Based on resonance scattering (RS) effect of rhodamine dye association particles, a new resonance scattering method for the determination of hydroxyl free radical from Fenton reaction was developed. In HCl-NaAc buffer solution, the OH of Fenton reaction oxidized the excess I(-) to I(3)(-). The I(3)(-) combined, respectively, with rhodamine B (RhB), butyl rhodamine B (b-RhB), rhodamine 6G (RhG) and rhodamine S (RhS) to form association particles that exhibit stronger resonance scattering effect at 420nm and 610nm. However, the RS peak at about 610nm was interfered with its synchronous fluorescence peak at 580nm for RhB, 580nm for b-RhB, 560nm for RhG and 560nm for RhS, respectively. The concentration of H(2)O(2) in the range of 0.648-21.6mumol/L, 0.423-13.0mumol/L, 0.216-13.0mumol/L and 0.092-13.0mumol/L was linear to its resonance scattering intensity at 420nm. Its detection limit was 0.15mumol/L, 0.10mumol/L, 0.092mumol/L and 0.044mumol/L, H(2)O(2), respectively. This RhS RS method was applied to selection of the antioxidant, with satisfactory results.
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http://dx.doi.org/10.1016/j.talanta.2006.03.002 | DOI Listing |
Talanta
January 2025
MOE Key Laboratory for Analytical Science of Food Safety and Biology, College of Chemistry, Fuzhou University, Fuzhou, China. Electronic address:
The current surface-enhanced Raman scattering (SERS) substrates typically feature a single energy level, posing challenges in coordinating electromagnetic enhancement (EM) and chemical enhancement (CM), thereby limiting the sensitive detection of numerous crucial target molecules. In this study, novel aggregated nanorings (a-NRs) hybridizing Ag, Au and AgCl are constructed as SERS substrates. On one hand, the obtained a-NRs exhibit robust localized surface plasmon resonance absorption, whose wavelength can be tuned to match three commonly used laser wavelengths (532, 633 and 785 nm) to gain strong EM effect.
View Article and Find Full Text PDFBioorg Chem
December 2024
Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Medicinal Chemistry, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address:
In this study, novel 2-styrylquinoline derivatives possessing a planar aromatic system and a flexible side chain with an amino substituent were designed and synthesized as DNA-intercalating antitumor agents. The cytotoxic activity of the synthesized compounds was evaluated against four cancer cell lines including MCF-7 (breast cancer cells), A549 (lung epithelial cancer cells), HCT116 (colon cancer cells) and normal cell line L929 (mouse fibroblast cell line). The results displayed that the anti-cancer activity of the target quinolines is sensitive to the lipophilic nature of the C-6 and C-7 quinoline substituents.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
USC Keck School of Medicine, Los Angeles, CA, USA.
Background: Human Apolipoprotein (APOE) has three isoforms, ε2, ε3, and ε4 among which ε4 (APOE4) confers the highest risk for late-onset Alzheimer's disease (AD). APOE4 is also the most prone to aggregate among APOE isoforms. Current evidence strongly suggests that APOE aggregation leads to neuronal dysfunction and eventually to AD.
View Article and Find Full Text PDFNano Lett
January 2025
University of Science & Technology of China, Hefei, Anhui 230026, China.
Metallic oxide can induce localized surface plasmon resonance (LSPR) through creating vacancies, which effectively achieve high carrier concentrations and offer advantages such as versatility and tunability. However, vacancies are typically created by altering the stoichiometric ratio of elements through doping, and it is challenging to achieve LSPR enhancement in the visible spectral range. Here, we have assembled CuO-superlattices to induce a high concentration of oxygen vacancies, resulting in LSPR within the visible spectrum.
View Article and Find Full Text PDFNat Commun
January 2025
Department of Physics and Arnold Sommerfeld Center for Theoretical Physics (ASC), Ludwig-Maximilians-Universität München, München, Germany.
Resonant interactions associated with the emergence of a bound state constitute one of the cornerstones of modern many-body physics. Here we present a Feshbach perspective on the origin of strong pairing in Fermi-Hubbard type models. We perform a theoretical analysis of interactions between spin-polaron charge carriers in doped Mott insulators, modeled by a near-resonant two-channel scattering problem, and report evidence for Feshbach-type interactions in the channel, consistent with the established phenomenology of cuprates.
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