文摘
Recently, molybdenum disulfide (MoS2) has attracted considerable attention in the field of biomolecular detection owing to its large surface area and remarkable optoelectronic properties. Here, we report on a novel Au-modified monolayer MoS2 sensor that allows rapid, sensitive, and selective detection of DNA molecules. The Au-thiol bond can effectively enhance the DNA adsorption on MoS2. With the increasing concentration of DNA solution, the photoluminescence peak shows a prominent blueshift induced by the decrease of dielectric constant around MoS2. The monolayer MoS2 nanosheet exhibits different photoluminescence properties toward single-strained DNA versus double-strained DNA. Thus, the complementary target DNA could be distinguished from mismatched DNA through the photoluminescence spectra of MoS2. The density functional theory calculation of MoS2/DNA systems was performed to explore the detection mechanism. This work could promote the research of novel sensing platform by coupling nanomaterials with biomolecular recognition events.