High Resolution X-ray Microscopy of Frozen Hydrated Samples

Extract

X-ray microscopy is a rapidly developing field stimulated by the development of brilliant X-ray sources and high resolution X-ray lenses. It provides higher resolution than optical microscopy and higher penetration power than electron microscopy. Therefore, X-ray microscopy allows high resolution imaging of thick hydrated samples. The two dominating processes determining the contrast in X-ray microscopy are photoelectric absorption and phase shift. For this reason X-ray microscopy can be performed in amplitude and phase contrast. The Göttingen X-ray microscope at the BESSY electron storage ring in Berlin is operating in both contrast modes and is used for different application fields, for example in biology, biophysics, medicine, colloid chemistry, and soil sciences.

Especially biological objects are sensitive to ionizing radiation. Theoretical investigations show that X-ray images of frozen-hydrated specimen can be obtained without radiation induced artifacts. Therefore, an object stage for cryogenic specimen was developed and implemented on the Gottingen transmission X-ray microscope (TXM) at the electron storage ring BESSY.