Influence of carbon nanodots on DNA-Thionine interaction. Application to breast cancer diagnosis

In this work we present for the first time the effect of carbon nanodots on the interaction of DNA layers deposited on gold electrodes and Thionine. Spectroscopic, electrochemical and operando spectroelectrochemistry data demonstrate that Thionine interacts with ssDNA or dsDNA to a different extent, depending on the presence or not of carbon nanodots on the electrode surface. Carbon nanodots serve as nanosubstrate for direct immobilization of non-functionalized oligonucleotide, due to the strong interaction of DNA bases with the nanomaterial. The acquired knowledge is applied to develop a new carbon nanodots based disposable DNA biosensor for the selective mutation detection in BRCA1 gene directly in clinical samples, using Thionine as redox indicator. [Display omitted]