Waitkus Jacob, Chang Yu, Liu Li, Puttaswamy Srinivasu Valagerahally, Chung Taerin, Vargas Adrian M Molina, Dollery Stephen J, O'Connell Mitchell R, Cai Haogang, Tobin Gregory J, Bhalla Nikhil, Du Ke
University of California, Riverside, Riverside, CA, USA.
NIBEC School of Engineering, Ulster University, Belfast, UK.
Adv Mater Interfaces. 2023 Jan 5;10(1). doi: 10.1002/admi.202201261. Epub 2022 Nov 27.
A novel localized surface plasmon resonance (LSPR) system based on the coupling of gold nanomushrooms (AuNMs) and gold nanoparticles (AuNPs) is developed to enable a significant plasmonic resonant shift. The AuNP size, surface chemistry, and concentration are characterized to maximize the LSPR effect. A 31 nm redshift is achieved when the AuNMs are saturated by the AuNPs. This giant redshift also increases the full width of the spectrum and is explained by the 3D finite-difference time-domain (FDTD) calculation. In addition, this LSPR substrate is packaged in a microfluidic cell and integrated with a CRISPR-Cas13a RNA detection assay for the detection of the SARS-CoV-2 RNA targets. Once activated by the target, the AuNPs are cleaved from linker probes and randomly deposited on the AuNM substrate, demonstrating a large redshift. The novel LSPR chip using AuNP as an indicator is simple, specific, isothermal, and label-free; and thus, provides a new opportunity to achieve the next generation multiplexing and sensitive molecular diagnostic system.
一种基于金纳米蘑菇（AuNMs）与金纳米颗粒（AuNPs）耦合的新型局域表面等离子体共振（LSPR）系统被开发出来，以实现显著的等离子体共振位移。对AuNP的尺寸、表面化学性质和浓度进行了表征，以使LSPR效应最大化。当AuNMs被AuNPs饱和时，实现了31 nm的红移。这种巨大的红移还增加了光谱的半高宽，并通过三维时域有限差分（FDTD）计算得到了解释。此外，这种LSPR基底被封装在微流控芯片中，并与用于检测SARS-CoV-2 RNA靶点的CRISPR-Cas13a RNA检测分析相结合。一旦被靶点激活，AuNPs就会从连接探针上裂解下来，并随机沉积在AuNM基底上，呈现出较大的红移。使用AuNP作为指示剂的新型LSPR芯片简单、特异、等温且无需标记；因此，为实现下一代多重和灵敏的分子诊断系统提供了新的机会。
