Here we present an injectable PEG/collagen hydrogel system with robust networks for use as elastomeric tissue scaffolds. Covalently crosslinked PEG and physically crosslinked collagen form semi‐interpenetrating networks. The mechanical strength of the hydrogels depends predominantely on the PEG concentration but the incorporation of collagen into the PEG network enhances hydrogel viscoelasticity, elongation, and also cell adhesion properties. Experimental data show that this hydrogel system exhibits tunable mechanical properties that can be further developed. The hydrogels allow cell adhesion and proliferation in vitro. The results support the prospect of a robust and semi‐interpenetrating biomaterial for elastomeric tissue scaffolds applications.
We fabricated composite fibrous scaffolds from blends of poly(lactide‐co‐glycolide) (PLGA) and nano‐sized hydroxyapatite (HA) via electrospinning. SEM‐EDX and AFM analysis demonstrated that HA was homogeneously dispersed in the nanofibers, and the roughness increased along with the amount of incorporated HA. When hMSCs were cultured on these PLGA/HA composite nanofibers, we found that incorporation of HA on the nanofibers did not affect cell viability whereas increased ALP activity and expression of osteogenic genes as well as the calcium mineralization of hMSCs. Our results indicate that the composite nanofibers can be offered as a potential bone regenerative biomaterial for stem cell based therapies.
Astrocyte‐nanofiber interactions are studied by culturing primary rat cortical astrocytes on poly[caprolactone‐co‐(ethyl ethylene phosphate)] electrospun nanofibers and solvent‐cast films (two‐dimensional control). The results indicate that nanofiber topography significantly suppresses astrocyte proliferation and enhances apoptosis, without altering cellular activation as compared to films. Moreover, nanofiber topography enhances gene‐silencing efficiency in astrocytes. The results suggest that nanofibers may serve as potential substrates for nerve regeneration by suppressing astrocyte growth and may further facilitate the use of gene‐silencing to enhance CNS regeneration.
