The relative extension of alginates having different chemical composition
1973; Elsevier BV; Volume: 27; Issue: 1 Linguagem: Inglês
10.1016/s0008-6215(00)82430-1
ISSN1873-426X
AutoresOlav Smidsrød, R. M. Glover, S G Whittington,
Tópico(s)Thermodynamic properties of mixtures
ResumoFrom light-scattering and viscosity experiments, it was found that the relative extension of the three types of "blocks" in alginate increased in the order "MG-blocks" <"MM-blocks"<"GG-blocks", both in 0.1M aqueous sodium chloride and in the unperturbed state. From a comparison with calculated free-rotation dimensions, it was concluded that this was due to a difference in the hindrance to rotation around the glycosidic linkage in the different blocks. Calculations by statistical mechanics, using Kitaygorodsky potential functions for the non-bonded interaction between atomic groups in adjacent dimers, yielded unperturbed dimensions which were in agreement with the above order, only when the L-guluronic acid residue was assumed to adopt the 1C (1C4) conformation.
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