Enzyme-aided characterization of carboxymethylcellulose with conventional and novel distribution of functional groups

A method has been developed for the characterization of carboxymethylcellul ose (CMC), which gives a certain insight into the distribution of substitue nts along the cellulose chain. The method is based on the endoglucanase-cat alysed fragmentation of the polysaccharide, followed by preparative size-ex clusion chromatography (SEC). The material of each SEC fraction is subseque ntly converted into monosaccharides by acid hydrolysis, followed by quantit ative HPLC determination of the individual building units of CMC. Basic differences were found for CMC samples, prepared according to differe nt synthesis concepts. CMC-material prepared according to the traditional s lurry method excelled by a relatively homogeneous distribution of substitue nts. However CMC specimen from a newly developed synthesis concept behaved completely different. Endoglucanase-cleaved fragments could be isolated, wh ich were either rather high or rather low in their degree of substitution. This finding proves the existence of a novel blockwise substitution pattern .