Iodination of Keratin


FOR the purposes of another investigation, it has been found necessary to devise a method of iodinating the tyrosine side-chains of keratin exclusively and completely. With aqueous solutions of iodine (0.1 N), no more than 75 per cent of the tyrosine of wool was iodinated under the best conditions used (64 hr. at 22.2° C. and pH 9). It has, however, been found that almost complete conversion into 3 : 5-di-iodotyrosine is obtained by treating wool (0.421 gm.) with a 0.78 N solution of iodine in absolute alcohol (50 c.c.) for 72 hr. at 25° C.


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RICHARDS, H., SPEAKMAN, J. Iodination of Keratin. Nature 171, 751 (1953).

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