Chemistry Commons^™

Plant Stimuli-Responsive Biodegradable Polymers For The Use In Timed Release Fertilizer Coatings, Spencer Heuchan

Electronic Thesis and Dissertation Repository

The use of nitrogen-based fertilizers continues to accelerate with human population growth and increases in global food requirements. Enhanced efficiency fertilizers (EEFs) have been developed to improve the synchronization between nutrient supply and crop nutrient demand. However, many of the current controlled release fertilizers are coated with non-degradable polymers that contribute to accumulation of microplastics within ecosystems. This thesis describes research towards the development of a new class of fertilizer coatings using a self-immolative polymer known as poly (ethyl glyoxylate) (PEtG). PEtG itself does not have suitable properties to produce a viable coating but once blended with another degradable polyester …

Detection Of Amyloid Beta (Aβ) Oligomeric Composition Using Matrix-Assisted Laser Desorption Ionization Mass Spectrometry (Maldi Ms)., Jasmine S-H Wang, Shawn N Whitehead, Ken K-C Yeung

Chemistry Publications

The use of MALDI MS as a fast and direct method to detect the Aβ oligomers of different masses is examined in this paper. Experimental results suggest that Aβ oligomers are ionized and detected as singly charged ions, and thus, the resulting mass spectrum directly reports the oligomer size distribution. Validation experiments were performed to verify the MS data against artifacts. Mass spectra collected from modified Aβ peptides with different propensities for aggregation were compared. Generally, the relative intensities of multimers were higher from samples where oligomerization was expected to be more favorable, and vice versa. MALDI MS was also …

A Chimeric Nucleobase - Phenylazo Derivative As An Intrinsic Nucleobase Quencher, Gyeongsu Park, Timothy Martin-Chan, Amer El Samm, Robert H.E. Hudson

Western Research Forum

Molecular beacons are important bioanalytical probes which are most often

constructed from a single-stranded oligonucleotide which has been labeled at

opposite termini with a fluorophore and a quencher. When the fluorophore and

quencher are in close proximity, no fluorescence is observed due to FRET

(Fluorescence Resonance Energy Transfer). DABCYL (4-dimethylaminoazobenzene-

4'-carboxylic acid) has been used as a quencher in the molecular beacon to absorbs

excitation energy from a fluorophore and to dissipate the energy as heat. However,

DABCYL is unable to form a base-pair and is conventionally placed as an overhanging

residue. This produces a derivative wherein the chromophore has …