Organophosphorus pesticides (OPs) pose a serious threat to the environment and human health. Their widespread use in agriculture leads to contamination of soil, water and food products, which requires the development of effective detection and monitoring methods. In this regard, the creation of highly sensitive biosensors for the determination of OPs is an urgent task.
Acetylcholinesterase (AChE), an enzyme that plays a key role in the nervous system, is a well-established biomarker for detecting OPCs. Inhibition of AChE activity by OPCs results in accumulation of acetylcholine, which can be recorded using various methods.
In this paper, we present a new biosensor based on Al42Cu40Fe16 quasicrystal modified with multi-walled carbon nanotubes with carboxyl groups (MWCNT-COOH) for OCP detection. Quasicrystals have unique physical and chemical properties, such as high hardness, low friction coefficient and excellent corrosion resistance, which makes them promising materials for biosensor applications. Modification of the MWCNT-COOH quasicrystal allows increasing the surface area and improving the adsorption of AChE, which leads to an increase in the sensitivity of the biosensor.
An icosahedral Al-Cu-Fe quasicrystal (QC), which has excellent electrochemical properties, is used for the first time to develop a highly efficient electrochemical acetylcholinesterase (AChE) biosensor for detecting organophosphorus pesticides (OPPs). The said Al42Cu40Fe16 QC is treated by leaching in an alkaline NaOH solution, and then coated with MWCNTs-COOH, which is characterized by high catalytic activity, electrical conductivity and biocompatibility.
The developed innovative electrochemical analysis platform based on leached Al42Cu40Fe16 QC@MWCNTs-COOH (LQC@CNT) enables the determination of acephate in the concentration range from 10-12 M to 10-6 M with a detection threshold of 1.054 × 10-13 M (S/N = 3). In addition, the modified material improves the interaction between AChE and ATCl, as evidenced by the low Michaelis-Menten constant (Km) value of 80 μM.
This study demonstrates the innovative application of Al42Cu40Fe16 QC nanomaterials for efficient detection of OPs in the field of biosensor technology.
The developed biosensor demonstrates high sensitivity and selectivity for OOP determination. The results of the studies show that the use of the Al42Cu40Fe16 quasicrystal modified with MWCNT-COOH allows creating an effective and reliable biosensor for monitoring environmental pollution with OOP. This biosensor can be used for rapid and accurate determination of OOP in various samples, including water, soil and food products.
Author: Xiaolu Li, Yisong Zhao, Jianmin Chen, Yuping Mi, Zhanbing He, Faming Gao
Institute:
Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, P.R. China
State Key Laboratory of Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, P.R. China