Signal Amplification and Near-Infrared Translation of Enzymatic Reactions by Nanosensors.
Angew Chem Int Ed Engl
; 63(9): e202316965, 2024 02 26.
Article
en En
| MEDLINE
| ID: mdl-38100133
ABSTRACT
Enzymatic reactions are used to detect analytes in a range of biochemical methods. To measure the presence of an analyte, the enzyme is conjugated to a recognition unit and converts a substrate into a (colored) product that is detectable by visible (VIS) light. Thus, the lowest enzymatic turnover that can be detected sets a limit on sensitivity. Here, we report that substrates and products of horseradish peroxidase (HRP) and ß-galactosidase change the near-infrared (NIR) fluorescence of (bio)polymer modified single-walled carbon nanotubes (SWCNTs). They translate a VIS signal into a beneficial NIR signal. Moreover, the affinity of the nanosensors leads to a higher effective local concentration of the reactants. This causes a non-linear sensor-based signal amplification and translation (SENSAT). We find signal enhancement up to ≈120x for the HRP substrate p-phenylenediamine (PPD), which means that reactions below the limit of detection in the VIS can be followed in the NIR (≈1000â
nm). The approach is also applicable to other substrates such as 3,3'-5,5'-tetramethylbenzidine (TMB). An adsorption-based theoretical model fits the observed signals and corroborates the sensor-based enhancement mechanism. This approach can be used to amplify signals, translate them into the NIR and increase sensitivity of biochemical assays.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Nanotubos de Carbono
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Año:
2024
Tipo del documento:
Article
País de afiliación:
Alemania