ANYL 74 |
| Capillary electrophoresis (CE) is a rapid and efficient technique for separation of a variety of compounds. Research in our laboratory has shown that cantilevered quartz nanopipettes can be used for Fountain Pen NanoLithography (FPN) with atomic force feedback of liquid phase chemicals such as etchants, proteins, etc. By combining these two techniques we can achieve the correlation of the separation of chemicals in time with spatially controlled nanodeposition to achieve Atomic Force Controlled Capillary Electrophoresis or ACCE. Here we demonstrate an electro-osmotic flow (EOF) in cantilevered quartz pipettes controlled by atomic force microscopic (AFM) techniques. Cantilevered nanopipettes with 0.1 - 0.5 micron aperture sizes are filled with a buffer and are brought with AFM control to a mica/Au surface. Subsequently, voltage pulses are applied between the gold substrate and the large end of the pipette to initiate the flow of buffer from the pipette to the substrate. A negative voltage on the substrate induces EOF when pH 8 buffer is used while pH 3 buffer neutralizes the quartz walls of the pipette and almost no EOF is observed. Initial experiments with proteins will also be described.
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General Posters
7:00 PM-9:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster
Sci-Mix
Division of Analytical Chemistry |