In this work, tapered/etched multicore fiber (MCF) probes are spliced with multimode fiber (MMF) to fabricate the sensor structure. To improve sensitivity, gold nanoparticles (AuNPs) and molybdenum disulfide nanoparticles (MoS2-NPs) are used to immobilize both probes. Synthesized AuNPs and MoS2-nanoparticles (NPs) have peak absorption wavelengths of 519 nm and 330 nm, respectively. High-resolution transmission electron microscopy is used to examine the morphology of the NPs. The scanning electron microscope is used to characterize the NPs-immobilized optical fiber sensor structures, and SEM-EDX is used to verify the NPs-coating over fiber structure. The functionalization of acetylcholinesterase enzyme over the NPs-immobilized probe increases the specificity of the sensor later on. Finally, the developed sensor probes are tested by detecting various acetylcholine concentrations. In addition, performance analysis such as reusability, reproducibility, and selectivity (in the presence of ascorbic acid, glucose, dopamine, and uric acid) are carried out, and proposed biosensors are experimentally evaluated. The developed tapered fiber sensor with a sensitivity of 0.062 nm/uM can detect even very low concentrations like 14.28 uM over a wide detection range of 0 to 1000 uM.
|Number of pages||9|
|Journal||IEEE Transactions on Instrumentation and Measurement|
|Early online date||7 Dec 2021|
|Publication status||Published - 21 Feb 2022|