Tapered Optical Fiber-Based LSPR Biosensor for Ascorbic Acid Detection

Abstract

The ascorbic acid (AA) is a biomarker that can be used to detect the symptoms of severe disorders such as scurvy, Parkinson’s, Alzheimer’s, and cardiovascular diseases. In this work, a simple and effective sensor model is developed to diagnose the presence of AA samples. To develop the sensor, a tapered single-mode optical fiber has been used with the well-known phenomenon of localized surface plasmon resonance (LSPR). For LSPR, the tapered region is immobilized with synthesized gold nanoparticles (AuNPs) and zinc oxide nanoparticles (ZnO-NPs) whose absorbance peak wavelengths appear at 519nm and 370nm, respectively. On the basis of nanoparticles (NPs) configurations, two different biosensor probes are developed. In the first one, the sensing region is immobilized with AuNPs and named Probe I. In the second probe, the immobilized layer of AuNPs is further coated with a layer of ZnO-NPs, and a resultant probe is termed as Probe II. The characterizations of synthesized AuNPs and developed fiber probes are done by the ultraviolet-visible (UV-vis) spectrophotometer, high-resolution transmission electron microscope (HR-TEM), atomic force microscopy (AFM), and scanning electron microscope (SEM). To enhance the selectivity, a sensing region of probes is functionalized with ascorbate oxidase enzyme that oxidizes the AA in the presence of oxygen. The response of developed sensor probes is authenticated by sensing the samples of AA in the range from 500 nM to 1 mM, which covers the range of AA found in human bodies, i.e., 40µM–120µM. The performance analysis of the developed sensor probes has been done in terms of their stability, reproducibility, reusability, and selectivity. To observe the stability of AA, a pH-test has also been done that results in a better solubility of AA molecules in phosphate-buffered saline (PBS) solution.

[Retracted] Solanum tuberosum Leaf Extract Templated Synthesis of Co3O4 Nanoparticles for Electrochemical Sensor and Antibacterial Applications

“…The intake of both AA and CA contents decreases below or above the standard and recommended amount results in severe sickness and general disorderness [ 6 ]. So, now-a-days, numerous electrochemical and analytical determination protocols for the determination of AA and CA have been developed such as titration, chromatography, colorimetry, fluorescence, spectrophotometry, capillary electrophoresis, voltammetry, fluorometry, spectrometry, chemiluminescence, and enzymatic approaches [ 2 , 7 ].…”

Optical Fiber, Nanomaterial, and THz-Metasurface-Mediated Nano-Biosensors: A Review

“…On the other hand, MMF allows multiple modes to propagate along the fiber due to its large core diameter (50–100 µm) [ 7 ]. In general, the fiber-based biosensors comprise a thin metallic film or nanostructure along the length of the sensing area to excite the surface plasmon resonance (SPR) or localized surface plasmon resonance (LSPR), which can be later immobilized with various antibodies or sensing materials for target-specific detection [ 8 , 9 ]. The sensing configuration based on the SPR or LSPR effect can be excited from the evanescent field extended into the cladding region and interacted with deposited metals [ 10 , 11 , 12 ].…”

Biosensing Applications Using Nanostructure-Based Localized Surface Plasmon Resonance Sensors

“…The use of optical fibers as LSPR substrates has several advantages, including resistance to electromagnetic interference, chemical passivity, cost reduction, ease of use, and small footprint [ 76 , 77 ]. Easy reuse of the optical fiber-based LSPR sensor is also one advantage [ 75 , 78 , 79 , 80 , 81 ]. The general approach to reuse is to wash with phosphate buffered saline buffer or sodium dodecyl sulfate solution, and cut and polish the end of the used facet of the optical fiber.…”