Synthesis, Characterization, and Lectin Recognition of Hyperbranched Polysaccharide Obtained from 1,6-Anhydro-d-hexofuranose

• Published in: Biomacromolecules Vol. 12; no. 5; pp. 1891 - 1899
• Main Authors: Hoai, Nguyen To, Sasaki, Akiyoshi, Sasaki, Masahide, Kaga, Harumi, Kakuchi, Toyoji, Satoh, Toshifumi
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 09.05.2011
• Subjects: Applied sciences; Carbohydrate Sequence; Chromatography, Gel; Exact sciences and technology; Furans - chemistry; Lectins - chemistry; Magnetic Resonance Spectroscopy; Methylation; Molecular Sequence Data; Physicochemistry of polymers; Polysaccharides; Polysaccharides - chemistry; Synthetic biopolymers; Ring opening polymerization; Molecular rigidity; Lectin; Aldose; Branched polymer; Molecular structure; Molecular weight viscosity relationship; Cationic polymerization; Concanavalin A; Experimental study; Solution polymerization; Shear viscosity; Hyperbranched polymer; Preparation; Bicyclic compound; Molecular recognition; Oside polymer; Aqueous solution
• ISSN: 1525-7797; 1526-4602
• DOI: 10.1021/bm2002413

1,6-Anhydro-d-hexofuranoses, such as 1,6-anhydro-β-d-glucofuranose (1), 1,6-anhydro-β-d-mannofuranose (2), and 1,6-anhydro-α-d-galactofuranose (3), were polymerized using a thermally induced cationic catalyst in dry propylene carbonate to afford hyperbranched polysaccharides (poly1−3) with degrees of branching from 0.40 to 0.46. The weight-average molecular weights of poly1−3 measured by multiangle laser light scattering varied in the range from (1.02 to 5.84) × 104 g·mol−1, which were significantly higher than those measured by size exclusion chromatography. The intrinsic viscosities ([η]) of poly1−3 were very low in the range from 4.9 to 7.4 mL·g−1. The exponent (α) in the Mark−Houkwink−Sakurada equation ([η] = KM α) of the polymers was 0.20 to 0.33, which is <0.5. The steady shear flow of poly1−3 in an aqueous solution exhibited a Newtonian behavior with steady shear viscosities independent of the shear rate. These viscosity characteristics were attributed to the spherical structures of hyperbranched polysaccharides in an aqueous solution. Poly1−3 contained a high portion of terminal units of 31−43 mol % nonreducing d-hexopyranosyl and d-hexofuranosyl units, in which the d-hexofuranosyl units were 20−44 mol %. Moreover, poly1 and poly2 showed a strong interaction to Concanavalin A due to the cluster effect or multivalent effect of numerous nonreducing saccharide units on their surfaces with binding constants in the range from 1.7 × 104 to 2.7 × 105 M−1.