An Acetylcholine Electrochemical Biosensor Based on Bi-Enzyme Functionalized Nanofiber Composites

This work offered an electrochemical biosensor for acetylcholine (ACh) detection using the bi-enzyme functionalized nanofibers composites-modified glassy carbon electrode (GE). The nanofibers composites (AuNPs@GCS) prepared by electrospinning and electrodeposition techniques, were systematically characterized from micromorphology, active groups, actual areas and impedance, and were used to simultaneously decorate the acetylcholinesterase (AChE) and choline oxidase (ChOx). Bi-enzyme functionalized AuNPs@GCS (AChE-ChOx/AuNPs@GCS) electrode demonstrated the superior loading capacity and stability, was firstly used for the ACh analysis, the detection limit was 0.067 nM, it outperformed or compared to the relevant literatures in terms of linear range and LOD. After systematic methodological evaluation and feasibility verification, this biosensor had good stability, specificity and reproducibility. In human serum samples, the results detected by the biosensor were compared with results tested by Enzyme-linked immunosorbent assay (ELISA). T test was performed for statistical comparisons and p value more than 0.05 was considered no statistical significance. It indicated that this biosensor had a good application prospect in the ACh actual sample detection. This work also provided an efficient and accurate method for quantitative detection of neurotransmitters in complex biological samples.