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The decellularization protocols applied on the corneal stromal constructs in the literature usually fail to provide a corneal matrix with sufficient mechanical and optical properties since they alter the extracellular matrix (ECM) microstructure. In this study, to overcome these limitations, a hybrid cornea stromal construct was engineered by combining gelatin methacrylate (GelMA) and decellularized ECM. Photo-cross-linking of impregnated cell laden GelMA in situ using different UV cross-linking energies (3200, 6210, and 6900 μJ/cm2) and impregnation times (up to 24 h) within a decellularized bovine cornea enhanced light transmission and restored lost mechanical features following the harsh decellularization protocol. The light transmittance value for optimized hybrid constructs (53.6%) was increased nearly 10 fold compared to that of decellularized cornea (5.84%). The compressive modulus was also restored up to 6 fold with calculated values of 5040 and 870 kPa for the hybrid and decellularized samples, respectively. These values were found to be quite close to that of native cornea (48.5%, 9790 kPa). ATR-FTIR analyses were carried out to confirm the final chemical structure. The degradation profiles showed similar decomposition behaviors to that of native cornea. In vitro culture studies showed a high level of cell viability and cell proliferation rate was found remarkable up to the 14th day of the culture period regardless of selected UV energy level. The methodology used in the preparation of the hybrid cornea stromal constructs in this study is a promising approach toward the development of successful corneal transplants.

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Millions of people require bone injury treatment and there have been many methods suggested for the stabilization of bone fractures. The need for the development of new methods is obvious since current stabilization methods are inadequate. Here, we described the development of polyurethane-based bone adhesives composites containing β-tricalcium phosphate ceramics in different sizes and ratios. To characterize the proposed materials, Fourier transform infrared spectroscopy, hydrogen-nuclear magnetic resonance, differential scanning calorimetry analyses together with scanning electron microscopy observations, and micro-computerized tomography imaging were examined. Furthermore, in vitro performance of the produced materials was tested by using MG63 human osteosarcoma cell line, and an ex vivo modeling study was conducted to test the mechanical performance of resulting materials using bovine rib bone. All materials were exhibited high porosity (above 90%) and homogeneous distribution of ceramic particles. Polyurethane scaffolds containing 40% (w/w) 1–2 mm β-tricalcium phosphate were shown the highest compressive strength as 1.34 ± 0.10 MPa. In addition, 85.75% cell viability was recorded according to the cytotoxicity analysis and also the cell proliferation was found highest in the same group. Taken into account the obtained results, the prepared polyurethane-based bone adhesive materials containing ceramics has a great potential to transform into a final product and meet a clinically significant medical need.

Decellularization of tissues and organs has high potential to obtain unique conformation and composition as native tissue structure but may result in weakened tissue mechanical strength. In this study, poly(glycerol-sebacate) (PGS) elastomers were combined with decellularized aorta fragments to investigate the changes in mechanical properties. PGS prepolymer was synthesized via microwave irradiation and then in situ crosslinked within the decellularized aorta extracellular matrix (ECM). Tensile strength (σ) values were found comparable as 0.44 ± 0.10 MPa and 0.57 ± 0.18 MPa for native and hybrid aorta samples, respectively, while elongation at break (ɛ) values were 261% ± 17%, 7.5% ± 0.57%, and 22.18% ± 2.48% for wet control (native), decellularized dried aortae, and hybrid matrices, showing elastic contribution. Young's modulus data indicate that there was a threefold decrease in stiffness compared to decellularized samples once PGS is introduced into the ECM structure. Scanning electron microscopy (SEM) analysis of hybrid grafts revealed that the construct preserves porosity in medial layer of the vessel. Biocompatibility analyses showed no cytotoxic effects on human abdominal aorta smooth muscle cells. Cell studies showed 98% activity in hybrid graft extracts. As a control, collagen coating of the hybrid grafts was performed in the recellularization stage. SEM analysis of recellularized hybrid grafts revealed that cells were attached to the surface of the hybrid graft and proliferated during the 14 days of culture in both groups. This study shows that introducing an elastomer into the native ECM structure following decellularization process can be a useful approach for the preparation of mechanically enhanced composites for soft tissues.