Lipase-Catalyzed Poly(glycerol-1,8-octanediol-sebacate): Biomaterial Engineering by Combining Compositional and Crosslinking Variables

Photocurable and 3D Printable Functional Polyesters to Engineer Elastomeric Scaffolds for Biomedical Applications

Photocurable functional block copolyesters are reported to engineer elastomeric scaffolds for biomedical applications. The polymer backbone is organized by soft and stiff blocks. The functional prepolymer is readily crosslinked by thiol-yne click chemistry under ulraviolet light in the presence of a photo-initiator to form a robust elastomer. The elastomers bear both chemical crosslinks and crystal-domain crosslinks to simultaneously tune the materials' properties, such as mechanical properties and degradation rates. The dual crosslinks can more efficiently tune the mechanical properties compared to the chemical crosslink alone. More importantly, the functional prepolymer is photo-printable to construct elastomeric scaffolds with precise control of pore sizes using the state-of-the-art digital light processing technique. With hydroxyls pendant on the backbone, human umbilical vein endothelial cells prefer to grow on the elastomer surface compared to that of a poly(caprolactone) film. It is believed that these functional photo-polyesters will be useful to construct medical devices for bioengineering research.

Pair of Functional Polyesters That Are Photo-Cross-Linkable and Electrospinnable to Engineer Elastomeric Scaffolds with Tunable Structure and Properties

A pair of alkyne- and thiol-functionalized polyesters are designed to engineer elastomeric scaffolds with a wide range of tunable material properties (e.g., thermal, degradation, and mechanical properties) for different tissues, given their different host responses, mechanics, and regenerative capacities. The two prepolymers are quickly photo-cross-linkable through thiol-yne click chemistry to form robust elastomers with small permanent deformations. The elastic moduli can be easily tuned between 0.96 ± 0.18 and 7.5 ± 2.0 MPa, and in vitro degradation is mediated from hours up to days by adjusting the prepolymer weight ratios. These elastomers bear free hydroxyl and thiol groups with a water contact angle of less than 85.6 ± 3.58 degrees, indicating a hydrophilic nature. The elastomer is compatible with NIH/3T3 fibroblast cells with cell viability reaching 88 ± 8.7% relative to the TCPS control at 48 h incubation. Differing from prior soft elastomers, a mixture of the two prepolymers without a carrying polymer is electrospinnable and UV-cross-linkable to fabricate elastic fibrous scaffolds for soft tissues. The designed prepolymer pair can thus ease the fabrication of elastic fibrous conduits, leading to potential use as a resorbable synthetic graft. The elastomers could find use in other tissue engineering applications as well.