Preparation and characterization of a novel Si-containing crosslinkable<Emphasis Type="Italic"> O</Emphasis>-butyrylchitosan

O-Butyrylchitosan is a water-soluble chitosan derivative which is not sufficiently durable for use as an antithrombogenic coating. A crosslinkable O-butyrylchitosan was studied to improve its stability and durability. The process included preparation of methoxysilyl-terminated butyrylchitosan (MOS-OCS) by Michael addition of (3-acryloxypropyl)trimethoxymethylsilane to the amino groups of O-butyrylchitosan and Si-containing crosslinkable butyrylchitosan was obtained by hydrolysis and condensation of methoxysilyl groups in the MOS-OCS. The mechanical properties of crosslinkable butyrylchitosan films were investigated by mechanical testing. The film with 20 mol% (3-acryloxypropyl)trimethoxymethylsilane as crosslinking agent had good mechanical characteristics. All the samples made were colorless, flexible films, with hydrogel structure. Blood-clotting and platelet adhesion assay confirmed that Si-containing crosslinkable butyrylchitosan had good antithrombogenic properties.