Over the last decade, the miniaturization of analytical systems has become
an increasingly important and interesting research area. Miniaturized systems offer
many advantages, including reduced reagent and sample consumption, shorter
analysis times, portability and disposability. This dissertation describes novel
approaches in this direction, focusing on two areas: the miniaturization of existing
column chromatographic systems and the development of microfluidic systems in
which the separation is performed in a channel on a microchip.
A new type of methacrylate-based monolithic capillary columns for liquid
chromatography and capillary electrochromatography were prepared within the
confines of fused-silica tubing using Starburst dendrimers to affect porosity.
The polyamidoamine (PAMAM) dendrimers were incorporated into a solution of
functionalized monomer, cross-linker, solvents, and polymerization initiator.
Thermal polymerization, followed by the removal of solvent and dendrimers,
produced a continuous rod of polymer with uniform porosity. Different column
porosities were obtained by varying the amount of the dendrimer template. The
chromatographic performance of these monolithic columns was evaluated using a
peptides mixture obtained by tryptic digestion of chicken egg lysozyme.
A distinct advantage of polymer monolithic stationary phases over
conventional packed chromatographic beds is the ability to prepare them easily and
rapidly via free radical polymerization within the channels of a microfluidic device.
In this work, continuous polymeric beds were prepared within a channel of
three different microchip substrates: glass, poly(dimethylsiloxane) and
polycarbonate. The methacrylate-based monolith was cast in-situ via UV-initiated
polymerization. The functionalization of the inner wall of the channel with
methacryloyl groups enabled the covalent binding of the monolith to the wall. The
morphology of the wall-anchored monolith was studied by SEM of chip sections,
and by SEM of an extruded segment of non-anchored monolith from a separate
chip. / Graduation date: 2005
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/29321 |
| Date | 28 April 2005 |
| Creators | Doneanu, Angela |
| Contributors | Remcho, Vincent T. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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