Chitosan gel sheet containing drug carriers with controllable drug-release properties.

We prepared the "sheet-type hydrogel" (gel sheet), a sheet consisting of PEG-grafted chitosan and cross-linkable polymeric micelles, that were expected to be used for wound healing. We optimized the PEG-modification process, evaluated the strain-dependence of the gel's properties to obtain flexible gel sheets, and evaluated the drug-release properties of the gel sheets. Finally, we succeeded in observing that the release of the antibiotic tetracycline (TET) from the gel sheet in which TET existed only in the cross-linkers was lower than the release of TET from the sheet in which TET was dispersed in the polymer networks. Our research demonstrates that the strategy of incorporating drug carriers into gel sheets might benefit the construction of biomaterials with controllable drug-release properties.