Our work is directed towards preparing supported catalysts from nanoparticles prepared in solution. In this presentation, we discuss the preparation of supported Au and NiAu catalysts using PAMAM dendrimers as nanoparticle templates. The nanoparticles were then extracted from the dendrimer templates with alkyl thiols to form monolayer protected clusters (MPCs). The MPCs were then deposited onto a commercial titania and the thiols were removed. The new catalysts were characterized (TEM, XPS, and infrared spectroscopy of adsorbed CO) and evaluated for low temperature (263-293 K) CO oxidation activity. Kinetic studies showed that the Au catalysts prepared from MPCs were kinetically equivalent to a standard gold test catalyst. Incorporating Ni into Au nanoparticles increased the catalyst's affinity for oxygen and dramatically lowered the apparent activation energy for CO oxidation. Variation of these properties with Ni content of the nanoparticles will be discussed, as will the use of catalytic test reactions as a characterization tool for nanoparticle materials.