Eric Solon Publishes on Autoradiography Techniques and Quantification of Drug Distribution in Cell and Tissue Research

Using radiolabeled drug compounds is the most efficient way to quantify the amount of drug in a biological specimen. This article is an overview of autoradiographic techniques for measuring drug and drug metabolite levels in biological samples, with examples of how these methods have been applied in recent drug research. Methods discussed include: autoradiography, quantitative whole-body autoradiography, and microautoradiography (MARG).

In autoradiography, radioactively labeled molecules or fragments are visualized using X- ray film, phosphor imaging plates, beta imaging systems, or photo-nuclear emulsions. This technique has been used to quantify and localize drugs in tissues and cells for decades.

Quantitative whole-body autoradiography or autoradioluminography (QWBA) is a phosphor imaging technology that has revolutionized the conduct of drug distribution studies. It delivers high resolution images of the spatial distribution and tissue concentrations of drug-related radioactivity throughout the bodies of laboratory animals. This tissue-specific pharmacokinetic (PK) compartmental analysis helps delineate toxicology, pharmacology, and drug disposition/patterns, and aids in predicting human exposure to drugs and metabolites or radioactivity from radiolabeled drug studies.

Microautoradiography (MARG) is another autoradiographic technique that qualitatively localizes radiolabeled compounds at the cellular level in histological preparations. This article includes a discussion of the technical complexity of obtaining drug concentration data from MARG samples.

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