Whole-Cell Imaging at Nanometer Resolutions Using Fast and Slow Focused Helium Ions

摘要: Observations of the interior structure cells and subcellular organelles are important steps in unraveling organ- elle functions. Microscopy using helium ions can play a major role both surface imaging because it provide subnanometer resolutions at cell for slow ions, fast penetrate without significant loss resolution. Slow (e.g., 10-50 keV) ion beams now be focused to dimensions (~0.25 nm), keV microscopy used image surfaces high resolutions. Because ease neutralizing sample charge flood electron beam, charging effects minimal therefore imaged need conducting metallic coating. Fast (MeV) maintain straight path as they pass through cell. Along trajectory, undergoes multiple collisions, each collision small amount energy is lost scattered electron. By measuring total MeV passes cell, we construct an energy-loss that representative mass distribution This work paves way use whole-cell investigations nanometer structural, elemental (via nuclear elastic backscat- tering), fluorescence induced fluorescence) imaging.