Combination of Porous Silk Fibroin Substrate and Gold Nanocracks as a Novel SERS Platform for a High-Sensitivity Biosensor.

Ji Hyeon Choi,Tien Son Ho,Seung Ho Choi,Taeyoung Kang,Kyung Min Byun,Munsik Choi

doi:10.3390/bios11110441

Abstract

Novel concepts for developing a surface-enhanced Raman scattering (SERS) sensor based on biocompatible materials offer great potential in versatile applications, including wearable and in vivo monitoring of target analytes. Here, we report a highly sensitive SERS sensor consisting of a biocompatible silk fibroin substrate with a high porosity and gold nanocracks. Our silk-based SERS detection takes advantage of strong local field enhancement in the nanoscale crack regions induced by gold nanostructures evaporated on a porous silk substrate. The SERS performance of the proposed sensor is evaluated in terms of detection limit, sensitivity, and linearity. Compared to the performance of a counterpart SERS sensor with a thin gold film, SERS results using 4-ABT analytes present that a significant improvement in the detection limit and sensitivity by more than 4 times, and a good linearity and a wide dynamic range is achieved. More interestingly, overlap is integral, and a quantitative measure of the local field enhancement is highly consistent with the experimental SERS enhancement.

Highlights

Surface-enhanced Raman scattering (SERS) has been widely employed as a spectroscopic technique for the identification of chemical and biological species due to its advantages of high sensitivity, unique spectroscopic fingerprints, and non-destructive detection [1,2,3]
The principal amplification of SERS arises from an enhancement of local electromagnetic fields near or at a nanostructured metallic substrate, which is associated with the resonant excitation of localized surface plasmons [4,5]
Conjugated polymers (CPs) as organic macromolecules can combine the high conductivity of metals with the chemical tunability of polymers

Summary

Introduction

Surface-enhanced Raman scattering (SERS) has been widely employed as a spectroscopic technique for the identification of chemical and biological species due to its advantages of high sensitivity, unique spectroscopic fingerprints, and non-destructive detection [1,2,3].

Results

Conclusion