A Novel Method for Frictional Testing on Adherent Cells

Understanding the physical interaction between biomaterials and tissues within the body is critical for the development of medical devices. For instance, the coefficient of friction between the two must be low enough to avoid damaging the cells that make up the tissue. Therefore, a method for obtaining friction data on cells is needed. In the present work, human corneal epithelial (HCE-T) cells are cultured within specialized cell holders and friction experiments are performed with a micro-tribometer. Cell damage is assessed via microscopy and a trypan blue viability assay. Preliminary experiments provide data for an intact monolayer of HCE-Ts being abraded by the glass pin of the micro-tribometer. The coefficient of friction for the glass pin rubbing on an intact cell layer is 0.037 ± 0.016. Additionally, these data show a direct correlation between the friction coefficients obtained and the amount of cell damage that occurs. The protocols developed thus far can be used to conduct friction testing on various adherent cell types (e.g.epithelial cells, endothelial cells, etc.). Furthermore, the micro-tribometer set-up can be modified in order to obtain friction coefficient measurements between cells and various biomaterials.