Coatings

A modified surface wherein the adhesion or attachment of cells, proteins and/or prions to the modified surface has been minimised or prevented by adjusting the Lifshitz-van der Waals (LW) surface free energy of an unmodified surface to be equal to or approximately equal to the Lifshitz-van der Waals (LW) surface free energy of the cells, proteins and/or prions in a solution and/or whole blood surrounding the surface,

• wherein the surface is modified with a coating of modified diamond-like carbon (DLC),
• wherein the coated surface inhibits bacterial adhesion and colonisation, thrombus adhesion to the surface and foulant formation,
• wherein the surface is one which comes into contact with cells, proteins and/or prions within a living human or animal body,
• wherein the LW surface free energy of the modified surface is in a range of about 25 mN/m to about 45 mN/m, and
• wherein the adhesion or attachment of said cells, proteins and/or prions is minimised or prevented by modifying the surface free energy γLWsurface of the surface in accordance with the Lifshitz-van der Waals (LW) surface free energy of the cells, proteins and/or prions so that:
• γLWsurface≈γLWS,Min
• wherein γLWS,Min is the minimum level of attachment to a surface S and is defined as follows:
• √{square root over (γLWS,Min)}=(½)(√{square root over (γLWcells and/or proteins and/or prions)}+√{square root over (γLWsolution and/or whole blood)})
• where γLWcells, proteins and/or prions is the LW surface free energy of the cells, proteins and/or prions, and γLWsolution and/or whole blood is the LW surface free energy of the solution and/or of whole blood.