Autoradiograph

An autoradiograph is an image on an X-ray film or nuclear emulsion produced by the pattern of decay emissions (e.g., beta particles or gamma rays) from a distribution of a radioactive substance.

Some autoradiographs can be examined microscopically for localization of silver grains (such as on the interiors or exteriors of cells or organelles) in which the process is termed micro-autoradiography.

[3] In biology, this technique may be used to determine the tissue (or cell) localization of a radioactive substance, either introduced into a metabolic pathway, bound to a receptor[4][5] or enzyme, or hybridized to a nucleic acid.

But because target in the cryosections is widely exposed and can direct contact with radioligand, in vitro autoradiography is still a quick and easy method to screen drug candidates, PET and SPECT ligands.

The distribution of RNA transcripts in tissue sections by the use of radiolabeled, complementary oligonucleotides or ribonucleic acids ("riboprobes") is called in situ hybridization histochemistry.

[12] For example, if sugars accumulate in the minor veins of a leaf, it is expected that the leaves have few plasmodesmatal connections which is indicative of apoplastic movement, or an active phloem-loading strategy.

This autoradiographic approach contrasts to techniques such as PET and SPECT where the exact 3-dimensional localization of the radiation source is provided by careful use of coincidence counting, gamma counters and other devices.

[14] The task of radioactive decontamination following the Baker nuclear test at Bikini Atoll during Operation Crossroads in 1946 was far more difficult than the U.S. Navy had prepared for.

On August 10, Warren showed Blandy an autoradiograph made by a surgeonfish from the lagoon that was left on a photographic plate overnight.

Autoradiography of a coronal brain slice, taken from an embryonal rat. GAD67 -binding marker is highly expressed in the subventricular zone .
Radioactive parts of a fish show as white against a black background.
A radioactive surgeonfish makes its own X-ray. The bright area is a meal of fresh algae. The rest of the body has absorbed and distributed enough plutonium to make the scales radioactive. The fish was alive and apparently healthy when captured.