RESUMO
The formation of intramolecular triplex DNA can be regulated by Ag(+) and Cys (cysteine), which switch off/on the fluorescence of the oligonucleotides, 5'-TAMRA-TTC TCT TCC TCT TCC TTC TGA CGA CAG TTG ACT CTT CCT TCT CCT TCT CTT-BHQ-2-3' (Oligo 1) and 3'-GAA GGA AGA GGA AGA GAA-5' (Oligo 2). Based on this principle, sensors for Ag(+) and Cys are developed. The sensor for Ag(+) has a linear range of 2.5 nM-40 nM and a detection limit of 1.8 nM, whereas the sensor for Cys has a linear range of 10.0 nM-120.0 nM and a detection limit of 8.2 nM. Furthermore, the fluorescence is reversible with the alternate addition of Ag(+) and Cys. We constructed a DNA logic gate using Ag(+) and Cys as the input, and the fluorescence intensity as the output. The DNA logic gate is simple; moreover, it has a fast response and good reversibility.
Assuntos
Cisteína/química , DNA/química , Ouro/química , Dicroísmo Circular/métodos , Corantes Fluorescentes/química , Limite de Detecção , Biologia Molecular/métodos , Oligonucleotídeos/química , Reprodutibilidade dos Testes , Prata/química , Espectrometria de Fluorescência/métodosRESUMO
A colorimetric approach to recognize the binding mode between DNA and molecules was developed, which was based upon the electrostatic interaction between DNA and gold colloids.
