Macroporous Biodegradable Cryogels of Synthetic Poly(α-amino acids)

Abstract

We present an investigation of the preparation of highly porous hydrogels based on biodegradable synthetic poly(α-amino acid) as potential tissue engineering scaffolds. Covalently cross-linked gels with permanent pores were formed under cryogenic conditions by free-radical copolymerization of poly[N(5)-(2-hydroxyethyl)-L-glutamine-stat-N(5)-(2-methacryloyl-oxy-ethyl)-L-glutamine] (PHEG-MA) with 2-hydrohyethyl methacrylate (HEMA) and, optionally, N-propargyl acrylamide (PrAAm) as minor comonomers. The morphology of the cryogels showed interconnected polyhedral or laminar pores. The volume content of communicating water-filled pores was >90%. The storage moduli of the swollen cryogels were in the range of 1-6 kPa, even when the water content was >95%. The enzymatic degradation of a cryogel corresponded to the decrease in its storage modulus during incubation with papain, a model enzyme with specificity analogous to wound-healing enzymes. It was shown that cryogels with incorporated alkyne groups can easily be modified with short synthetic peptides using azide-alkyne cycloaddition "click" chemistry, thus providing porous hydrogel scaffolds with biomimetic features.

Superporous Poly(ethylene glycol) Diacrylate Cryogel with a Defined Elastic Modulus for Prostate Cancer Cell Research

“…For the generation of a scaffold with defined stiffness to culture prostate cancer cells, we first used different molecular weights of PEGda, a nontoxic and nonimmunogenic polymer to create cryogels with the required stiffness. The stiffness was determined following the application of 1 N pressure and a constant compression of 1 mm min −1 .…”

Poly(Hydroxyethyl Methacrylate) Immunoaffinity Cryogel Column for the Purification of Human Immunoglobulin M

“…Following removal of water from swollen cryogels by squeezing, the weights of the squeezed cryogels (m squeezed ; g) were also determined. The macroporosity (%) of cryogels representing the volume fraction (in %) was determined by a method based on water vapor adsorption and was calculated according to Equation (2) [47,48].…”

Colloidally stable polypeptide‐based nanogel: Study of enzyme‐mediated nanogelation in inverse miniemulsion

“…These PAAs, due to their polypeptide backbone, exhibit the potential to be degraded by a range of proteases and peptidases, which are secreted by cells during the treatment. In earlier studies, we demonstrated that the rate and enzyme specificity of poly[ N 5 ‐(2‐hydroxyethyl)‐L‐glutamine] degradation could be considerably modified by side‐chain modification or by the addition of minor amino acids into the polymer chain by copolymerization . The use of PAAs provides the unique possibility to combine the merits of traditional synthetic degradable polymers and natural polymers.…”

“…In earlier studies, we demonstrated that the rate and enzyme specificity of poly[N 5 -(2-hydroxyethyl)-L-glutamine] degradation could be considerably modified by side-chain modification or by the addition of minor amino acids into the polymer chain by copolymerization. [25][26][27] The use of PAAs provides the unique possibility to combine the merits of traditional synthetic degradable polymers and natural polymers.…”