Interpenetrating network gelatin methacryloyl (GelMA) and pectin-g-PCL hydrogels with tunable properties for tissue engineering

Abstract

The design of new hydrogel-based biomaterials with tunable physical and biological properties is essential for the advancement of applications related to tissue engineering and regenerative medicine. For instance, interpenetrating polymer network (IPN) and semi-IPN hydrogels have been widely explored to engineer functional tissues due to their characteristic microstructural and mechanical properties. Here, we engineered IPN and semi-IPN hydrogels comprised of a tough pectin grafted polycaprolactone (pectin-g-PCL) component to provide mechanical stability, and a highly cytocompatible gelatin methacryloyl (GelMA) component to support cellular growth and proliferation. IPN hydrogels were formed by calcium ion (Ca2+)-crosslinking of pectin-g-PCL chains, followed by photocrosslinking of the GelMA precursor. Conversely, semi-IPN networks were formed by photocrosslinking of the pectin-g-PCL and GelMA mixture, in the absence of Ca2+ crosslinking. IPN and semi-IPN hydrogels synthesized with varying ratios of pectin-g-PCL to GelMA, with and without Ca2+-crosslinking, exhibited a broad range of mechanical properties. For semi-IPN hydrogels, the aggregation of microcrystalline cores led to formation of hydrogels with compressive moduli ranging from 3.1 to 10.4 kPa. For IPN hydrogels, the mechanistic optimization of pectin-g-PCL, GelMA, and Ca2+ concentrations resulted in hydrogels with comparatively higher compressive modulus, in the range of 39 kPa-5029 kPa. Our results also showed that IPN hydrogels were cytocompatible in vitro and could support the growth of three-dimensionally (3D) encapsulated MC3T3-E1 preosteoblasts in vitro. The simplicity, technical feasibility, low cost, tunable mechanical properties, and cytocompatibility of the engineered semi-IPN and IPN hydrogels highlight their potential for different tissue engineering and biomedical applications.

Development of Multi-Dimensional Cell Co-Culture via a Novel Microfluidic Chip Fabricated by DMD-Based Optical Projection Lithography

“…Three-dimensional culture for tissue engineering usually requires cells to be maintained with high activity over a long period; thus, the survival period for three-dimensional cultured cells can be extended to 5 days or even several weeks. For instance, Fares et al analyzed the survival rates of MC3T3-E1 cells encapsulated in GelMA and GelMA/pectin-g-PCL hydrogels over 5 days [33], and Pi et al recorded the viability of vascular cells printed using a multichannel coaxial extrusion system over 14 days [34]. The cells cultured in our microfluidic chips here had similar activity to those in the above two studies.…”

Synthesis and characterization of osteoinductive visible light‐activated adhesive composites with antimicrobial properties

“…Cell viability, spreading, and metabolic activity were determined using a commercial LIVE/DEAD assay (Invitrogen), fluorescent F‐actin/DAPI staining, and a commercial PrestoBlue kit (Fisher), respectively, at days 1, 3, and 5 (Fares et al, ; Soucy et al, ). Fluorescent images were acquired using a Zeiss Axio Observer Z1 inverted microscope and analyzed with the ImageJ software (NIH).…”

Polycaprolactone as biomaterial for bone scaffolds: Review of literature

“…Further, these hydrogels showed increased growth of pre-osteoblasts cells in vitro, therefore, have great potential for bone regeneration. 62 When Young's moduli of electrospun PCL fiber and PCL fiber scaffolds was measured using macro-tensile testing instrument, and atomic force microscopy, Young's modulus for fiber scaffold was 3.8 ± 0.8 MPa while for single fiber was 3.7 ± 0.7 GPa. The difference was due to the random structure of fiber scaffold.…”