The non-organically supported silver nanoparticles produced via the reduction of silver oxide by hydrogen and acetvlacetone (acac) have unusual stability in aqueous solution. We have previously reported that the negative potential, the hydrophilic surface that is created by the adsorbed hydroxide ions, which resembles an oxide interface, and the low ionic strength of the solution due to the small salt concentrations in this synthetic approach all contribute to the unusual stability of the colloidal suspension. However, their stability with pH variation has not been well documented. In order to use these silver nanoparticles for biological relevance understanding of their suspension stability characteristics at different pH values is crucial. This work is investigating more methods of synthesizing similar naked nanoparticles and their stability as a function of different pH levels.
 Redox Catalysis on “Naked” Silver Nanoparticles. Getahun Merga, Robert Wilson, Geoffrey Lynn, Bratoljub H. Milosavljevic, and Dan Meisel; J. Phys. Chem. C, 2007, 111 (33), pp 12220–12226
Available at: http://works.bepress.com/getahun_merga/2/