A Highly Sensitive and Selective Label‐free Electrochemical Biosensor with a Wide Range of Applications for Bisphenol A Detection

Background: Bisphenol A (BPA) is considered one of the most common chemicals that could cause environmental endocrine disrupting. Therefore, there is an increasing demand for simple, rapid and sensitive methods for BPA detection that result from BPA leaching into foods and beverages from storage containers. Herein, a simple laccase electrochemical biosensor was developed for the determination of BPA based on Screen-Printed Carbon Electrode (SPCE) modified graphenegold/ chitosan. The synergic effect of graphene-gold/chitosan nanocomposite as electrode modifier greatly facilitates electron-transfer processes between the electrolyte and laccase enzyme, thus leads to a remarkably improved sensitivity for bisphenol A detection. Methods: In this study, laccase enzyme is immobilized onto the Screen-Printed Carbon Electrode (SPCE) modified Graphene-Decorated Gold Nanoparticles (Gr-AuNPs) with Chitosan (Chit). The surface structure of nanocomposite was studied using different techniques including Field Emission Scanning Microscopy (FESEM), TRANSMISSION Electron Microscopy (TEM), Raman spectroscopy and Energy Dispersive X-ray (EDX). Meanwhile, the electrochemical performances of the modified electrodes were studied using Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV). Results: The developed laccase biosensor offered excellent analytical performance for the detection of BPA with a sensitivity of 0.271 μA/μM and Limit of Detection (LOD) of 0.023 μM, respectively. Moreover, the constructed biosensor showed good reproducibility, selectivity and stability towards BPA. The sensor has been used to detect BPA in a different type of commercial plastic products as a real sample and satisfactory result was obtained when compared with the HPLC method. Conclusion: The proposed electrochemical laccase biosensor exhibits good result which is considered as a promising candidate for a simple, rapid and sensitive method especially in the resource- limited condition.

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Optimization of the Electrodeposition of Gold Nanoparticles for the Application of Highly Sensitive, Label-Free Biosensor

Biosensors ◽

10.3390/bios9020050 ◽

2019 ◽

Vol 9 (2) ◽

pp. 50 ◽

Cited By ~ 3

Author(s):

Hao-Chun Chiang ◽

Yanyan Wang ◽

Qi Zhang ◽

Kalle Levon

Keyword(s):

Gold Nanoparticles ◽

Signal Amplification ◽

Electrochemical Biosensor ◽

Aqueous Electrolyte ◽

Label Free ◽

Reduction Step ◽

Glucose Biosensors ◽

Highly Sensitive ◽

Amperometric Glucose Biosensors ◽

Aunp Surface

A highly sensitive electrochemical biosensor with a signal amplification platform of electrodeposited gold nanoparticle (AuNP) has been developed and characterized. The sizes of the synthesized AuNP were found to be critical for the performance of biosensor in which the sizes were dependent on HAuCl4 and acid concentrations; as well as on scan cycles and scan rates in the gold electro-reduction step. Systematic investigations of the adsorption of proteins with different sizes from aqueous electrolyte solution onto the electrodeposited AuNP surface were performed with a potentiometric method and calibrated by design of experiment (DOE). The resulting amperometric glucose biosensors was demonstrated to have a low detection limit (> 50 μM) and a wide linear range after optimization with AuNP electrodeposition.

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