Thursday, September 25, 2008 - 11:25 AM
Capri 114 (Riviera Hotel and Convention Center)

High-Speed Separations Inside Capillaries Packed with Silica Colloidal Crystals

Douglas S. Malkin, Jill M. Uhlenkamp, and Mary J. Wirth. University of Arizona, Tucson, AZ

Crystals made from 300, 500 and 800 nm silica nanoparticles are packed into 100 micron I.D. capillaries and chemically modified with a variety of silanes for use in pressure and electrically driven separations. Reverse phase separations have been performed in a capillary packed with 300 nm silica nanoparticles modified with C18 or C4. The results from the reverse phase separations show at least 10-fold smaller plate heights than those for a conventional HPLC column. Isoelectric focusing of the three BSA isoforms have been observed in a capillary packed with 800 nm silica nanoparticles modified with polyacrylamide using ATRP. Hydrodynamic chromatography is also being investigated in capillaries packed with 300 and 500 nm silica nanoparticles modified with Polyethylene Glycol or methyltrichlorosilane. The results show that these media are promising for high-speed separations and multi-dimensional separations.