Functional Core-Shell Silica Particles

The chemistry of silica has been extensively studied over the centuries, for making glassware and optics, and more recently to create nano-sized particles.
We have recently developed methods to use organosilicate chemistry to synthesize particles with functional architectures for applications in nanobiotechnology and nanophotonics.
Using the Stöber sol-gel process, we can grow particles from tens of nm to microns in diameter, simply by varying the catalyst and precursor concentrations.

This control also allows us to grow core-shell particles with different components in the core and shell layers to make multi-functional materials.
References:
J. Choi, A. Burns, R. Williams, Z. Zhou, A. Flesken-Nikitin, W. Zipfel, U. Wiesner, A. Niktin. "Core-shell silica nanoparticles as fluorescent labels for nanomedicine" Journal of Biomedical Optics, 12(6) (2007) 064007-(1-11)

All images and text Copyright 2007
Wiesner Research Group - Cornell University
A. Burns H. Ow, U. Wiesner. "Fluorescent core-shell silica nanoparticles: towards 'Lab on a particle' architectures for nanobiotechnology" Chemical Society Reviews, 35, 2006, 1028-1042
H. Ow, D. Larson, M. Srivastava, B. Baird, W. Webb, U. Wiesner,"Bright and Stable Core-Shell Fluorescent Silica Nanoparticles", Nano Letters 5(1), 2005, 113-117
W. Stöber, et al. J. Coll. Int. Sci. 26, 62 (1968)
R. Iler, The Chemistry of Silica , Wiley Interscience, 1979