Frozen organic particles mapped in stunning new imaging method

Researchers at Tohoku University have developed an advanced cryo-electron microscopy technique that overcomes longstanding challenges in mapping the elemental composition of frozen organic and biological nanoparticles. Traditional cryo-transmission electron microscopy (cryo-TEM) excels at revealing the size and structure of delicate samples preserved in a near-natural frozen state but struggles to accurately identify elemental makeup due to background noise from ice and image drift during scanning. Existing methods like energy-filtered TEM (EF-TEM) and electron energy loss spectroscopy (EELS) often damage samples or produce blurred images, limiting their use primarily to metals or bulk materials. The new approach refines the “3-window method” for background correction to effectively remove interference from ice in frozen samples and incorporates a drift compensation system to stabilize images during long elemental scans. Additionally, a software extension automates energy shift adjustments, enhancing the precision and efficiency of elemental mapping. This breakthrough enabled researchers to clearly visualize silicon distribution in silica nanoparticles as small as 10 nanometers and to map