Wang Jiasheng,Zhang Decheng,Xu Keke,Hui Ni,Wang Dongwei
Dual-mode electrochemical aptasensor based on nitrogen-doped graphene (NG) doped with the conducting polymer polypyrrole (PPy) nanocomposite is proposed for the determination of acetamiprid. NG/PPy was electrodeposited onto the glassy carbon electrode (GCE) using cyclic voltammetry technique. NG/PPy/GCE showed outstanding electrocatalytic activity for the oxidation of nitrite due to “active region” induced by the charge redistribution of carbon atoms. The ultrasensitive dual-mode biosensor for acetamiprid could be easily developed by coupling acetamiprid aptamers with the NG/PPy hybrid. The specific binding between acetamiprid and the aptamers resulted in the increase of differential pulse voltammetry (DPV) signal change and the decrease of chronoamperometry (CA) signal, and the concentration of acetamiprid could be measured. The working potentials of DPV and CA were − 0.2 ~ 0.4 V and − 0.4 ~ 0.4 V (vs. SCE), respectively. The dual-mode acetamiprid biosensor showed a wide linear range from 10 −12 to 10 −7 g mL −1 , with low detection limits of 1.15 × 10 −13 g mL −1 and 7.32 × 10 −13 g mL −1 through DPV and CA modes, respectively. Moreover, owing to high active area and superior conductivity, as well as good electrocatalytic ability, the dual-sensing platform based on NG/PPy nanocomposite supported the quantification of acetamiprid in complex samples. Graphical abstract A dual-mode electrochemical aptasensor based on NG/PPy nanocomposite for acetamiprid detection was proposed through both the increase of differential pulse voltammetry (DPV) signal change and the decrease of chronoamperometry (CA) signal of the nitrite oxidation electrocatalyzed by NG/PPyn in sensors and biosensors.
Hong Yu,Chen Wang,Xinhe Xiong,Bitao Dai,Yang Wang,Zhijie Feng,Hao luo,Jiangxiong Zhu,Guoqing Shen,Yun Deng,Xueqing Geng,Danfeng Wang,Lumei Wang
Acetamiprid (Ace), extensively employed in agricultural production as a substitute for organophosphorus pesticides, poses a potential threat to the environment and human health due to excessive residues. Hence, the development of reliable and convenient techniques to determine Ace levels in the environment holds significant importance. Among various assay methods, nanomaterial-based aptamer-based biosensors (aptasensors) have emerged as efficient and promising tools. In this study, we successfully developed a novel aptasensor for monitoring Ace in the environmental water, utilizing advanced nanomaterials known as Fe-N-C single-atom nanozymes (SAzymes). Fe-N-C SAzymes exhibited excellent catalytic activity, high stability, and complete atom utilization. A facile dual-confinement route was employed for the synthesis of Fe-N-C SAzymes, and their performance as oxidase-like nanozymes was investigated. The synthesized Fe-N-C SAzymes presented distinct oxidase-like activity and demonstrated the capability to interact with a chromogenic indicator-TMB, serving as the signal transduction element in our assay. Furthermore, we found that thiol-modified aptamers could effectively dampen the oxidase-like activity of Fe-N-C SAzymes.Therefore, we successfully developed a Fe-N-C SAzymes assisted detection method for Ace, which exhibited high sensitivity (LOD = 16.9 nM) and selectivity. Overall, this work provides new insights into the design of multifunctional Fe-N-C SAzymes for environmental and biological applications.
危险品化学品经营许可证（带存储）