Contact microscopy with synchrotron radiation.

Soft X-ray contact microscopy with synchrotron radiation offers the biologist, and especially the microscopist, a way to morphologically study specimens that could not be imaged by conventional TEM, STEM, or SEM methods (i.e., hydrated samples, samples easily damaged by an electron beam, electron-dense samples, thick specimens, unstained, low-contrast specimens) at spatial resolutions approaching those of the TEM, with the additional possibility to obtain compositional (elemental) information about the sample as well. Although flash X-ray sources offer faster exposure times, synchrotron radiation provides a highly collimated, intense radiation that can be tuned to select specific discrete ranges of X-ray wavelengths or specific individual wavelengths that optimize imaging or microanalysis of a specific sample. This paper presents an overview of the applications of X-ray contact microscopy to biological research and some current research results using monochromatic synchrotron radiation to image biological samples.