Plasmachemical functionalisation offers a versatile route to surface functionalisation, allowing a wide variety of functional groups to be deposited in a substrate independent process. This thesis presents the application of pulsed plasmachemical functionalisation in two areas. Firstly, the construction of covalently tethered DNA or protein arrays is examined, and novel routes are presented based on the introduction of aldehyde and bromine functions onto substrates such as glass, silicon, polystyrene beads and carbon nanotubes. Secondly, the use of plasmachemical layers for the tethering of metal centres is also presented, with aldehyde and vinylpyridine functional surfaces presented, and their use in the metallization of substrates such as carbon nanotubes demonstrated. The functionalisation and reaction of plasmachemical surfaces is monitored by a variety of surface sensitive methods including XPS, FT-IR, contact angles, and reflectometry.