Combination of Silk Fibroin with Acid and with Base

Abstract

A study was made of the dependence on pH of the amounts of hydrochloric acid and of potassium hydroxide that are taken up by silk fibroin at 0° C. The effect of added potassium chloride on this dependence was also investigated, and was shown to be the binding of an increased quantity of acid or base at a given pH. The maximum acid-combining capacity of silk fibroin is 0.13 milliequivalent per gram; the maximum base-binding capacity is greater than 0.90 milliequivalent per gram. The presence of 0.13 to 0.17 milliequivalent of free carboxyl groups in silk fibroin is estimated from the titration curve. The great amount of base bound can be accounted for only if the phenolic hydroxyl groups of tyrosine take part in the equilibria with base. Further evidence that these groups bind base is provided by the greatly decreased amount of base bound by methylated fibroin. CONTENTS Page

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Cite this paper

@inproceedings{Gleysteen2011CombinationOS, title={Combination of Silk Fibroin with Acid and with Base}, author={F. Gleysteen and Milton Harris}, year={2011} }