Gold Nanoparticles Modified a Multimode Clad-Free Fiber for Ultrasensitive Detection of Bovine Serum Albumin

Abstract

Gold nanoparticles (Au NPs) were almost chosen as the first option for biological and biosensor applications due to their enhancement and their outstanding properties. The combining of optical fiber with localized surface plasmon resonance (LSPR) for forming a biosensor is widely used in diagnosis. In this work, we report a fiber optical biosensor based on LSPR of Au NPs for the detection of bovine serum albumin (BSA) protein. BSA was functionalized on Au NPs immobilized fiber optic sensing head (length of 1 cm) via methanesulfonic acid (MSA) by carboxylic binding. It is the binding between the analytes with the surface-modified Au NPs that caused refractive index changes in the sensing medium led to changes in optical power at the output of the sensor. The detection limit of the LSPR fiber biosensor was found to be 0.18 ng/mL for the BSA detection with the low coefficient of variation (CV) at under 1%. We have demonstrated the effectiveness of combining multimode fiber with Au NPs to generate the biosensor as the label-free sensor that can be a feasible tool for highly sensitive, rapid response time, stable, and miniaturized point-of-care analytical systems.

Gold and Silver Nanoparticle-Based Colorimetric Sensors: New Trends and Applications

“…When the BSA reaches the sensing zone, the refractive index (RI) changes. The intensity of transmitted light increases as the concentration of BSA in the solution increases [154].…”

Review of Fiber-Optic Localized Surface Plasmon Resonance Sensors: Geometries, Fabrication Technologies, and Bio-Applications

“…Amine silanization is based on the principle of positive and negative adsorption effects. It entails the use of solutions like (3-aminopropyl) triethoxysilane [62] (APTES) or (3-aminopropyl) trimethoxysilane [63] (APTMS) to aminofunctionalize the surface of the optical fiber through an amination reaction, thus imparting a positive charge. Consequently, the negatively charged nanoparticles can be bound to the positively charged optical fiber surface through electrostatic forces, particularly the interaction of ionic bonds.…”

Synthesis, characterization, and applications of gold nanoparticles in development of plasmonic optical fiber-based sensors

“…By establishing a local dielectric environment on the AuNPs, LSPR increases thereby enhancing the sensitivity [24]. Much research has reported LSPR based sensors for detection of biomolecules which are important biomarkers in detection of diseases [25,26]. The sensor performance is highly dependent on the materials, structure, and target analyte.…”