DEVELOPMENT OF SOLID SUBSTRATE LUMINESCENCE AND CHROMATOGRAPHIC TECHNIQUES FOR CHEMICAL ANALYSIS

Room Temperature Phosphorimetry (RTP) is a sensitive and selective technique which is well suited to the analysis of compounds of environmental and pharmaceutical interests. Absolute sensitivity is generally in the low to subnanograrn range. Selectivity of this technique is due to the fact that only several hundred compounds phosphoresce at room temperature. In these studies attempts are made to gain a greater understanding of the phenomenon of solid substrate room temperature phosphorimetry and to extend the application range of the technique. This goal is approached through several directions, all leading to a greater understanding of solid substrate luminescence in general, and in specific, Room Temperature Phosphorimetry. High Performance Thin Layer Chromatography (HPTLC) plates are evaluated as solid substrates for RTP. This yields the immediate benefit of a new and useful solid substrate for the analysis of ionic compounds. In addition a mechanism for RTP enhancement of ionic compounds and Polycyclic Aromatic Hydrocarbons (PAH) compounds is discussed. The extension of the application range of RTP is approached by introducing derivatization reagents. By using fluorescamine, the application range of RTP is extended to include all primary amines. An investigation is carried out to determine limits of detection of various amino acids in laboratory prepared solutions. In addition, the technique is extended to include phosphorescent and non-phosphorescent pharmaceutical compounds, concluding with a real sample determination of phenylpropanolamine in diet capsules. The development of a solid substrate luminescence detector for liquid chromatography also extends the application range of RTP. By developing such instrumentation, selectivity of both Room Temperature Phosphorescence and Fluorescence (RTP and RTF) and Liquid Chromatography (LC) can be employed together to minimize the amount of time needed for analysis. In addition, concentrating power of liquid chromatography can be employed in the analysis of more dilute solutions of analyte, in situations where sample volume is not a concern. Lastly, solid substrate luminescence of pharmaceutical materials in tablet form is discussed. This investigation shows the feasibility of using Solid Substrate Luminescence techniques to analyze active ingredients in pharmaceutical preparations. In this study, propranolol, para amino benzoic acid and acetylsalicylic acid are used as model compounds to determine the feasibility of nearly non-destructive analysis using Solid Substrate Luminescence

A Buddhist Approach to International Relations

This book is an open access book. Many scholars have wondered if a non-Western theory of international politics founded on different premises, be it from Asia or from the “Global South,” could release international relations from the grip of a Western, “Westphalian” model. This book argues that a Buddhist approach to international relations could provide a genuine alternative. Because of its distinctive philosophical positions and its unique understanding of reality, human nature and political behavior, a Buddhist theory of IR offers a way out of this dilemma, a means for transcending the Westphalian predicament. The author explains this Buddhist IR model, beginning with its philosophical foundations up through its ideas about politics, economics and statecraft

Dust in a Type Ia Supernova Progenitor: Spitzer Spectroscopy of Kepler's Supernova Remnant

Characterization of the relatively poorly-understood progenitor systems of Type Ia supernovae is of great importance in astrophysics, particularly given the important cosmological role that these supernovae play. Kepler's Supernova Remnant, the result of a Type Ia supernova, shows evidence for an interaction with a dense circumstellar medium (CSM), suggesting a single-degenerate progenitor system. We present 7.5-38 $\mu$m infrared (IR) spectra of the remnant, obtained with the {\it Spitzer Space Telescope}, dominated by emission from warm dust. Broad spectral features at 10 and 18 $\mu$m, consistent with various silicate particles, are seen throughout. These silicates were likely formed in the stellar outflow from the progenitor system during the AGB stage of evolution, and imply an oxygen-rich chemistry. In addition to silicate dust, a second component, possibly carbonaceous dust, is necessary to account for the short-wavelength IRS and IRAC data. This could imply a mixed chemistry in the atmosphere of the progenitor system. However, non-spherical metallic iron inclusions within silicate grains provide an alternative solution. Models of collisionally-heated dust emission from fast shocks ($>$ 1000 km s$^{-1}$) propagating into the CSM can reproduce the majority of the emission associated with non-radiative filaments, where dust temperatures are $\sim 80-100$ K, but fail to account for the highest temperatures detected, in excess of 150 K. We find that slower shocks (a few hundred km s$^{-1}$) into moderate density material ($n_{0} \sim 50-250$ cm$^{-3}$) are the only viable source of heating for this hottest dust. We confirm the finding of an overall density gradient, with densities in the north being an order of magnitude greater than those in the south.Comment: Accepted by ApJ. 11 pages, 5 figures, 1 table. Produced using emulateapj forma

⁹⁹ᵐTc SPECT imaging agent based on cFLFLFK for the detection of FPR1 in inflammation

Non-invasive imaging of the inflammatory process can provide a great deal of insight into a wide variety of diseases states, aiding diagnosis, evaluation and effective targeted treatment. During inflammation, blood borne leukocytes are recruited, through a series of activation and adhesion steps, to the site of injury or infection where they migrate across the blood vessel wall into the tissue. Thus, tracking leukocyte recruitment and accumulation provides a dynamic and localised read out of inflammatory events. Current leukocyte imaging techniques require ex vivo labelling of patient blood, involving laborious processing and potential risks to both patient and laboratory staff. Utilising high affinity ligands for leukocyte specific receptors may allow for injectable tracers that label leukocytes in situ, omitting potentially hazardous ex vivo handling. Formyl peptide receptors (FPRs) are a group of G-protein coupled receptors involved in the chemotaxis and inflammatory functioning of leukocytes. Highly expressed on leukocytes, and up regulated during inflammation, these receptors provide a potential target for imaging inflammatory events. Herein we present the synthesis and initial in vitro testing of a potential Single Photon Emission Computed Tomography (SPECT) leukocyte tracer. The FPR1 antagonist cFLFLFK-NH₂, which displays high affinity with little physiological effect, has been linked via a PEG motif to a ⁹⁹ᵐTc chelate. This tracer shows in vitro binding to human embryonic kidney cells expressing the FPR1 receptor, and functional in vitro tests reveal cFLFLFK-NH₂ compounds to have no effect on inflammatory cell functioning. Overall, these data show that ⁹⁹ᵐTc.cFLFLFK-NH₂ may be a useful tool for non-invasive imaging of leukocyte accumulation in inflammatory disease states