Nano-Jewels in Biology. Gold and Platinum on Diamond Nanoparticles as Antioxidant Systems Against Cellular Oxidative Stress

Diamond nanoparticles (DNPs) obtained by explosive detonation have become commercially available These commercial DNPs cna be treated under fenton conditions (FeSO4 and H2O2 at acidic pH) to obtain purer DNP smaple with a small avarage particle size (4 nm) and a large population of surface OH groups (HO-DNPs) These Fenton treated HO-DNPs have been used as a support of gold and platinum nanoparticles (<= 2 nm average size) Thes resulting meterials (Au/HO-DNP and Pt/HO-DNP) exhibit a high antioxidant activity against reactive oxygen species induced in a hepatoma cell line In addition to presenting good biocompatibility, Au/HO- and Pt/HO-DNP exhibit about a tow fold higher antioxidant activity than glutathione, one of the reference antioxidant systems The most active material against cellular oxidative stress was Au/HO-DNP