Interactions of pyrene-labeled silica particles

Silica spheres were prepared by the Stober method, and the method of labeli ng with pyrene, using aminopropylysilane as the linking agent, was optimize d. Excimers between particles were formed when high concentrations of label were used. Both surfactant and polyelectrolyte addition were able to cause hoc formation when added to suspensions of the silica, but only the surfac tant changed the I-1/I-3 ratio and diminished excimer formation. (C) 2000 A cademic Press.