Solubility and structure of N-carboxymethylchitosan

doi:10.1016/0141-8130(94)90048-5

International Journal of Biological Macromolecules

Volume 16, Issue 4, 1994, Pages 177-180

https://doi.org/10.1016/0141-8130(94)90048-5 Get rights and content

Abstract

$N- Carboxymethylchitosan$ from crab and shrimp chitosans was obtained in water-soluble form by proper selection of the reactant ratio, i.e. using equimolar quantities of glyoxylic acid and amino groups. HPLC determinations of glyoxylic and glycolic acids, in conjunction with NMR analysis, permitted identification of the structure of the product, which is partly $N- mono-carboxymethylated$ (0.3), $N,N- dicarboxymethylated$ (0.3) and $N- acetylated$ depending on the level of deacetylation of the starting chitosan (0.08–0.15). The preparation can be made successfully even in the presence of large concentrations of glycolic acid. The use of enzymes exerting hydrolysing activity on the high-molecular-weight fractions helps to avoid gel formation during storage and precipitate formation on addition of anti-microbial agents.

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Citation Excerpt :
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Solubility and structure of N-carboxymethylchitosan

Abstract

Carbohydr. Res.

Carbohydr. Polym.

J. Chromatogr.

Clin. Chim. Acta

Int. J. Biol. Macromol.

Enzyme Microb. Technol.

Solubility and structure of $N- carboxymethylchitosan$