Single nanozyme-based colorimetric biosensor for dopamine with enhanced selectivity via reactivity of oxidation intermediates  

作　　者：Caixia Zhu Qing Hong Kaiyuan Wang Yanfei Shen Songqin Liu Yuanjian Zhang 

机构地区：[1]Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Devices,Jiangsu Province Hi-Tech Key Laboratory for Bio-Medical Research,School of Chemistry and Chemical Engineering,Medical School,Southeast University,Nanjing 211189,China

出　　处：《Chinese Chemical Letters》2024年第10期399-403,共5页中国化学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.22174014 and 22074015)。

摘　　要：Reliable and selective sensing of dopamine(DA)is essential for early diagnosis of mental diseases.Among the various potential methods,nanozyme-based sensing systems have demonstrated promising sensitivity and reliability.However,owing to the lack of substrate specificity,it is challenging to selectively detect DA using nanozymes.Herein,based on the reactivity of the DA oxidation intermediates,we report a cascade colorimetric sensing system for the selective detection of DA using only a single nanozyme.It was disclosed that the oxidation product of DA catalyzed by Co-N-doped carbon sheets(Co-N-C,a common oxidase-like nanozyme),dopamine quinone(DAQ),showed significant biocatalytic electron-donating activity in the reduction of O_(2)to generate O_(2)·-.Further using O_(2)·-to oxidize3,3,5,5-tetramethylbenzidine(TMB),a colorimetric sensing platform for DA was constructed with a linear detection range of 50 nmol/L to 50μmol/L and a low limit of detection of 4 nmol/L.Thanks to the reactivity of the oxidation product,without any biometric units(such as nucleic acids,enzymes,and antibodies/antigens),the reaction selectivity of DA against other interferences(e.g.,ascorbic acid,adrenaline,5-hydroxytryptamine,and glutathione)was enhanced up to 71-fold.Beyond complicated cascade systems requiring at least two nanozymes,sophisticated artificial recognition via multiple interactions was simplified by exploiting the oxidative properties of product intermediates;thus,only a single common oxidase-like nanozyme was needed.This work offers a new strategy to enhance the selectivity of nanozymes for bioanalytical applications.

关 键 词：Nanozyme COLORIMETRY SELECTIVITY DOPAMINE Artificial recognition 

分 类 号：O657.3[理学—分析化学] TP212.3[理学—化学]