Au-Modified Monolayer MoS₂ Sensor for DNA Detection

Recently, molybdenum disulfide (MoS 2 ) 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 MoS 2 sensor that allows rapid, sensitive, and selective detection of DNA molecules. The Au-thiol bond can effectively enhance the DNA adsorption on MoS 2 . With the increasing concentration of DNA solution, the photoluminescence peak shows a prominent blueshift induced by the decrease of dielectric constant around MoS 2 . The monolayer MoS 2 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 MoS 2 . The density functional theory calculation of MoS 2 /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.