New methods to determine the extent of reaction of epichlorohydrin with maltodextrins

The reaction of epichlorohydrin with maltodextrins has been studied using n ovel methods for determining free glycerol and glycerol monoethers. Glycero l is determined by enzymatic analysis and glycerol monoethers by a modified oxidative method involving the HPLC separation and the determination of fo rmaldehyde as the 2,4 dinitrophenylhydrazone derivative. Chloride is determ ined by a standard gravimetric; assay involving silver precipitation. These methods permit the deduction of the overall yield of grafting and the degr ee of cross-linking in the crude reaction medium with no need for further p urification thus allowing the study of the reaction of epichlorohydrin with polysaccharides other than high molecular weight starch or dextrans. Other reaction intermediates such as chloropropanediol and glycidol can also be concluded to be produced, based on the kinetics of the hydrolysis reaction. (C) 1999 Elsevier Science Ltd. All rights reserved.