A Localized Surface Plasmon Resonance Biosensor Based on Integrated Controllable Au2S/AuAgS-Coated Gold Nanorods Composite
In this work, we have demonstrated that the exquisite optical properties based on localized surface plasmon resonance (LSPR) of Au2S/AuAgS-coated gold nanorods (Au2S/AuAgS-coated GNRs) can be utilized to develop a simple and sensitive biosensor, and goat anti-human IgG can be detected by the human IgG probe as low as 0.2 nM. Moreover, we introduce an integrated LSPR biosensor constructed by integrating Au2S/AuAgS-coated GNRs immobilized on glass slide and isolated Au2S/AuAgS-coated GNRs in the form of liquid. The detection of target binding was performed via direct spectral changes induced by changes of refractive index in the vicinity of individual particles. The integrated LSPR optical biosensor is label-free, cost-effective, and easy to fabricate and requires only a visible/near-infrared spectrometer for detection purposes. Additionally, the investigation on the mutual influence of the two types of nanorods in the integrated LSPR biosensor was performed. The results of separate experiments indicate that the nanorods in the form of isolate or in integrated exhibit a similar behavior.
KeywordsLocalized surface plasmon resonance Au2S/AuAgS-coated gold nanorods Integrated LSPR biosensor