Bioinspired Material-Integrated Sensors for Improving Nanoplasmonic Characteristics

Abstract

In this study, we developed a nanoplasmonic-based sensor design, which was constructed with a bio-inspired silk material and plasmonic materials (gold nanoparticles). We characterized this mutual integration at molecular level by using Atomic Force Microscopy, Scanning Electron Microscopy, as well as the chemical composition was confirmed with Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy and X-Ray Photoelectron Spectroscopy analyses, along with contact angle measurements for hydrophilicity/hydrophobicity evaluation. Once a single layer of silk-gold nanoparticle mixture was accomplished, we serially applied an adlayer and plasmonic material to create more sensitive surface. Accordingly, we benchmarked the performance of the multi-layer sensor system, and observed ~6.8 times (or red-shifts from 7.93 nm to 12.90 nm) signal improvements compared to the one developed by a single layer. In sum, we here presented (i) a facile drop-casting method for developing a nanoplasmonic sensor design, (ii) the use of inexpensive off-the-shelf plastic as a substrate, (iii) easy-to-adapt strategy with standard spectrometer devices, and (iv) minimum training for its proper use.