Nanocomposites modified with small amounts of C-60 fullerenes were investigated by means of thermogravimetric analysis and H-1 NMR- and IR-spectroscopy. The nanocomposite materials were generated on the basis of highly dispersed silica and DNA. The findings revealed that a small amount of fullerenes, settled down on the surface of the nanocomposite, leads to significant modifications in the structure of adsorbed water clusters. The radius of the strongly associated water clusters increased and the interphase energy of the nanocomposite-water system decreased. These composites can be used to control a ratio between the weakly and strongly bound clusters of water adsorbed by DNA molecules. (C) 2010 Elsevier B.V. All rights reserved.