Fiber Surface Modification Technology for Fiber-Optic Localized Surface Plasmon Resonance Biosensors

Abstract

Considerable studies have been performed on the development of optical fiber sensors modified by gold nanoparticles based on the localized surface plasmon resonance (LSPR) technique. The current paper presents a new approach in fiber surface modification technology for biosensors. Star-shaped gold nanoparticles obtained through the seed-mediated solution growth method were found to self-assemble on the surface of tapered optical fibers via amino- and mercapto-silane coupling agents. Transmitted power spectra of 3-aminopropyltrimethoxy silane (APTMS)-modified fiber were obtained, which can verify that the silane coupling agent surface modification method is successful. Transmission spectra are characterized in different concentrations of ethanol and gentian violet solutions to validate the sensitivity of the modified fiber. Assembly using star-shaped gold nanoparticles and amino/mercapto silane coupling agent are analyzed and compared. The transmission spectra of the gold nanoparticles show that the nanoparticles are sensitive to the dielectric properties of the surrounding medium. After the fibers are treated in t -dodecylmercaptan to obtain their transmission spectra, APTMS-modified fiber becomes less sensitive to different media, except that modified by 3-mercaptopropyltrimethoxy silane (MPTMS). Experimental results of the transmission spectra show that the surface modified by the gold nanoparticles using MPTMS is firmer compared to that obtained using APTMS.

Diverse Applications of Electronic-Nose Technologies in Agriculture and Forestry

“…Thus, optical biosensors compliment the same detection objectives of e-nose instruments. Zhang et al [353] recently proposed a new fiber surface-modification methodology using gold nanoparticles to increase the sensitivity of fiber-optic plasmon resonance biosensors.…”

Thermal annealing of gold coated fiber optic surfaces for improved plasmonic biosensing

“…Many of these methods rely on improving the quality and/or optimizing the morphology of the thin gold (Au) film sputtered on the FO silica core within the sensitive zone, with a reported thickness around 50 nm for an optimal SPR excitation [10]. One way is to simply use an organosilane compound, such as (3-aminopropyl)trimethoxysilane (APTMS) [11] or (3-mercaptopropyl)trimethoxysilane (MPTMS) [12], as an efficient adhesion promoter for the Au layer attachment to the FO. Such protocols allow the design of FO-SPR sensors with considerably improved chemical stability and mechanical robustness [12], while mainly not affecting other performance quantifiers of the device, such as sensitivity or limit of detection (LOD).…”

“…spheres, rods, triangles) possessing great plasmonic properties. In most of the cases, FO surfaces functionalized with amino-or thiol-groups attract the nanomaterials via either covalent or electrostatic linkage strategies [11], [21]. However, these protocols are not always easy to implement due to the potential limitations in polydispersity and reproducibility, mainly associated with the nanomaterials aggregation during the process [22].…”

Novel Highly Sensitive Protein Sensors Based on Tapered Optical Fibres Modified with Au-Based Nanocoatings

“…Recently, the use of tapered optical fibres modified with Au nanoparticles to create sensors based on the surface plasmon resonance (SPR) phenomenon attracted a lot of attention [22,23]. Zhang et al reported the development of a tapered optical fibre biosensor based on Au nanoparticles to create localized surface plasmon resonances (LSPR) [24]. A salinization method using 3-aminopropyltrimethoxy silane (APTMS) and 3-mercaptopropyltrimethoxy silane (MPTMS) was employed for the deposition of the star-shaped Au nanoparticles onto the surface of a tapered optical fibre.…”