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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.

Monodisperse silica microspheres with bimodal pore-size distribution were proposed as a high performance sorbent for DNA isolation in batch fashion under equilibrium conditions. The proposed sorbent including both macroporous and mesoporous compartments was synthesized 5.1 μm in-size, by a "staged shape templated hydrolysis and condensation method". Hydrophilic polymer based sorbents were also obtained in the form of monodisperse-macroporous microspheres ca 5.5 μm in size, with different functionalities, by a developed "multi-stage microsuspension copolymerization" technique. The batch DNA isolation performance of proposed material was comparatively investigated using polymer based sorbents with similar morphologies. Among all sorbents tried, the best DNA isolation performance was achieved with the monodisperse silica microspheres with bimodal pore size distribution. The collocation of interconnected mesoporous and macroporous compartments within the monodisperse silica microspheres provided a high surface area and reduced the intraparticular mass transfer resistance and made easier both the adsorption and desorption of DNA. Among the polymer based sorbents, higher DNA isolation yields were achieved with the monodisperse-macroporous polymer microspheres carrying trimethoxysilyl and quaternary ammonium functionalities. However, batch DNA isolation performances of polymer based sorbents were significantly lower with respect to the silica microspheres.

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