Development of a fluorescent DNA sensor for dual detection of heavy metal ions utilising DAPI in distinct buffers.
Food Chem
; 451: 139390, 2024 Sep 01.
Article
en En
| MEDLINE
| ID: mdl-38653103
ABSTRACT
The DNA-based biosensor utilises a thymine/guanine(T/G)-rich ODN-4 scaffold with 4',6-diamidino-2-phenylindole(DAPI) as a fluorescent emissary to monitor mercury/lead(Hg(II)/Pb(II)) ions simultaneously. Key to its bifocal detection capability is the twin unbound cytosine(C) bases strategically bridging the G-quadruplex and T-rich sequences, enabling their synergistic interplay. It facilitates the recognition of Hg(II)/Pb(II) ions, characterised by high specificity, and effectively mitigates interference from silver(Ag(I)). The G-quadruplex, guided by the C bases, induces a conformational transition in T-Hg(II)-T complexes, resulting in intense fluorescence. Pb(II) causes a spatial shift in the G-quadruplex, relaxing the T-Hg(II)-T base pairs and attenuating the fluorescence signal. The ODN-4 exhibits a robust, linear correlation with Hg(II) concentration (4.09 nmol/L to 1000 nmol/L) and Pb(II) concentration (3.22 nmol/L to 5 µmol/L). Recovery rates in milk, tap water, and rice water specimens with both ions validate method accuracy (Hg(II) 95.19% to 104.68%, Pb(II) 98.20% to 103.46%). It holds promising prospects for practical food analysis.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
ADN
/
Técnicas Biosensibles
/
Colorantes Fluorescentes
/
Indoles
/
Mercurio
Límite:
Animals
Idioma:
En
Revista:
Food Chem
Año:
2024
Tipo del documento:
Article
País de afiliación:
China
Pais de publicación:
Reino Unido