Molecular mass distribution analysis of ethyl(hydroxyethyl)cellulose by size-exclusion chromatography with dual light-scattering and refractometric detection

Summary, in English

Dual low-angle light scattering and refractometric detection coupled to size-exclusion chromatography provided proof for the presence of a low amount of stable aggregates/particles in ethyl(hydroxyethyl)cellulose. Unlike the correct size-exclusion chromatographic behavior of the parent polysaccharide itself, the aggregates exhibit variable size-dependent weak retention as a function of flow-rate and of ionic strength of the aqueous mobile phase. Therefore, determination of the molecular mass of non-aggregated polymer is possible in aqueous mobile phase containing 0.1 M NaCl under conditions at which aggregates are completely adsorbed on the column packing irrespective of the flow-rate used. Flow-rate and ionic strength-dependent variations of aggregate behavior as well as model size-exclusion experiments with latex particles indicate that they partly carry a minute charge and have a compact structure. Their weak retention under the separation conditions used suggests a difference in their surface chemistry when compared with the dissolved polymer coils which exhibit a correct size-exclusion behavior. (C) 2002 Elsevier Science B.V. All rights reserved.

• Author: B Porsch; Mats Andersson; B Wittgren; Karl-Gustav Wahlund
• Department/s: Centre for Analysis and Synthesis
• Publishing year: 2002
• Language: English
• Pages: 69-81
• Publication/Series: Journal of Chromatography A
• Volume: 946
• Issue: 1-2
• Links: http://dx.doi.org/10.1016/S0021-9673(01)01572-2
• Document type: Journal article
• Publisher: Elsevier
• Topic: Analytical Chemistry
• Keywords: detection; ethyl(hydroxyethyl)cellulose; LC
• Status: Published
• ISBN/ISSN/Other: ISSN: 0021-9673