Tissue Engineering Scaffold Material with Enhanced Cell Adhesion and Angiogenesis from Soy Protein Isolate Loaded with Bio Modulated Micro-TiO₂ Prepared via Prolonged Sonication for Wound Healing Applications

Tissue engineering is a technique that promotes healing by creating an ideal environment for endogenous cells to migrate and grow into the site of injury via a scaffold, improving regeneration and reducing the time required for in vitro cell culture. In this work, the effect of the addition of sonicated TiO₂ in the soy protein isolate (SPI) matrix for tissue engineering applications was studied. In comparison to adding expensive nano TiO₂, this method of incorporating sonicated TiO₂ into the SPI matrix will aid in achieving improved properties at a lower cost. The effect of the addition of sonicated TiO₂ on the morphological, UV transmittance, mechanical, thermal, surface energy, and hydrophilicity of SPI films was investigated. The result shows that the uniformly distributed TiO₂ particles successfully blocked 95% of UV light. Scanning electron microscopy revealed a significant reduction in the TiO₂ agglomerate size and homogeneous distribution of the same when sonication was applied instead of mechanical dispersion. A simultaneous increase of tensile strength (from 3.16 to 4.58 MPa) and elongation at break values (from 24.25% to 95.31%) with 0.5% TiO₂ was observed. The addition of 0.25% TiO₂ was found to significantly enhance the elongation at break value to 120.83%. Incorporation of micro-TiO₂ particles could improve the surface roughness, surface energy, and wettability of SPI films. In vitro cell adhesion studies and in vivo subcutaneous implantation studies were performed to assess the cell growth and angiogenesis of the developed film membranes. An MTT assay showed that SPI-1%TiO₂ film favored cell viability up to 118%, and in vivo subcutaneous implantation studies showed enhanced cell growth and angiogenesis for SPI-1% TiO₂ films. This SPI-TiO₂ film with enhanced surface properties can be used as an ideal candidate for tissue engineering applications.