Investigation of the effects of alkane phosphonic acid/RGD coatings on cell spreading and the interfacial strength between human osteosarcoma cells and Ti–6Al–4V

This paper presents the results of an experimental study of the effects of alkyl phosphonic acid/RGD complexes on cell spreading and the interfacial strength between human osteosarcoma (HOS) cells and Ti–6Al–4V surfaces. The initial stage of cell spreading is shown to be accelerated by the coatings in 9-day cell culture experiments. The adhesion between human osteosarcoma (HOS) cells and alkyl phosphonic acid/RGD-coated surfaces is also quantified by performing shear assay experiments on coated and uncoated Ti–6Al–4V specimens. These show that the interfacial shear strengths required to detach the HOS cells from the coated/uncoated specimens, increase from approx. 407 Pa (in the case of the uncoated samples) to 80 Pa in the case of the of alkyl phosphonic acid/RGD coated samples. The increase is attributed to the tethering effect of the of alkyl phosphonic acid/RGD complexes on the HOS cells. The implications of the results are then discussed for improving the wound healing and the osseointegration of biomedical implants fabricated from Ti–6Al–4V.