What does autoradiogram mean?
An autoradiogram is a photographic image produced by placing a radioactively labelled specimen — such as a tissue section, electrophoresis gel, or chromatography plate — against X-ray film or a photographic emulsion. Radiation emitted from the labelled molecules within the specimen exposes the film directly, so the resulting pattern of darkened areas reveals exactly where those molecules are located. The technique behind it, autoradiography, has been a cornerstone of biological research for decades, enabling scientists to track DNA fragments, map neurotransmitter receptors, follow metabolic pathways, and measure cell proliferation. The term derives from Greek roots meaning 'self' plus the Latin-derived element for ray, together with 'gram', something written — aptly describing an image the sample writes of itself through its own emissions. Autoradiogram is used almost exclusively in scientific contexts and is interchangeable in most cases with the closely related term autoradiograph.
nounAn autoradiogram is an image produced on X-ray film or photographic emulsion by the radiation emitted from a radioactive substance in a specimen placed in contact with it. The technique, known as autoradiography, is widely used in biology and medicine to visualize where radioactively labelled molecules are located.
- An image formed on photographic film or emulsion by radiation from a radioactively labelled substance placed in contact with it, used to localize the label in a tissue, gel, chromatograph, or other specimen.
"The autoradiogram revealed precisely which brain regions had taken up the labelled glucose."
"After several weeks of exposure, the autoradiogram showed silver grains densely clustered over the cells that had incorporated the tritiated thymidine."
"The researchers scanned each autoradiogram and quantified the band intensities to measure gene expression levels."
Regular English plural; used when referring to multiple films or images produced in an experiment or series of exposures.
"All twelve autoradiograms were digitized for quantitative analysis."
The word literally means 'self-written by radiation' — the image draws itself from the radioactive decay inside the sample, no camera required.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of autoradiogram
Autoradiogram combines three classical elements: Greek 'autos' meaning self, the international scientific combining form 'radio-' from Latin 'radius' meaning ray, and Greek '-gramma' meaning something written or drawn, via French '-gramme'. The term arose in the late nineteenth century alongside early experiments showing that radioactive substances could expose photographic plates without a lens or light source. It shares these roots with words like autograph, diagram, and radiography.
Related word forms
How autoradiogram is actually used
Autoradiogram is a technical term confined largely to laboratory and scientific writing, particularly in molecular biology, histology, and nuclear medicine. It is essentially interchangeable with the slightly more common 'autoradiograph'; both terms appear in the literature, with usage varying between authors and fields. Plural: autoradiograms.
Easily confused with autoradiogram
A radiogram (or radiograph) is an image made using external X-rays passing through a body, whereas an autoradiogram records radiation emitted from within a radioactively labelled specimen itself.