Label-free detection of DNA hybridization using transistors based on CVD grown graphene

Abstract

The high transconductance and low noise of graphene-based field-effect transistorsbased on large-area monolayer graphene produced by chemical vapor deposition are used for label-free electrical detection of DNA hybridization.The gate materials, buffer concentration and surface condition of graphene have bee noptimized to achieve the DNA detection sensitivityaslowas 1 pM(10⁻¹² M), whichismore sensitive than the existing report based on few-laye rgraphene. The graphene films obtained using conventional PMMA-assisted transfer technique exhibits PMMA residues, which degrade the sensing performance of graphene. We have demonstrated that the sensing performance of the graphene samples prepared by gold-transfer is largely enhanced (by 125%).