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.
Highlights
Gold nanoparticles (Au NPs) with unique properties such as excellent compatibility, intense light scattering/absorption, high surface area to volume ratios, highly selective interoperability through electrostatic interaction, stable structure, and nontoxic have become the first choice among plasmonic nanoparticles for biological and biosensor applications [1,2,3]
The use of the intermediate particle development method helps to control the properties of the gold nanoparticles such as absorption size and wavelength, in addition to helping to produce single dispersed Au NPs
The Au NPs formation with localized surface plasmon resonance (LSPR) of 524.5 nm and the color of solution (Figure 3) implied the appearance of the spherical Au NPs, which is directed in this experiment due to the usefulness of them in bioapplications [14]
Summary
Gold nanoparticles (Au NPs) with unique properties such as excellent compatibility, intense light scattering/absorption, high surface area to volume ratios, highly selective interoperability through electrostatic interaction, stable structure, and nontoxic have become the first choice among plasmonic nanoparticles for biological and biosensor applications [1,2,3]. Au NPs have a special phenome that is localized surface plasmon resonance (LSPR), which was widely studied recently in sensing platforms due to its great advantages [4,5,6]. It provides compact, label-free, highly sensitive, and stable biosensing for the detection of biological molecules [7, 8]. The incident light could be in resonance with the oscillations of the surface electron at an excitation frequency, resulting in the collective oscillation of the surface plasmons, and it is called an LSPR mode [9]. It is due to the unique optical properties and surface chemistries that Au NPs were used as the promising nanomaterial in numerous different types of sensors such as surface-enhanced Raman scattering (SERS), fluorescence, electrochemical, and fiber optical-based LSPR sensor
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
