Cryofixation of Tissues for Electron Microscopy: A Review of Plunge Cooling Methods

Authors

Keith P. Ryan, Plymouth Marine Laboratory

Abstract

This review of cryofixation by plunge cooling surveys liquid coolants, plunge cooling devices, modeling and applications featuring time resolution. It then focuses on thermocouple experiments and ice crystal analyses. These highlight the effects of the design of specimen holders, the cold gas above the coolant which can freeze the specimen prematurely, specimen size, plunge velocity, coolant depth and ultimate coolant efficiencies. The ice crystal cavity analyses are validated by experiments which monitor the effects of high subzero temperatures on the storage of plunge cooled specimens and an experiment which monitored the rate of cryosubstitution. Ethane was found to be more efficient for plunge cooling metal specimens (bare thermo-couples), exposed hydrated specimens and metal-sandwiched freeze fracture specimens; this suggests that it should be used for plunge freezing, spray freezing and jet freezing.

Recommended Citation

Ryan, Keith P. (1992) "Cryofixation of Tissues for Electron Microscopy: A Review of Plunge Cooling Methods," Scanning Microscopy: Vol. 6: No. 3, Article 8.
Available at: https://digitalcommons.usu.edu/microscopy/vol6/iss3/8