ISTerre, Université Grenoble Alpes, CS, Grenoble Cedex 9

Presented here is a protocol for cell culture on silicon nitride membranes and plunge-freezing prior to X-ray fluorescence imaging with a synchrotron cryogenic X-ray nanoprobe. When only room temperature nano-analysis is provided, the frozen samples can be further freeze-dried. These are critical steps to obtain information on the intracellular elemental composition.

This protocol presents a detailed procedure to prepare biological cryosamples for synchrotron-based X-ray absorption spectroscopy experiments. We describe all the steps required to optimize sample preparation and cryopreservation with examples of the protocol with cancer and phytoplankton cells. This method provides a universal standard of sample cryo-preparation.

This protocol describes the preparation of in vitro bovine articular cartilage for imaging in high resolution with X-rays. These explants actively undergo postnatal maturation. We describe here the necessary steps from the biopsy to data analysis of 3D X-ray phase contrast imaging, passing through explant culture, tissue fixation and synchrotron preparation.