The viability of U-2 OS cells on Zinc Oxide nanowires observed via MTS assay in vitro

U-2 OS, an Osteosarcoma cell line was incubated on Zinc Oxide nanowire (ZnO NW) arrays of differing morphology for 72 hours at different seeding densities. MTS assays were conducted to ascertain the viability of the cells and the biocompatibility of ZnO NWs. It was found that the viability of the U-2 OS cell line when subjected to a high concentration of ~1.22μg/ml NWs lies between ~71-96% and ~68-72% for substrates with a precursor chemical ratio of 2:1 and 1:1, respectively. It was observed that the shape of the NWs determined the viability of cells on the NWs; which was attributed to changes in the surface area available for cell adhesion. It was determined that the increased surface area of the 2:1 NW array provides a higher area for interaction and formation of focal adhesions compared to arrays formed from the smaller, pointier 1:1 NW array that inhibit cell proliferation due to non adhesive gaps.