Macroporous Hydrogels Composed Entirely of Synthetic Polypeptides: Biocompatible and Enzyme Biodegradable 3D Cellular Scaffolds

Abstract

Synthetic polypeptides are a class of bioinspired polymers with well demonstrated biocompatibility, enzyme biodegradability, and cell adhesive properties, making them promising materials for the preparation of macroporous hydrogels as 3D cellular scaffolds. Three-dimensional macroporous hydrogels composed entirely of biocompatible and enzyme biodegradable synthetic polypeptides have thus been prepared. Under cryoconditions, macroporous hydrogels in the form of macroporous cryogels were prepared using a single copolymer component through direct EDC/sulfo-NHS zero-length cross-linking between poly(l-glutamic acid) (PLG) and poly(l-lysine) (PLL) residues on a PLG-r-PLL random copolypeptide chain. The resulting macroporous cryogels were found to contain large interconnected pores (≥100 μm) highly suitable for tissue engineering applications. Tuning the relative ratios of the amino acid components could result in cryogels with very different pore structures, swelling, and mechanical properties, suitable for developing gels for a range of possible soft tissue engineering applications. These cryogels were shown to be enzymatically biodegradable and demonstrated excellent biocompatibility, cell attachment and cell proliferation profiles with mammalian fibroblast (NIH-3T3) cells, demonstrating the appeal of these novel cryogels as highly suitable cellular scaffolds.

Spider-silk inspired polymeric networks by harnessing the mechanical potential of β-sheets through network guided assembly

“…Synthesis of L -valine NCA (Val NCA). L -valine NCA was synthesised using a modified procedure from previously reported literature 44 . Briefly, L -valine (43 mmol, 5 g) was suspended within 80 mL of anhydrous THF in a two-necked round bottom flask under argon.…”

“…However, it should be noted that although it is well known that alanine forms β-sheets at low molecular weight (small blocks), high molecular weight (larger blocks) alanine has been shown to form α-helices [41][42][43] . Our group has had previous success using valine NCA ROP to form β-sheets, making valine a viable option for constructing spider-silk inspired materials 44 .…”

Preparation of chitosan and carboxymethylcellulose‐based polyelectrolyte complex hydrogel via SD‐A‐SGT method and its adsorption of anionic and cationic dye

“…The porosity of PECH was measured by the cyclohexane method . The freeze‐dried PECH was weighted and then immersed in cyclohexane for 1 hr.…”

Promoting Endothelialization of Polymeric Cardiovascular Biomaterials

“…The fibers that comprise the ECM are smaller in diameter than the diameter of the cells, and the ECM provides many important functions such as mechanical support for the adherent cells, promoting cellular orientation, and maintenance of cellular phenotype . Generating polymeric scaffolds that replicate the nanometer‐to‐micron‐scale of the ECM is a proven method for modulating the behaviour of adherent cells, and a wide variety of scaffold fabrication techniques have been developed including particle leaching, phase inversion, micromolding, etching, cryogelation, electrospinning and others . Substrate topography has been shown to be a key regulator of many critical endothelial cell behaviours including adhesion, morphology, migration, proliferation, and gene expression during in vitro culture .…”