Doctor of Philosophy (PhD)
Molecularly Imprinted Polymers (MIPs) encompass a wide range of applications by changing the different components, e.g. the template, crosslinker or functional monomers. Of interest among these different applications are separations and sensors. Separations by MIPs traditionally use a chiral pure template but in some cases that chiral pure template may not be available for imprinting. Using chiral (N-α-bismethacyloyl-L-alanine) and achiral (N,O-bisacrylamide ethanolamine) crosslinkers we investigated imprinting of scalemic and racemic template mixtures of Boc-tyrosine enantiomers. The achiral and chiral crosslinkers yielded similar results for the partial separation of enantiomers by scalemic imprinted polymers because separation and recognition are not dependent on diastereomeric interactions here. The racemic imprinted polymers, however, required the chiral crosslinker for chiral differentiation. Surprisingly, variable D or L bias was observed in the L-NALA racemic imprints with equal probability over multiple replicates of polymer synthesis. The binding of the template to the polymer was evaluated in both batch rebinding and chromatographic modes, and the results will be discussed in detail. Another important area of MIPs is their applicability in sensor devices, especially for biological targets. A proven method of development of a sensor by molecular imprinting is by incorporating MIPs in a stimuli-responsive hydrogel. An imprinted hydrogel was developed to detect a DNA mir21 mimic using complementary aptamers in both a capillary hydrogel format and thin film hydrogel diffraction grating. The hydrogels imprinted for the DNA mir21 target were responsive to the re-introduction of the target sequence and selective among similar nucleotide sequences. It was also shown that an imprinted system was required; the pre-polymer complex of both the aptamers with the DNA mir21 mimic was necessary to achieve maximum stimuli response detected by shrinking of the hydrogel sensor.
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Hebert, Britney Lyn, "Molecularly Imprinted Polymers for Enantiomer Separations and Biomolecular Sensors" (2016). LSU Doctoral Dissertations. 2941.