Silicon-Enriched Poly(vinyl alcohol)/Gelatin Hydrogels for 3D Printed Inks

Biomaterials have emerged as a promising approach for tissue engineering because they can mimic various physicochemical properties of tissues and support cell growth and proliferation. Recently, research in this field has focused on developing systems that promote tissue regeneration rather than replacing all damaged tissues. This study compares the synthesis and production of silicon bioceramic nanoparticles through chemical methods with naturally occurring silicon-rich particles known as diatoms. These nanoparticles were incorporated into poly(vinyl alcohol)/gelatin (PVA/Gel) hydrogels to enhance their bioactivity and mechanical behavior. The study began with characterizing ceramic particles using X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and energy-dispersive X-ray analyses. Viability assays determined the optimum amount of CaSiO₃ and diatom to promote cell proliferation in fibroblasts (NIH) and osteoblasts (HFOB). Intriguingly, silica-rich particles improved viability by promoting cell proliferation, which was increased by at least 20% in both cell lines. This suggests that silica-rich particles may mitigate the adverse effect of the hydrogel on cell viability. Finally, a new noncommercial printing system for the preparation of freeze–thaw cross-linked hydrogels was developed, and the possibility of 3D printing of the generated PVA/Gel formulation was verified.