Intrinsic oxidase-mimicking activity of nitrite upon visible light illumination and its colorimetric detection in saliva.
Talanta
; 279: 126649, 2024 Nov 01.
Article
en En
| MEDLINE
| ID: mdl-39098240
ABSTRACT
Small molecules with enzyme-like properties have recently attracted considerable attention. Herein, we discovered that nitrite possesses intrinsic oxidase-mimicking activity upon visible light, catalyzing the oxidation of the typical chromogenic substrate in the absence of H2O2. Notably, nitrite exhibited a markedly high value of Kcat, approximately 4, 7, and 4000-fold greater than that of Acr+-Mes, Eosin Y, and Diacetyl, respectively. Comprehensive investigation elucidated that O2â¢â» and â¢OH are the primary reactive oxygen species (ROS) responsible for the oxidation of 3,3',5,5'-tetramethylbenzidine dihydrochloride hydrate (TMB). Leveraging the linear correlation between the absorbance of oxidized TMB (oxTMB) at 652 nm and nitrite concentration, a simple colorimetric approach for nitrite detection was successfully established in the range of 1-75 µM with a detection limit of 0.14 µM. Moreover, the proposed strategy could be applied to determine the nitrite concentration in saliva, exhibiting a great prospect for clinical diagnosis. This work contributes novel insights into the exploration of small-molecule enzyme mimics.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Saliva
/
Colorimetría
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Luz
/
Nitritos
Límite:
Humans
Idioma:
En
Año:
2024
Tipo del documento:
Article