Simple Preparation of Au Nanoparticle Dispersed Substrate by Arc Plasma Deposition and Its Application in Bio-Sensing using LSPR

Abstract

We propose a simple preparation of a Localized Surface Plasmon Resonance (LSPR) device in which Au nanoparticles (AuNPs) are dispersed on SiO₂/Si substrates using arc plasma deposition (APD). APD can coat AuNPs directly onto a substrate using a single-step process with a very short deposition time. The dispersion and diameter of the AuNPs were evaluated based on the APD characteristics: applied voltage (V), capacitance (C), and number of pulses (n). The LSPR device was prepared under the best conditions for reflectance spectra: C=2200 μF, V=100 V, n=80, and vacuum condition of 1.3 × 10⁻³ Pa at room temperature, and protein−protein interactions (PPIs) were detected using the device. The fabricated device could detect avidin over a wide range from 1 ng/mL to 10 µg/mL. The detection limit was 0.33 ng/mL, which is considerably low compared to that of other detection methods. These results demonstrate that APD is useful for fabricating superior nanoparticles without additional processes such as photolithography and etching.