title: Glucosamine oligomers: 4. Solid state-crystallization and sustained dissolution.
abstract: When glucosamine oligomers are stored in the solid state they undergo a process of crystallization. The extent to which this occurs depends on whether the samples are isolated in the -NH3+ or -NH2 form, on the storage time, and on the degree of polymerization of the isolated oligomer. The allomorph obtained by this process seems to correspond to the so-called 'tendon-chitosan'. Dissolution of such aged oligomer samples gives rise to a process of dissociation of the associated chains in the crystal, leading to the establishment of a pseudo-equilibrium between single and associated oligomer chains and hence the simultaneous presence of the 'monomeric', 'dimeric', 'trimeric', etc., forms of the oligomer. The phenomenon cannot be attributed to a process of aggregation in solution. The effects of various parameters on this behaviour have been investigated.
authors.affiliation: Laboratoire d'Etudes des Matériaux Plastiques et des Biomatériaux, URA CNRS no. 507, Université Claude Bernard Lyon I, Villeurbanne, France.
authors.forename: A
authors.initials: A
authors.lastname: Domard
authors.forename: N
authors.initials: N
authors.lastname: Cartier
mesh_terms: D002845:Chromatography; D003460:Crystallization; D005944:Glucosamine / Q000737:chemistry*; D007700:Kinetics; D011108:Polymers / Q000737:chemistry*; D012996:Solutions
chemical_list: D011108:Polymers; D012996:Solutions; D005944:Glucosamine