Development of an effective electrochemical platform for highly sensitive DNA detection using MoS2 - polyaniline nanocomposites

Abstract Molybdenum disulfide (MoS 2 ) and its associated nanocomposites are widely explored in different applications like capacitance, batteries, sensing etc. However, the nanosheet formation of MoS 2 exhibits excellent properties for DNA adsorption without any further surface or probe DNA modification which makes it a suitable matrix for the less explored DNA sensing application. In this present work, an ultrasensitive electrochemical DNA biosensor, based on few layered MoS 2 nanosheets blended with conducting polymer, polyaniline is constructed as a sensing platform and used as a DNA sensing probe via differential pulse voltammetric technique. The sensor works well even at concentrations as low as 10 −15 M of target DNA without labeling or any use of amplifiers. The sensing performances show highly satisfactory results in case of serum samples and in presence of other interferrants. In addition, the sensor can successfully recognize any positional mismatch in a known concentration of targeted DNA which can lead to a DNA mismatch senor in near future. The detection method described here expands the application of MoS 2 in the biosensor field with a viable alternative for easy, cost effective electrochemical DNA detection technique with mismatch identification capability.