The nanoparticle of claim 29, wherein the capping agent is represented by the general formula: (R)n???X wherein X is an atom or functional group capable of binding to the surface of the composition; and wherein R is hydrogen, an aryl group having between 1 and 10 carbon atoms, or an alkyl group having between 1 and 10 carbon atoms; n is an integer of at least 1. 37.