"Surface Science at the Biological Interface"

Brian J. Meenan

Northern Ireland Bioengineering Centre (NIBEC), Nanotechnology and Advanced Materials Research Institute, University of Ulster, Newtownabbey, Northern Ireland BT37 0QB

bj.meenan@ulster.ac.uk

The response of biological cells to biomaterial surfaces in the context of how these can influence the function of implantable medical devices is critically dependent upon the nature and scale of the molecular and macromolecular interactions that take place at the interface. The development of surface features that can direct such processes has the potential to improve tissue regenerative in vivo and thereby forms the basis of key areas of regenerative medicine.

The provision of biologically inspired surfaces for the purposes of inducing and controlling specific cellular guidance in vivo has stimulated much research interest. An increasingly important aspect of such studies is the determination of those surface properties that will promote and support early stage bioprocesses that can lead to the formation of viable tissue. The appropriate use of surface analysis techniques provides a means by which the properties of the biomaterial surfaces of interest can be accurately determined and their characteristics correlated directly with the attendant bio-response with the aim of delivering reproducible functionality to the latest generation of implant devices.

In this presentation, the central role of surface analysis in ascertaining the key chemical and topography data from several biomaterial systems will be considered. A number of exemplar studies from recently published and on-going work carried out at the University of Ulster will be used to illustrate how knowledge of surface properties, gained via the appropriate application of relevant analytical methods, can greatly assist in discrimination of the actual interfacial conditions that prevail. Specifically, XPS, ToF-SIMS, XRD, FTIR, SEM and AFM data from studies of osteoblast response to sputter deposited bioactive calcium phosphate (CaP) thin films and the behaviour of lens epithelia cells on plasma modified “inert” PMMA surfaces will be discussed. In each case, results from the corresponding biological (cell culture) studies will be used to indicate how surface analysis data can inform the choice of biomaterial processing needed to achieve a given targeted bio-response.