Non-targeted analysis (NTA) is commonly used for the detection and identification of emerging pollutants, including many per- and polyfluoroalkyl substances (PFAS). While NTA outputs are often non-quantitative, concentration estimation is now possible using quantitative non-targeted analysis (qNTA) approaches. To date, few studies have examined matrix effects on qNTA performance, and little is therefore known about the implications of matrix effects on qNTA results and interpretations.
View Article and Find Full Text PDFThe US Environmental Protection Agency (EPA) uses non-targeted analysis (NTA) to characterize potential risks associated with environmental pollutants and anthropogenic materials. NTA is used throughout EPA's Office of Research and Development (ORD) to support the needs of states, tribes, EPA regions, EPA program offices, and other outside partners. NTA methods are complex and conducted via myriad instrumental platforms and software products.
View Article and Find Full Text PDFSolvatofluorochromic molecules provide strikingly high fluorescent outputs to monitor a wide range of biological, environmental, or materials-related sensing processes. Here, thiazolo[5,4-d]thiazole (TTz) fluorophores equipped with simple alkylamino and nitrophenyl substituents for solid-state, high-performance chemo-responsive sensing applications are reported. Nitroaromatic substituents are known to strongly quench dye fluorescence, however, the TTz core subtly modulates intramolecular charge transfer (ICT) enabling strong, locally excited-state fluorescence in non-polar conditions.
View Article and Find Full Text PDFA family of asymmetric thiazolo[5,4-]thiazole (TTz) fluorescent dye sensors has been developed, and their photophysical sensing properties are reported. The π-conjugated, TTz-bridged compounds are synthesized via a single-step, double condensation/oxidation of dithiooxamide and two different aromatic aldehydes: one with strong electron-donating characteristics and one with strong electron-accepting characteristics. The four reported dyes include electron-donating moieties (,-dibutylaniline and ,-diphenylaniline) matched with three different electron-accepting moieties (pyridine, benzoic acid, and carboxaldehyde).
View Article and Find Full Text PDFPhotoinduced electron and energy transfer through preorganized chromophore, donor, and acceptor arrays are key to light-harvesting capabilities of photosynthetic plants and bacteria. Mimicking the design principles of natural photosystems, we constructed a new luminescent pillared paddle wheel metal-organic framework (MOF), Zn(NDC)(DPTTZ), featuring naphthalene dicarboxylate (NDC) struts that served as antenna chromophores and energy donors and ,-di(4-pyridyl)thiazolo-[5,4-]thiazole (DPTTZ) pillars as complementary energy acceptors and light emitters. Highly ordered arrangement and good overlap between the emission and absorption spectra of these two complementary energy donor and acceptor units enabled ligand-to-ligand Förster resonance energy transfer, allowing the MOF to display exclusively DPTTZ-centric blue emission (410 nm) regardless of the excitation of either chromophore at different wavelengths.
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