Femtosecond pulsed laser ablation for in-tissue electron cryo-tomography

Cryogenic femtosecond pulsed laser ablation (cryo-fs-PLA) accelerates preparation of vitreous mammalian brain tissue specimens for cryo-ET from thick (>100 m) biopsies.

• Why it matters: Routine cryo-ET in tissue is limited by efficiently producing high-quality, electron-transparent specimens from thick samples.
• What they did: The study uses cryogenic fluorescence microscopy to target regions of interest in high-pressure frozen tissue, defines cryo-fs-PLA parameters, measures ablation rates for two laser wavelengths, and applies cryo-fs-PLA for serial cryogenic lift-out.
• The result: Tilt series from lamellae fabricated from cryo-fs-PLA–exposed sites largely maintain their vitrification state, enabling higher-throughput in situ cell biology in multicellular tissues.