Sputter Deposition of Titanium on Poly(Methyl Methacrylate) Enhances Corneal Biocompatibility

et al. 2021

Sci Rep

Self Cite

Gelatin methacryloyl (GelMA) is one of the most widely used photo-crosslinkable biopolymers in tissue engineering. In in presence of an appropriate photoinitiator, the light activation triggers the crosslinking process, which provides shape fidelity and stability at physiological temperature. Although ultraviolet (UV) has been extensively explored for photo-crosslinking, its application has been linked to numerous biosafety concerns, originated from UV phototoxicity. Eosin Y, in combination with TEOA and VC, is a biosafe photoinitiation system that can be activated via visible light instead of UV and bypasses those biosafety concerns; however, the crosslinking system needs fine-tuning and optimization. In order to systematically optimize the crosslinking conditions, we herein independently varied the concentrations of Eosin Y [(EY)], triethanolamine (TEOA), vinyl caprolactam (VC), GelMA precursor, and crosslinking times and assessed the effect of those parameters on the properties the hydrogel. Our data showed that except EY, which exhibited an optimal concentration (~ 0.05 mM), increasing [TEOA], [VA], [GelMA], or crosslinking time improved mechanical (tensile strength/modulus and compressive modulus), adhesion (lap shear strength), swelling, biodegradation properties of the hydrogel. However, increasing the concentrations of crosslinking reagents ([TEOA], [VA], [GelMA]) reduced cell viability in 3-dimensional (3D) cell culture. This study enabled us to optimize the crosslinking conditions to improve the properties of the GelMA hydrogel and to generate a library of hydrogels with defined properties essential for different biomedical applications.

Section: Methodsmentioning

confidence: 99%

Systematic optimization of visible light-induced crosslinking conditions of gelatin methacryloyl (GelMA)

et al. 2021

Sci Rep

Self Cite

“…Nonproliferative surfaces can induce ECM-related stress in cultured cells and lead to myofibroblasts differentiation and α-SMA overexpression, which are involved in pro-inflammatory and fibrotic responses. 51 When cultured on constructs, HCS did not express α-SMA. These data suggest that GM-VP construct is biocompatible and promotes cell adhesion and proliferation, while preserving the phenotypic characteristics of HCS.…”

Section: ■ Results and Discussionmentioning

confidence: 98%

Photo-cross-linked Gelatin Glycidyl Methacrylate/N-Vinylpyrrolidone Copolymeric Hydrogel with Tunable Mechanical Properties for Ocular Tissue Engineering Applications

et al. 2021

ACS Appl. Bio Mater.

Self Cite

Corneal transplantation is currently the primary treatment for corneal blindness. However, severe global scarcity of donor corneas is driving the scientific community to find novel solutions. One potential solution is to replace the damaged tissue with a biocompatible artificial cornea. Here, gelatin glycidyl methacrylate (GM) and N-vinylpyrrolidone (VP) were cocrosslinked to afford a hybrid bicomponent copolymeric hydrogel with excellent mechanical, structural, and biological properties. Our studies showed that the GM/VP ratio can be adjusted to generate a construct with high tensile modulus and strength of 1.6 and 1.0 MPa, respectively, compared to 14 and 7.5 MPa for human cornea. The construct can tolerate up to 22.4 kPa pressure before retention sutures can tear through it. Due to the presence of a synthetic component, it has a significantly higher stability against collagenase induced degradation, yet it is biocompatible and promotes cellular adhesion, proliferation, and migration under in vitro settings.

“…After 1, 4, and 7 days of cell culture, the specimens were stained with standard Live–Dead staining kit (LIVE/DEAD viability/cytotoxicity kit, for mammalian cells, Thermofisher Scientific, Cambridge, MA) and imaged by inverted fluorescent microscopy (Zeiss Axio Observer Z1; Thornwood, NY). Cell viabilities were quantified by using ImageJ software from multiple images acquired from each sample ( n = 4) and compared to those cultured on TCP as a control and as described elsewhere. , …”

Section: Methodsmentioning

confidence: 99%

“…Cell viabilities were quantified by using ImageJ software from multiple images acquired from each sample (n = 4) and compared to those cultured on TCP as a control and as described elsewhere. 39,40 The alamarBlue Assay. To assess the metabolic activity of the cultured cells (HCEp and HCS) when grown on the constructs, we used a standard alamarBlue assay.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

Graphene-Lined Porous Gelatin Glycidyl Methacrylate Hydrogels: Implications for Tissue Engineering

et al. 2021

ACS Appl. Nano Mater.

Self Cite

Despite rigorous research, inferior mechanical properties and structural homogeneity are the main challenges constraining hydrogel's suturability to host tissue and limiting its clinical applications. To tackle those, we developed a reverse solvent interface trapping method, in which organized, graphene-coated microspherical cavities were introduced into a hydrogel to create heterogeneity and make it suturable. To generate those cavities, (i) graphite exfoliates to graphene sheets, which spread at the water/ heptane interfaces of the microemulsion, (ii) heptane fills the microspheres coated by graphene, and (iii) a cross-linkable hydrogel dissolved in water fills the voids. Cross-linking solidifies such microemulsion to a strong, suturable, permanent hybrid architecture, which has better mechanical properties, yet it is biocompatible and supports cell adhesion and proliferation. These properties along with the ease and biosafety of fabrication suggest the potential of this strategy to enhance tissue engineering outcomes by generating various suturable scaffolds for biomedical applications, such as donor cornea carriers for Boston keratoprosthesis (BK).