Session: Undergraduate Research Posters: Polymer Chemistry:

Signal amplification performs a crucial role in a detection assay by producing a detectable readout of analyte presence in a short time period. Quick and efficient amplification can be accomplished using a polymerization reaction, which amplifies a signal by inciting the formation of a long polymer off of a single initiator molecule. Previous research in our lab has led to the development of a novel detection assay using an aqueous atom transfer radical polymerization (ATRP) reaction. This assay provides real-time readouts of polymerization progress by using fluorogenic monomers—monomers that are dark in their monomer form but fluoresce under UV light when incorporated into a polymer—to couple the presence of analyte to fluorescence in solution. Though encouraging, the practicality of the originally reported assay was limited by long reaction times and oxygen intolerability. In order to further develop this assay for optimized capabilities of detection, it was necessary to manipulate the reaction to achieve the maximum fluorescence possible in the shortest time.
Several reaction variables were analyzed and modified to examine their effects on fluorescence and reaction kinetics. Elements of the reaction’s catalysis system were probed to balance an increase in reaction rate with a decrease in control over fluorescence. Different surfactants and solvents were screened for their abilities to increase fluorescence and speed and to reduce variability. Methods of reducing the effects of oxygen on the polymerization were explored. The characteristics of the reaction created by the combination of the optimized components were examined and compared to the original conditions, offering insights into how different components affect the total reaction, as well as pointing to potential future applications for the assay.

Comparison of original and optimized fluorogenic ATRP conditions. a) Maximum fluorescence emission at 426 nm over time. b) Photographs of reactions at select timepoints illuminated by UV light (365 nm).

Comparison of original and optimized fluorogenic ATRP conditions. a) Maximum fluorescence emission at 426 nm over time. b) Photographs of reactions at select timepoints illuminated by UV light (365 nm).

Christina Cooley

Trinity University

Appearances