Abstract
A selected hide gelatin has been intensively studied to isolate and identify its natural restrainer. Using mild methods, the impurity has been successively concentrated until finally a fraction was obtained virtually free from gelatin. This proved to be a mixture of DNA and RNA, mainly the former. Its composition, u.v. spectrum, molecular weight, electrophoretic behaviour and photographic activity have been studied. A simplified rapid method of isolation has been developed which should facilitate comparison of gelatins.
Notes
Paper presented at the “Congres International de Science Photographique” held in Paris in September 1965.
We exclude from consideration here the deliberate addition to the gelatin of a stabilizer many of which act as restrainers.