Liquid-Cell Electron Microscopy of Adsorbed Polymers.

Citation data:

Advanced materials (Deerfield Beach, Fla.), ISSN: 1521-4095, Vol: 29, Issue: 41

Publication Year:
Mentions 5
News Mentions 4
Blog Mentions 1
Social Media 1
Tweets 1
Repository URL:
Nagamanasa, Kandula Hima, Wang, Huan, Granick, Steve
Wiley-Blackwell, WILEY-V C H VERLAG GMBH
Materials Science, Engineering
Most Recent Tweet View All Tweets
Most Recent Blog Mention
Most Recent News Mention
article description
Individual macromolecules of polystyrene sulfonate and poly(ethylene oxide) are visualized with nanometer resolution using transmission electron microscopy (TEM) imaging of aqueous solutions with and without added salt, trapped in liquid pockets between creased graphene sheets. Successful imaging with 0.3 s per frame is enabled by the sluggish mobility of the adsorbed molecules. This study finds, validating others, that an advantage of this graphene liquid-cell approach is apparently to retard sample degradation from incident electrons, in addition to minimizing background scattering because graphene windows are atomically thin. Its new application here to polymers devoid of metal-ion labeling allows the projected sizes and conformational fluctuations of adsorbed molecules and adsorption-desorption events to be analyzed. Confirming the identification of the observed objects, this study reports statistical analysis of datasets of hundreds of images for times up to 100 s, with variation of the chemical makeup of the polymer, the molecular weight of the polymer, and the salt concentration. This observation of discrete polymer molecules in solution environment may be useful generally, as the findings are obtained using an ordinary TEM microscope, whose kind is available to many researchers routinely.

This article has 0 Wikipedia reference.