A turn-on fluorescence assay of alkaline phosphatase activity based on an enzyme-triggered conformational switch of G-quadruplex.
Talanta
; 208: 120453, 2020 Feb 01.
Article
em En
| MEDLINE
| ID: mdl-31816768
ABSTRACT
Herein, a turn-on fluorescence assay was introduced for alkaline phosphatase (ALP) detection based on ThT/G-quadruplex system. The basis of the method is that chelation of guanine bases at the binding sites by Ag+ blocks G-quadruplex formation and decreases the fluorescence intensity sharply. In the presence of ALP, ascorbic acid 2-phosphate (AAP) is hydrolyzed to form ascorbic acid (AA) which in turn reduces Ag+ to Ag0. As a result, the blockage ability of Ag+ is disrupted which augments the fluorescence intensity and relies on the concentration of ALP. Under the optimized parameters (500â¯nM DNA probe; 6⯵M Ag+; 1â¯mM AAP; 30â¯min for Ag+ and DNA probe reaction time), fluorescence intensity correlates linear range between 1 and 100 U/L of ALP concentration with the detection limit of 0.503 U/L. In the inhibition assay, 50% of ALP inhibition is caused by Na3VO4 with a concentration of 0.254â¯mM. Furthermore, the assay was used to detect ALP activity in human serum samples in which the results were significant. Above all, the proposed strategy is potential, facile, and sensitive for analyzing ALP activity and screening ALP inhibitor.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fosfatase Alcalina
/
Quadruplex G
Limite:
Humans
Idioma:
En
Revista:
Talanta
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
China