LAUSR

Remarkable progress in correlative light and electron cryo-microscopy (cryo-CLEM) has been made in the past decade. A crucial component for cryo-CLEM is a dedicated cryo-fluorescence microscope (cryo-FM). Here, we describe an ultra-stable super-resolution cryo-FM that exhibits excellent thermal and mechanical stability. The temperature fluctuations in 10 h are less than 0.06 K, and the mechanical drift over 5 h is less than 200 nm in three dimensions. We have demonstrated the super-resolution imaging capability of this system (average single molecule localization accuracy of ∼13.0 nm). The results suggest that our system is particularly suitable for long-term observations, such as single molecule localization microscopy (SMLM) and cryogenic super-resolution correlative light and electron microscopy (csCLEM).