MoS2 quantum dots featured fluorescent biosensor for multiple detection of cancer

Abstract

Transition metal ions, such as those generated through MoS2 material, possess an intrinsic fluorescence quenching property towards organic dye molecules; thus, they can be used to construct biosensors as quenchers. However, we found that the conventional bulk MoS2 blocks the view of fluorescence imaging, and is incapable of tracing and visualizing mucin 1-overexpression cancer cells. Herein, a FAM fluorophore-labeled ssDNA fluorescent probe (P0-FAM) stacked on the surface of MoS2 quantum dots (QDs) was used to construct a MoS2 QDs-P0-FAM biosensor. MoS2 QDs exhibit a high fluorescence quenching ability towards fluorescent dyes, possess large specific surface area and a large number of active sites to adsorb and quench more fluorescent probes, promoting sensitivity between quenching and the recovery signal. In addition, the lighter color of unstack-MoS2 QDs is beneficial to define the location of cancer cells compared to MoS2 nanosheets. The novel MoS2 QDs-based biosensor demonstrates high sensitivity to MUC1 with a detection limit of 0.5 nM, and may become an important tool toward the detection of cancer cells.