CHARACTERIZATION OF POLYSACCHARIDE SOLUTIONS BY MEANS OF CHROMATOGRAPHY-MULTIDETECTION

Size exclusion chromatography (SEC) combined with double detection, utilizing a differential refractive index (DRI) - and a low angle laser light scattering (LALLS) - detector represents a powerful experimental set-up in the field of chromatography-multidetection (C-MD). By means of these techniques high-quality information for profound polymer characterization is provided in a fast and semi-automatical (autosampler/PC-controlled) way. Molecular characteristics such as molecular weight distributions,molecular weight averages, tendencies for intermolecular interactions, can be obtained by these techniques. Successful handling of data from C-MD-techniques within reasonable time ranges requires adequate hardware and software. This is especially true if advanced data processing is applied, e.g. to yield polymer particle size/shape characteristics in terms of Staudinger /Mark/Houwink constants (K,a) , distributions of sphere equivalent particle radii (R(e)D) -, sphere equivalent mass density of solved polymer coils (rho(e)D) - and intrinsic viscosity ([eta]D) . For aqueous solutions of polysaccharide samples (waxy maize starch hydrolyzate, hydroxyethyl-amylopectin from waxy maize hyrdolyzate, dextran) data from SEC-DRI/LALLS and universal calibration experiments are utilized for a comprehensive physico-chemical characterization of these polymers.