A finite element model to determine the bactericidal and cytotoxic properties of nanopatterned surfaces

Abstract

The fundamentals of the nanopatterned surface can be found on the wings of cicada. These bactericidal surfaces are artificially mimicked on the surface of the implant to reduce the infection rate, which is one of the main complication after joint replacement. The bactericidal properties of the nanopatterned surface are a promising feature. However, the non-cytotoxicity of the surface of the implants should not be compromised. So far, no optimal nanopatterned surface regarding the geometrical features has been found yet. This study focusses on the computational modeling of the nanopatterned surface using Finite Element approaches to simulate the interaction between bacterial cells (Staphylococcus aureus) and host cells (osteoblast) with the nanopatterned surface. The final aim of the project is to show how geometrical features of the nanopatterned surfaces can influence the bacteria’s and cell’s fate. The geometrical parameters of the nanopatterned surface are height, width, interspace, radius and the shape and are varied to create different types of nanopatterned surfaces. The simulations have been performed based on the experimental examination of the bactericidal and cytotoxicity properties of nanopatterned surfaces. From the numerical analysis, it is concluded that among different geometrical parameters of the nanopatterned surface, only width and interspace of the nanopillars have a direct bactericidal effect. The nanopatterned surface with a small/intermediate width (50 nm) in combination with a large interspace (300 nm) has been found as the most optimal nanopattern resulting in bactericidal properties and non-cytotoxic properties for host cells. The results of this project can be considered as a guideline for the proper design of geometry of nanopatterned surfaces and can be verified by further experimental investigations.