I. Hadamard Transform Capillary Electrophoresis for the Analysis of Biologically Active Species II. Characterization and Application of Two-Photon Activatable Proton and Radical Generators

Persistent Link:
http://hdl.handle.net/10150/195135
Title:
I. Hadamard Transform Capillary Electrophoresis for the Analysis of Biologically Active Species II. Characterization and Application of Two-Photon Activatable Proton and Radical Generators
Author:
Braun, Kevin L
Issue Date:
2005
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
PART I. A modified Hadamard transform has been developed and applied to the analysis of biologically active species using capillary electrophoresis. Hadamard transformations, a matrix based multiplexing technique, when coupled with a capillary electrophoresis instrument capable of rapid sample injection, provides a means to semi-continuously inject samples. The multiple injections separate, interpenetrate, and are detected as the summation of the multiple injections. Deconvolution of the multiplexed signal by multiplication with the inverse of the injection matrix yields a single injection electropherogram that exhibits improved S/N. In modified Hadamard transform capillary electrophoresis (mHTCE), an injection sequence of half the length as conventional HTCE (cHTCE) is utilized. Modifying the manner in which the raw data is manipulated before deconvolution facilitates the reduced injection sequence. When coupled with software, mHTCE can reduce the collection time for a Hadamard sequence by up to 48%. The substantial time reduction afforded by mHTCE is utilized to demonstrate the first time-resolved application of Hadamard transformations for the analysis of neurotransmitters. Additionally, mHTCE has been demonstrated as a means to improve the sensitivity for analysis of amino acids and proteins including gamma-aminobutyric acid, dopamine, and enhanced green fluorescent protein (EGFP) with picomolar detection limits.Part II. Two-photon excitation provides a means to activate chemical and physical processes with high spatial resolution and improved depth penetration compared to one-photon excitation. When combined with three-dimensional lithographic microfabrication (3DLM), these advantages provide a means to fabricate complex structures through radical and cationic two-photon induced polymerization (TPIP). A strategy for realizing high-fidelity microstructures is reported that considers the inherent structural limitations of acrylate monomers. Utilizing this strategy, a series of high-fidelity microstructures is reported for application in microfluidic devices, microelectromechanical systems (MEMS), and microoptical devices such as photonic bandgap (PBG) crystals. Improved periodicity is reported here for f.c.c. PBG crystals compared to earlier examples through addition of micromechanical supports that provide increased strength to the high-aspect ratio crystals. To extend TPIP to cationic polymerization, a series of two-photon activatable photoacid generators has been developed. The new PAGs exhibit one to two orders of magnitude lower polymerization threshold intensities than conventional ultraviolet-sensitive initiators.
Type:
text; Electronic Dissertation
Keywords:
Capillary Electrophoresis; Hadamard Transform; Two-photon; Microlithography
Degree Name:
PhD
Degree Level:
doctoral
Degree Program:
Chemistry; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Aspinwall, Craig A.; Perry, Joseph W.
Committee Chair:
Aspinwall, Craig A.; Perry, Joseph W.

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleI. Hadamard Transform Capillary Electrophoresis for the Analysis of Biologically Active Species II. Characterization and Application of Two-Photon Activatable Proton and Radical Generatorsen_US
dc.creatorBraun, Kevin Len_US
dc.contributor.authorBraun, Kevin Len_US
dc.date.issued2005en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractPART I. A modified Hadamard transform has been developed and applied to the analysis of biologically active species using capillary electrophoresis. Hadamard transformations, a matrix based multiplexing technique, when coupled with a capillary electrophoresis instrument capable of rapid sample injection, provides a means to semi-continuously inject samples. The multiple injections separate, interpenetrate, and are detected as the summation of the multiple injections. Deconvolution of the multiplexed signal by multiplication with the inverse of the injection matrix yields a single injection electropherogram that exhibits improved S/N. In modified Hadamard transform capillary electrophoresis (mHTCE), an injection sequence of half the length as conventional HTCE (cHTCE) is utilized. Modifying the manner in which the raw data is manipulated before deconvolution facilitates the reduced injection sequence. When coupled with software, mHTCE can reduce the collection time for a Hadamard sequence by up to 48%. The substantial time reduction afforded by mHTCE is utilized to demonstrate the first time-resolved application of Hadamard transformations for the analysis of neurotransmitters. Additionally, mHTCE has been demonstrated as a means to improve the sensitivity for analysis of amino acids and proteins including gamma-aminobutyric acid, dopamine, and enhanced green fluorescent protein (EGFP) with picomolar detection limits.Part II. Two-photon excitation provides a means to activate chemical and physical processes with high spatial resolution and improved depth penetration compared to one-photon excitation. When combined with three-dimensional lithographic microfabrication (3DLM), these advantages provide a means to fabricate complex structures through radical and cationic two-photon induced polymerization (TPIP). A strategy for realizing high-fidelity microstructures is reported that considers the inherent structural limitations of acrylate monomers. Utilizing this strategy, a series of high-fidelity microstructures is reported for application in microfluidic devices, microelectromechanical systems (MEMS), and microoptical devices such as photonic bandgap (PBG) crystals. Improved periodicity is reported here for f.c.c. PBG crystals compared to earlier examples through addition of micromechanical supports that provide increased strength to the high-aspect ratio crystals. To extend TPIP to cationic polymerization, a series of two-photon activatable photoacid generators has been developed. The new PAGs exhibit one to two orders of magnitude lower polymerization threshold intensities than conventional ultraviolet-sensitive initiators.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectCapillary Electrophoresisen_US
dc.subjectHadamard Transformen_US
dc.subjectTwo-photonen_US
dc.subjectMicrolithographyen_US
thesis.degree.namePhDen_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineChemistryen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorAspinwall, Craig A.en_US
dc.contributor.advisorPerry, Joseph W.en_US
dc.contributor.chairAspinwall, Craig A.en_US
dc.contributor.chairPerry, Joseph W.en_US
dc.contributor.committeememberSanov, Andreien_US
dc.contributor.committeememberMcGrath, Dominic V.en_US
dc.contributor.committeememberMonti, Oliver L. A.en_US
dc.contributor.committeememberSaavedra, S. Scotten_US
dc.identifier.proquest1270en_US
dc.identifier.oclc137354728en_US
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