In this paper, the gel permeation chromatography of chitosan with different
degrees of acetylation (0 < DA < 60 mol%) was analyzed using cationic poro
us supports in acidic conditions. A light scattering detector allowed the d
etermination of the molecular weight distribution and the variation of the
radius of gyration as a function of the molecular weight. From these data,
the persistence length (L-p) of chitosan as a function of DA is discussed;
the role of the method of preparation of the samples is also pointed out. F
or heterogeneously acetylated chitosan, L-p = 110 Angstrom is found to be i
ndependent on DA in the range 0 < DA < 25 mol%. For homogeneously reacetyla
ted samples, L-p increases slightly from 110 to 150 Angstrom when DA increa
ses up to 60%. These conclusions may be related with the acetyl group distr
ibution along the chains as examined by NMR. (C) 2001 Elsevier Science Ltd.
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