Detection of protein aggregate morphology through single antifouling nanopore

Abstract

In this report, we investigate the potential offered by nanopores for the detection of proteins aggregates. We focus our study on model proteins, such as ß-lactoglobulin, lysozyme and bovine serum albumin, for their different morphology (fibril or spherical) at the early stage of aggregation. In order to avoid the nanopore fouling a SiN nanopore was coated with PEG chain. The PEG polymers adopt a mushroom conformation which prevents the nonspecific adsorption of proteins aggregates. They also allow to extend the nanopore lifetime. Using resistive pulse method, we successfully detect all the protein aggregates. Our results reveal that the intensity of relative current blockade allows to discriminate the morphology of proteins aggregates.