Plasma surface engineering of biomaterials

The chemical and biological interactions between biomaterials and the outside environment such as tissues and body fluids depend on the surface properties. Low-pressure plasma-based and related technology offers the unique capabilities of modifying selected surface properties and enabling surface functionalization and fabrication of special surface structures to cater to clinical requirements such as mechanical strength, cyto-compatibility, nontoxicity, bacteria resistance, and so on. By using plasma-based techniques, the inherent favorable bulk properties of the materials and biomedical devices can be preserved while selective surface properties such as mechanical strength, hydrophilicity / hydrophobitcity, and chemical reactivity can be enhanced. In particular, plasma immersion ion implantation and deposition (PIII&D) is very useful to biomedical devices such as surgical implants because it is a non-line-of-technique and suitable for biomedical components with a complex shape such as bone fixators, scoliosis correction devices, cardiovascular stents, and artificial heart valves. In this plenary talk, recent research work performed in the Plasma Laboratory of City University of Hong Kong on plasma treatment of biomaterials is described. Examples will include bio-conductive coatings, biodegradable metals and polymers, antibacterial surfaces, and nanostructured biomaterials with favorable delivery and imaging properties.