Amphiphilic derivatives of sodium alginate and hyaluronate: synthesis and physico-chemical properties of aqueous dilute solutions

This paper reports on the synthesis and the physico-chemical characterisation of various amphiphilic derivatives of two natural polysaccharides, sodium alginate and sodium hyaluronate, in which a rather small proportion of the carboxylic groups (less than or equal to 10% mel) was esterified by long alkyl chains (C12H25 or C18H37) The derivatives thus prepared were characterised by gas chromatography, H-1 and C-13 n.m.r. spectroscopy and size exclusion chromatography coupled to a multi-angle laser light scattering detection. The tendency of these water-soluble compounds to hydrophobic association in aqueous solutions was evidenced firstly in dilute regime using capillary viscometry as well as fluorescence spectroscopy in the presence of a molecular probe, 1,1-dicyano-(4'-N,N-dimethylaminophenyl)-1,3-butadiene. (C) 2000 Elsevier Science Ltd. All rights reserved.