Nano-TiO₂ enriched polymeric powder coatings support human mesenchymal cell attachment and growth

The objective of this study was to utilize ultrafine powder coating technology to prepare (PPC) that can support human mesenchymal cell attachment and growth. Resins were modified with titanium dioxide and polytetrafluoroethylene (PTFE), and enriched with either SiO₂ or TiO₂ nanoparticles (nSiO₂ or nTiO₂) to create continuous PPC. Scanning electron microscopy (SEM) revealed complex surface topographies with nano features, and energy dispersive X-ray (EDX) analysis with Ti mapping confirmed a homogenous dispersion of the material. SEM and inverted fluorescence microscopy showed that human embryonic palatal mesenchymal (HEPM) cells attached and spread out on the PPC surfaces, particularly those enriched with nTiO₂. Cell counts were higher, and the MTT assay measured more metabolic activity from the nTiO₂ enriched PPCs. Furthermore, these cellular responses were enhanced on PPC surfaces that were enriched with a higher concentration of nTiO₂ (2% vs. 0.5%), and appeared comparable to that seen on commercially pure titanium (cpTi). Therefore the nTiO ₂ enrichment of PPC was shown to favor human mesenchymal cell attachment and growth. Indeed, this modification of the materials created continuous surface coatings that sustained a favorable cellular response.