Photocurable Albumin Methacryloyl Hydrogels as a Versatile Platform for Tissue Engineering

Abstract

Photopolymerization of protein-derived polymers functionalized with methacryloyl groups has been increasingly used to fabricate three-dimensional tissue constructs for biomedical applications because photocurable protein-based polymers (e.g., gelatin and collagen methacryloyl) feature spatial-temporal controllability of engineering complex constructs as well as inherent biological properties. Herein, we report photocurable albuminbased hydrogels. First, photocurable bovine serum albumin methacryloyl (BSA-MA) with different degrees of substitution (DM) was successfully synthesized in a precise manner, without substantially altering BSA native secondary structure. Resultant photocurable BSA-MA hydrogels exhibited tunable physio-biochemical properties over the swelling, degradation, and mechanical properties. Moreover, photo-cross-linked BSA-MA hydrogels provided a permissible environment to support cell viability and functionality both in two-and three-dimensional culture systems. Photocurable BSA-MA hydrogels may be used as a versatile platform for various bioapplications including tissue engineering and 3D bioprinting.

Photocurable antimicrobial silk‐based hydrogels for corneal repair

“…In this study, all groups showed water content values similar to the human cornea (75%–85%) 45,48 . However, as previously reported in the literature, the mass swelling of SilkMA hydrogels decreased with higher polymer concentrations 10,49–51 . An increase in the concentration of photocrosslinkable groups results in a higher crosslinking density, which ultimately creates a tighter hydrogel network and a lower mass swelling ratio.…”

“…Ferraci et al synthesized 10%, 15%, and 20% photocurable bovine serum albumin (BSA‐MA) with different degrees of substitution (DM = 73%–100%) using UV light (150 mW/cm 2 , 6 min). The compressive modulus of 15 and 20% BSA‐MA hydrogels with 92 DM% was ~18 and 30 kPa, respectively 10 . In this work, despite using a considerably lower DM% (40%) and intensity (3 mW/cm 2 ), the compressive modulus of 15% and 20% SilkMA hydrogels was 21 and 79 kPa, respectively.…”

“…A negative correlation between the polymer concentration and the polymer reactivity to enzymatic degradation was observed. At higher cross‐linking densities, the enzyme accessibility to the cleavage sites of SF is restricted, decreasing the reactivity of hydrogels to enzymatic degradation 10 . However, the in vitro degradation rate reported in this study is not representative of the ocular in vivo microenvironment.…”

“…However, SilkMA hydrogels were shown to support adhesion and proliferation of HDFs for the entire duration of the experiment and the differences between the metabolic activity in SilkMA and GelMA cell‐laden hydrogels was only statistically significant at day 1 ( p <.0001). The attachment of HDF cells to the SilkMA hydrogels possibly resulted from the hydrophilic nature of the hydrogels and their ability to immobilize adhesive proteins from the serum (e.g., vitronectin and fibrinogen) 10,65 . In the future, the viability of cells encapsulated within SilkMA gels should be studied to confirm the suitability of SilkMA as biomaterial and study the impact of photocrosslinking.…”

“…9 Due to the limitations of current clinical strategies, there has been extensive research focused on the use of polymeric biomaterials to replace damaged corneal tissue. 2,4 The use of injectable polymeric biomaterials such as hydrogels are favorable as they can either be administered directly to the corneal injury and crosslinked in situ using different methods 2,4,[10][11][12][13] or 3D printed into complex and anatomically relevant geometries. 5,6,14,15 Upon implantation the artificial corneal substitute should act as a functional cornea nurturing tissue ingrowth and regeneration with low inflammatory host response.…”