Physical properties of ultrafine particles: (A) EPR spectra of CuO/Silica and CuO/Silica exposed to 2-monochlorophenol at 230°C (MCP230). (B) Data showing the calculated size of MCP230 by flow cytometry. (C) Transmission electron micrograph of 100–200 nm Cab-o-sil Silica particles, containing CuO nanoclusters in an isotonic saline solution containing 0.02% tween-80. The procedure followed in preparation of this particle suspension is exactly the same in all studies presented in this manuscript. This figure demonstrates that the particles exist as singlets without aggregation.