inactivation of tiny bacteria remains a significant challenge. In this project, silicon nanowire array (SiNWAr) -based multifunctional chip is fabricated for capturing, Raman discriminating and inactivating bacteria. The developed chip is made of bacteria-binding molecules-modified and gold nanoparticles (Au NPs)-decorated SiNWAr (AuNPs@SiNWAr). Significantly, the fabricated chip features three dominant merits: (1) good bacterial capture efficiency owing to the synergistic effect of the nanotopography and surface chemistry of the SiNWAr; (2) excellent reproducibility due to the immobilization of AuNPs on the surface of chip, and low detection limit ascribed to strong Raman signals; (3) as well as high antibacterial activity because of excellent photothermal effect of AuNPs@SiNWAr. The as-prepared SERS chip could be served as a novel tool for the diagnosis and inactivation of pathogenic bacteria in clinical or environmental samples.

尽管细菌捕获、检测和抗菌技术有了长足的进展，获得同时具备高效捕获细菌，快速、灵敏诊断细菌以及有效抗菌能力的分析平台却依然是个严峻的挑战。本项目拟构建基于硅线阵列的新型多功能芯片同时实现细菌有效捕获、拉曼检测和抗菌。该芯片由金纳米颗粒修饰的硅纳米线阵列构成，进一步在金纳米颗粒表面修饰上细菌连接分子：4-巯基苯硼酸或万古霉素。该芯片具有如下特点：（1）芯片表面修饰上的细菌连接分子及硅线的纳米形貌可以协同促进细菌捕获；（2）金纳米颗粒固定在硅纳米线表面可以获得重现性好且较强的拉曼信号，极大提高细菌检测准确度和灵敏度；（3）构建的芯片具有较强的光热作用可以有效杀死细菌。该芯片将为细菌感染的早期诊断与治疗提供新工具与新方法。

为了同时实现高效捕获细菌，快速、灵敏诊断细菌以及有效抗菌，在本项目的支持下，我们构建了一系列硅基纳米杂化SERS基底，包括：（1）金纳米颗粒修饰的硅纳米线阵列（AuNPs@SiNWsAr）; (2)石墨烯-银纳米颗粒-硅基三明治结构的SERS基底(G@AgNPs@Si) ，进一步在基底表面修饰上细菌连接分子（如万古霉素等），从而构建出新型硅基多功能芯片。特别地，AuNPs@SiNWsAr的硅线的纳米形貌有利于细菌的捕获，根据细菌的拉曼特征指纹峰实现对其鉴定，此外它具有较优异的光热性能,能够用于有效的光热抗菌；G@AgNPs@Si修饰的万古霉素可以用来捕获细菌，也可以抑制细菌的生长，此外位于拉曼沉默区的石墨烯特征峰(2D)可以作为内标校准SERS信号。 上述结果表明，我们构建出的硅基多功能芯片可以同时实现细菌有效捕获、拉曼检测和抗菌。