基于氧化石墨烯识别特定双螺旋DNA

Sequence specific recognition of double-stranded DNA with graphene oxide

依据三螺旋DNA的形成,以氧化石墨烯为基础建立了一种识别特定序列双螺旋DNA的方法。单链探针DNA能够通过静电引力作用吸附在氧化石墨烯表面,标记在单链DNA末端的荧光探针分子TAMRA由于荧光能量共振转移作用使得其荧光发生淬灭。加入目标双螺旋DNA后,单链探针DNA与目标DNA分子形成三螺旋DNA,探针DNA从氧化石墨烯表面脱附,标记在探针DNA上的荧光分子的荧光恢复。在最佳实验条件下,荧光恢复的强度与探针DNA的浓度在20.0～300.0 nmol/L具有良好的线性关系,检出限为16.9 nmol/L。该方法在DNA药物筛选及基因疾病的诊断方面具有一定的应用前景。

A fluorescent method for sequence specific： recognition of double-stranded DNA（dsDNA） was develop based upon the hybridization of triplex DNA and graphene oxide. Single-stranded DNA （ssDNA） can adsorbed on the surface of graphene oxide （GO） and the fluorescence of TAMRA labeled on ssDNA was quenched because of fluorescence resonance energy transfer. With the addition of target dsDNA, hybridization occurred between the dye labeled ssDNA and the target dsDNA, which induced desorption of ssDNA from the surface of GO, and turned on the fluorescence of the dye. Under the optimum conditions, the enhanced fluorescence intensity was proportional to the concentration of target dsDNA in 20. 0 -300. 0 nmol/L, and the detection limit was found to be 16. 9 nmol/L. This assay provided a rapid method for diagnosing genetic and pathogenic diseases in the future.