This paper presents results from the European Commission-funded project Doncalibrant, the objective of which was to produce calibrators with certified mass fractions of the Fusarium toxins deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-Ac-DON), 15-acetyldeoxynivalenol (15-Ac-DON), and nivalenol (NIV), in acetonitrile. The calibrators, available in ampoules, were sufficiently homogeneous, with between-bottle variations (s (bb)) of less than 2%. Long-term stability studies performed at four different temperatures between -18 and 40 degrees C revealed no significant negative trends (at a confidence level of 95%). Molar absorptivity coefficients (in L mol(-1) cm(-1)) were determined for all four toxins (DON: 6805 +/- 126, NIV: 6955 +/- 205, 3-Ac-DON: 6983 +/- 141, 15-Ac-DON: 6935 +/- 142) on the basis of a mini-interlaboratory exercise. The overall uncertainty of the calibrators' target values for DON and NIV were evaluated on the basis of gravimetric preparation data and include uncertainty contributions from possible heterogeneity, storage, and transport. The Doncalibrant project resulted in the production of calibrators for DON (IRMM-315) and NIV (IRMM-316) in acetonitrile with certified mass fractions of 25.1 +/- 1.2 microg g(-1) and 24.0 +/- 1.1 microg g(-1), respectively. Both CRMs became commercially available from the Institute for Reference Materials and Measurements (IRMM, Geel, Belgium) at the beginning of 2007.
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J Phys Chem A
January 2025
Department of Chemistry and Dodd Walls Centre, University of Otago, Dunedin 9016, New Zealand.
Three triphenylamine-Indane donor-acceptor dyes with different functional groups on the acceptor were studied to investigate how substitution would affect the optical properties. The dyes studied were IndCN, containing two malononitrile groups; InO, with two ketone groups; and InOCN, which features mixed functional groups. A combination of Raman spectroscopy, UV-vis absorption and emission spectroscopy, and density functional theory (DFT) calculations were employed for characterization.
View Article and Find Full Text PDFBiomaterials
January 2025
Center for AIE Research, Guangdong Provincial Key Laboratory of New Energy Materials Service Safety, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China; School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen (CUHK-Shenzhen), Guangdong, 518172, China. Electronic address:
Multimodal phototheranostics on the basis of single molecular species shows inexhaustible and vigorous vitality, particularly those emit fluorescence in the second near-infrared window (NIR-II), the construction of such exceptional molecules nonetheless retains formidably challenging. In view of the undiversified molecular skeletons and insufficient phototheranostic outputs of previously reported NIR-II fluorophores, herein, electron acceptor engineering based on heteroatom-inserted rigid-planar pyrazinoquinoxaline was manipulated to fabricate aggregation-induced emission (AIE)-featured NIR-II counterparts with donor-acceptor-donor (D-A-D) architecture. Systematical investigations substantiated that one of those synthesized AIE molecules, namely 4TPQ, incorporating a fused thiophene acceptor, synchronously exhibited high molar absorptivity (ε), NIR-II emission, typical AIE tendency, significant reactive oxygen species (ROS) generation, and high photothermal conversion efficiency.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Department of Chemistry, The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Division of Life Science, State Key Laboratory of Molecular Neuroscience, and Department of Chemical & Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China.
The two contradictory entities in nature often follow the principle of unity of opposites, leading to optimal overall performance. Particularly, aggregation-induced emission luminogens (AIEgens) with donor-acceptor (D-A) structures exhibit tunable optical properties and versatile functionalities, offering significant potential to revolutionize cancer treatment. However, trapped by low molar absorptivity (ε) owing to the distorted configurations, the ceilings of their photon-harvesting capability and the corresponding phototheranostic performance still fall short.
View Article and Find Full Text PDFJ Chem Eng Data
January 2025
Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim N-7491, Norway.
Densities and viscosities of aqueous 2-amino-2-methyl-1-propanol (AMP)/piperazine (PZ) solutions with and without CO are measured from 20 to 80 °C at ambient pressure. Redlich-Kister-based correlations are proposed for the excess molar volumes and viscosity deviation of the binary and ternary mixtures. Empirical correlations are developed to quantitatively describe the effect of CO on the density and viscosity of the aqueous AMP/PZ solutions.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China.
The elevated glutathione (GSH) level and hypoxia in tumor cells are two key obstacles to realizing the high performance of phototherapy. Herein, the electron-donating rotors are introduced to wings of electron-withdrawing pyrrolopyrrole cyanine (PPCy) to form donor-acceptor-donor structure -aggregates for amplified superoxide radical generation, GSH depletion, and photothermal action for hypoxic cancer phototherapy to tackle this challenge. Three PPCy photosensitizers (PPCy-H, PPCy-Br, and PPCy-TPE) produce hydroxyl radicals (•OH) and superoxide radicals (O) in hypoxia tumors exclusively as well as excellent photothermal performances under light irradiation.
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