Fabrication of Localized Surface Plasmon Resonance Fiber Probes Using Ionic Self-Assembled Gold Nanoparticles

Miao Wan,Zhiyong Wang,Pengfei Luo,Stephen T C Wong,Jiayi Jin,Jiong Xing

doi:10.3390/s100706477

Abstract

An nm-thickness composite gold thin film consisting of gold nanoparticles and polyelectrolytes is fabricated through ionic self-assembled multilayers (ISAM) technique and is deposited on end-faces of optical fibers to construct localized surface plasmon resonance (LSPR) fiber probes. We demonstrate that the LSPR spectrum induced by ISAM gold films can be fine-tuned through the ISAM procedure. We investigate variations of reflection spectra of the probe with respect to the layer-by-layer adsorption of ISAMs onto end-faces of fibers, and study the spectral variation mechanism. Finally, we demonstrated using this fiber probe to detect the biotin-streptavidin bioconjugate pair. ISAM adsorbed on optical fibers potentially provides a simple, fast, robust, and low-cost, platform for LSPR biosensing applications.

Highlights

Localized surface plasmon resonance (LSPR) is the resonance phenomenon of surface plasmons in the metal [1,2]
We demonstrate that the LSPR spectrum induced by the ionic self-assembled multilayers (ISAM) based gold thin film can be fine-tuned through the ISAM procedure
An optical fiber was used as a substrate, citrate-anion coated colloid AuNPs were used as the polyanion while poly(allylamine hydrochloride) (PAH) at pH = 4.3 was used as the polycation

Summary

Introduction

Localized surface plasmon resonance (LSPR) is the resonance phenomenon of surface plasmons in the metal [1,2]. It occurs when light interacts with particles much smaller than the incident wavelength. ISAM based gold films adsorbed on optical fibers can potentially provide a fast, cost effective, robust platform for building efficient LSPR sensors. AuNPs and polyelectrolytes is fabricated through ISAM technique and was deposited on end-faces of multimode optical fibers to construct LSPR fiber probes. ISAM adsorbed on optical fibers potentially provides a simple, fast, robust, and low-cost, platform for LSPR biosensing applications

Materials and Methods

AFM Images of ISAM Gold Films on Fiber End-Face

Simulations of ISAM Films on Fiber End-Face

Biotin-Streptavidin Immunobiosensors

Conclusions