The RF plasma surface chemical modification of nanodiamond films grown on glass and silicon at low temperature

Glass slides (standard 1 × 3 in. size) coated with nanocrystalline diamond were successfully tested for DNA immobilization. The nanodiamond films were grown on glass substrates at temperature below 400 °C, while keeping the excellent material properties of diamond, such as low background luminescence and high optical transparency. The nanodiamond surface to which proteins were attached was functionalized by ultra-thin amino-polymer film in the radio-frequency (RF) plasma discharge of vaporized organosilane coupling agent N-(6-aminohexyl) aminopropyl trimethoxysilane (AHAPS). Several different IR spectroscopy methods (transmission and reflection–absorption spectroscopy (IRRAS), attenuated total reflectance (ATR) and grazing angle reflectance (GAR)) are discussed with respect of their ability of detecting the functional groups on bio-functionalized diamond surface. The IR absorbance spectra of just a few nm thick RF plasma polymer films deposited on nanodiamond surface are presented.