I would suggest to  use a crio-SEM equipment, which allow work at very low temperature  (– 190 ºC )

"The stabilizationof the chitosan droplets in the emulsion was achieved byionic crosslinking of chitosan with sodium sulphate." Leonor, I. B., Baran, E. T., Kawashita, M., Reis, R. L., Kokubo, T., & Nakamura, T. (2008). Growth of a bonelike apatite on chitosan microparticles after a calcium silicate treatment. Acta biomaterialia, 4(5), 1349-1359.

Distinct shift in the surface plasma absorption maxima was observed after the stabilization of chitosan with the respective drug nano conjugate (Figure3,4)." Biocompatible polymer chitosan stabilized silver nanoparticles-Azithromycin (CS-AgNp-AZ) and levofloxacin (CS-AgNp-LF) drug nano conjugate fabricated wound dressing for the improved anti bacterial activity against human pyogenic bacteria  http://scholarsresearchlibrary.com/dpl-vol7-iss2/DPL-2015-7-2-100-111.pdf

regards

The cryo-TEM  is the best way for the detail characterization with high resolution. But this method is not simple in use.

Sometimes we examine the artificial molecular constructions (virus-like particles, etc.) by TEM and AFM. When the high resolution is not important, it is possible to use very fast and simple technique for TEM sample preparation - negative staining.

https://www.researchgate.net/publication/258169574_Studies_on_the_physicochemical_properties_of_the_new_preparation_deltaferon_as_a_component_of_a_molecular_construct     

Good luck!

Article Studies on the physicochemical properties of the new prepara...

Dear Colleagues

Thanks a lot but unfortunely we have not in Bordeaux University a cryo-TEM or cryo SEM thus we are looking for a another way. Then you answers show us that we have to face cryo-microscope annd sample preparation adapted as mentionned in your articles