1. Keith Johnston Research Group Email: kpj@che.utexas.edu Synthesis and Assembly of Nanocrystals with Supercritical Fluids –Assembly on unpatterned and patterned substrates –Si and Ge nanocrystals, nanowires (high T) Controlled release of nanoparticle pharmaceuticals (oral, depot, pulmonary) –Poorly water soluble drugs –Peptides and proteins- (stability and release)

2. Fast Nanocrystal Evaporation w/o Dewetting Lin et al. J. Phys. Chem. B, 2001. Ag/FOMA/CO2 Control supersaturation during evaporation of liq. CO2 Shah et al. 2003

3. Nanocrystal Assembly on Surfaces 1. Nanocoatings 2. Photonic crystals 3. Inverse opals 4. Patterned structures 5. Microwires 6. Nanodevices

4. A B Significant blue-shift compared to bulk silicon band gap Discrete features in PLE spectra Room T quantum yield of 23% Size dependent luminescence UV, green light- displays/sensors Future- control size, yield, contamination, measure optoelectronic properties Silicon PLE and PL (Ge also)

5. High Dissolution Rates for Poorly Water Soluble Drug Nanoparticles Solution based nucleation –Antisolvent (2 processes) –Evaporation –freezing (2 processes) Control nucleation, growth and stabilization Animal tests- bioavailability 2 nm danazol domains mixed with PVP (spray freezing) www.bioaqueous.com (Dow Chemical)

6. Nanostructured particles by rapid nucleation and surfactant stabilization Interface orients surfactant High surface area, wettability, dissol. rates and bioavailability High drug:surfactant ratios

7. Destination of PhD Students DixonS. Dakota S. Mines Gupta Auburn Balbuena U. S. Carol. Luna-Barcenas CINVESTAV Res. Inst. MeredithGa. Tech. YatesU. Rochester Da RochaWayne State U. LeeU. S. California McFannUnilever Condo3M HarrisonTI MawsonUnion Carbide Li*Cardinal Health YoungDow (Pharma) PsathasSchering-Plough RogersDow (Pharma) SirardLam Research