A kind of novel biodegradable hydrogel made from copolymerization of gelatin with polypseudorotaxanes based on alpha-CDs.

A kind of novel biodegradable supramolecular hydrogel was synthesized via copolymerization of gelatin methacrylamide with photocurable and biodegradable polypseudorotaxanes under UV irradiation. These polypseudorotaxanes were prepared by supramolecular self-assemblies of alpha-cyclodextrins threaded onto amphiphilic LA-PEG-LA copolymers end-capped with methacryloyl groups. The hydrogels are injectable, and their structure was characterized in detail with FTIR, (1)H NMR, XRD, TG and DSC techniques. Their swelling behaviour and morphologies were also examined. The analytical results demonstrated that the channel-type crystalline structure of the polypseudorotaxanes remains in the as-obtained hydrogels. Moreover, the SEM pictures showed that the hydrogels having gelatin methacrylamide are more suitable for cell seeding and proliferation than those without gelatin added.

Synthesis and characterization of three-dimensional crosslinked networks based on self-assemly of α-cyclodextrins with thiolated 4-arm PEG using a three-step oxidation.

A kind of novel three-dimensional crosslinked networks based on the self-assemly of α-CDs with thiolated four-arm PEG was prepared by thiol-disulfide interchange reaction using a three-step oxidation. The supramolecular structure of the resulting hydrogels was characterized FTIR, H NMR, XRD, DSC and TGA measurements. The results demonstrated that the channel-type crystalline structure of inclusion complexes is still maintained after the multi-step oxidation. According to the swelling and degradation tests, the swelling behaviors and degradation properties can be readily regulated by tuning the feed compositions of α-CDs and PEG-thiolated prepolymer. Furthermore, the threading α-CDs clearly protects disulfide bonds from an attack of a reduced form of glutathione as a result of prolonging the degradation time of the hydrogels in water.