Modifying biomaterial surfaces with bioactives to control infection

This chapter discusses representative examples of strategies used for reducing infections associated with biomedical implants and devices, which are caused by the attachment of bacteria and their subsequent biofilm formation on device surfaces. A number of approaches have been shown to produce surfaces/coatings that confer resistance to such bacterial colonisation. Particular emphasis is placed on plasma-based technologies, as plasma polymerisation, in particular, is a technology that is transferable between a large range of different materials and hence can be applied to a variety of biomedical devices and implants without having to re-optimise each time, and without the need for specific substrates. A popular strategy continues to be the use of silver ions or silver nanoparticles in polymer matrices. Another popular approach comprises the use of quaternary amine compounds on surfaces. In both cases, antibacterial activity is indeed obtained, but damage to human cells and tissue remains a concern. Alternative approaches utilising the covalent immobilisation of antibiotic molecules are discussed.