Preparation and characterization of polymeric host molecules, β-cyclodextrin linked chitosan derivatives having different linkers.
Reductive alkylation of the amino group of chitosan with β-cyclodextrin (CD) aldehyde derivatives, i.e., 6-deoxy-6-(4-oxobutyramido)-β-CD and 6-oxo-β-CD, gave two β-CD-linked chitosan derivatives with C4 (4-butylamido) and C0 linking arms, respectively. Degree of substitution (D.S.) of both C4-β-CD and C0-β-CD linked chitosan was controlled by the ratio of starting materials. The structures of the products were confirmed by (1)H and (13)C NMR and FT-IR spectra. Their inclusion properties of C4-β-CD (D.S. 18%) and C0-β-CD linked chitosan (D.S. 17%) with a fluorescent probe, 6-(p-toluidino)-2-napthalene-6-sulfonate (TNS) were investigated in acetate buffer (pH 4.3) at 25°C. Continuous variation of Job's method revealed that the stoichiometry of inclusion complex of C4-β-CD linked chitosan-TNS was 1:1, whereas that of C0-β-CD linked chitosan was not 1:1. The stability constant of C4-β-CD linked chitosan determined by Benesi-Hildebrand plot was 2.3×10(3)M(-1). These results suggested that length of the linking arms between CD and chitosan is influenced on their inclusion property.
Division of Environmental Materials Science, Graduate School of Environmental Science, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan.
Wanvisa
W
Buranaboripan
Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Kita, Sapporo 060-8589, Japan.
Weeranuch
W
Lang
Division of Environmental Materials Science, Graduate School of Environmental Science, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan.
Erika
E
Motomura
Division of Environmental Materials Science, Graduate School of Environmental Science, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan. Electronic address: nsaka@ees.hokudai.ac.jp.
Nobuo
N
Sakairi
D048271:Chitosan / Q000737:chemistry*; D004355:Drug Stability; D009282:Naphthalenesulfonates / Q000737:chemistry; D047392:beta-Cyclodextrins / Q000737:chemistry*
D009282:Naphthalenesulfonates; D047392:beta-Cyclodextrins; C571277:chitosan-beta-cyclodextrin; C009497:2-(4-toluidino)-6-naphthalenesulfonic acid; D048271:Chitosan
Chitosan; Fluorescence enhancement; Inclusion complex; Polymeric host; β-Cyclodextrin