X-Ray Microscopy in Berkeley

摘要

A new high resolution soft X-ray microscope (XM-1) has been used in a variety of applications. It is a conventional transmission microscope with a zone plate condenser and objective. A mutual indexing system incorporates state-of-the-art visible light microscopy and precise positioning of samples. XM-1 has a spatial resolution of 43 nm, as measured with a knife edge object, using the 10% to 90% intensities. It is used in collaboration with other groups to investigate variety of mostly biological samples. In our most extensive study, the life cycle of malaria parasites (Plasmodium falciparum) in intact human red blood cells was mapped. Abnormalities in the parasites development with protease inhibitor treatments and membrane protein deficiencies have been investigated and were linked to parasite mortality. New structures in green alga (Chlamydomonas), uniquely visible with soft X-rays, have been confirmed and analyzed in unfixed samples. In addition XM-1 is used to map the morphological variation of genetically altered sperm cells. We also give a brief introduction of the history of X-ray microscopy.