H. J. Griffiths, C. Collier, A. Markaki, J. Curran, T. Clyne, Univeristy of Cambridge, Cambridge, United Kingdom
The strength of adhesion at the cell-substrate interface is an important parameter in the design of many prosthetic implant material surfaces, due to the desire to create and maintain a strong implant-tissue bond. A systematic study has been carried out on a series of oxide coated Ti6Al4V-based substrates with a range of surface morphologies and chemistries. Oxide coatings were formed using Plasma Electrolytic Oxidation. Cells were seeded at a low concentration onto substrates and cultured for a few days to ensure adhesion of viable cells. The normal and shear strength of osteoblasts (bone cells) and chondrocytes (cartilage cells) adhered to these substrates was measured using accelerated negative buoyancy within an ultracentrifuge. The variation in adhesive strengths, to the range of coatings, is discussed and a comparison is also made between the normal and shear strengths of the bonds and between the two cell types.
Summary: Potential biomedical coatings for Ti-based alloys have been produced using Plasma Electrolytic Oxidation (PEO). The adhesive strengths (normal and shear) of cells bonded to these surfaces are measured in this in vitro study. Measurements are made using accelerated negative buoyancy to attempt to remove adherent cells from the coatings. The study aims to identify the prefered characteristics of the coatings present in terms of morphology and chemistry.