Identification of Different Protein Molecules Using MoS2-Graphene Heterostructure Nanopores

Abstract

MoS2-graphene heterostructure nanopores have shown the potential of detecting single protein molecules with high spatial resolution and slow translocation speed. In this work, we use this new type of nanopore to identify different protein molecules including bovine serum albumin (BSA) and Immunoglobulin G (IgG). The heterostructure nanopores are drilled by FIB and TEM with diameter of ~12 nm. The statistical and single-signal analyses of the single protein molecules translocation are conducted. The results demonstrate that due to stronger interaction with the heterostructure, IgG molecules have much longer dwell time than BSA, while the complete translocation of IgG becomes harder, leading to obvious lower current blockage. Our analysis indicates that heterostructure nanopores are capable of identifying and distinguishing different types of proteins.