Non-destructive electron microscopy imaging and analysis of biological samples with graphene coating

TL;DR

This paper demonstrates that graphene coating enables non-destructive, high-resolution electron microscopy imaging and chemical analysis of biological samples, overcoming limitations of traditional metal coatings.

Contribution

It introduces a novel graphene-coating method that allows simultaneous high-resolution imaging and chemical analysis of biological samples without destructive preparation.

Findings

Graphene coating prevents sample charging during SEM imaging.

Graphene allows effective chemical analysis via EDS on biological samples.

The method preserves biological sample integrity for further analysis.

Abstract

In electron microscopy, charging of non-conductive biological samples by focused electron beams hinders their high-resolution imaging. Gold or platinum coatings have been commonly used to prevent such sample charging, but it disables further quantitative and qualitative chemical analyses by energy dispersive spectroscopy (EDS). Here we report that graphene-coating on biological samples enables non-destructive high-resolution imaging by scanning electron microscopy (SEM) as well as chemical analysis by EDS, utilizing graphene's transparency to electron beams, high conductivity, outstanding mechanical strength, and flexibility. We believe that the graphene-coated imaging and analysis would provide us a new opportunity to explore various biological phenomena unseen before due to the limitation in sample preparation and image resolution, which will broaden our understanding on the life mechanism of various living organisms.