1. A technique for covalently attaching a label or marker molecule onto another molecule such as a protein.
The label, which is often fluorescent or radioactive, contains a group that becomes chemically reactive when illuminated usually with ultraviolet light) and will form a covalent linkage with an appropriate group on the molecule to be labelled: proximity is essential. The most important class of photoreactive groups used are the aryl azides, which form short lived but highly reactive nitrenes when illuminated.
(31 Dec 1997)
Lexicographical Neighbors of Photoaffinity Labelling
