Toward Compositional Contrast by Cryo-STEM

This Account describes efforts to introduce scanning transmission electron microscopy (STEM) for cryo-electron microscopy (cryo-EM) and tomography of biological specimens. Cryo-EM excels at preserving native elemental composition, but conventional TEM is limited in quantitatively interpreting pixel intensities for compositional information. STEM, using incoherent elastic scattering, offers compositional contrast via its sensitivity to atomic number (Z). The authors explore STEM's application in life science cryo-EM, detailing various detection modes and their advantages for different applications, including cryo-scanning transmission electron tomography (CSTET). They also discuss the challenges and future developments in cryo-STEM, including high-resolution phase imaging techniques.

Michael Elbaum, Shahar Seifer, Lothar Houben, Sharon G. Wolf, Peter Rez