Rubrene crystallization in 3-D focusing microfluidic devices

CHED 278

Callie A. Croushore, croushca@westminster.edu, Department of Chemistry, Westminster College, Box 637 Westminster College, 319 South Market Street, New Wilmington, PA 16172 and Valerie Genot, Laboratory of Supramolecular and Macromolecular Photophysics and Photochemistry, Ecole Normale Superieure de Cachan, PPSM UMR 8531 CNRS, 61, avenue du President Wilson, 94235 Cachan.
Microfluidics allows to study reaction conditions and behavior of nano- and micro-liter sized solutions. We have studied microsystems designed for the synthesis of organic nanocrystals of rubrene via non solvent crystallization. Experiments were performed using T or Y-type micro-channel moulded in PDMS (polydimethylsiloxene), bonded on a glass substrate, and observed under a microscope. The efficiency and reproducibility of the synthesis was tested using several 3D focusing microfluidic device designs. The most efficient microdevices were used to produce rubrene crystals under several non-solvent (water and surfactant) side and capillary (rubrene solution in THF and Ethanol) flow rates. By varying the side and capillary flow rates, we changed the mixing and reacting conditions, and hence the manner of obtaining supersaturation. Rubrene crystal suspensions were characterized using Dynamic Light Scattering and Fluorescence. Results suggest that flow rates and design of the microdevice affect the size distribution and quenching properties of the rubrene crystals.
 

Undergraduate Research Poster Session: Analytical Chemistry
11:00 AM-1:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Poster

Division of Chemical Education

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008