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Five Zn( [II)) and Cd(II) coordination complexes, [Zn(NA)2 (H2O)4](1), [Zn(INA)2 (H2O)4](2), [Zn(2,2'-bi-py)2 (SCN)2](3), [Cd(INA)2 (H2O)4](4) and [Cd(phen)2(NO3)](5) (HNA=nicotinic acid, HINA=isonicotinic acid, 2, 2'-bipy=2,2'-bipyridine, phen=1,10-phenanthroline), were synthesized through constant temperature magnetic stirrer or hydrothermal method, and their single-crystal structures were determined by X-ray diffraction. The authors measured the IR, UV-Vis-NIR and fluorescence spectra of the complexes and analyzed their photophysical properties. At room temperature in the solid state the five complexes can show strong fluorescence, i.e., lamdamax(em)=362 nm (lamda(ex)=330 nm), (1); lamdamax(em)=424 nm (lamda(ex)=330 nm), (2); lamdamax(em)=442 nm (lamda(ex)=380 nm), (3); lamdamax(em)=424 nm (lamda(ex)=330 nm), (4); lamda(em max)=456 nm (lamda(ex)=360 nm), (5), and complex (5) can emit phosphorescence upon excitation at 360 nm (lamdamax (pl)=546 nm, tau=10 ms). But the organic ligands are different, which lead to the luminescence property of complexes originating from different charge transfer. Compared with the relevant ligands (lamdamax (em)=380 nm, HNA; lamda(em max)=541 nm, 2,2'-bipy), the fluorescence emissions of complex (1) and (3) show a blue-shift which mainly comes from the ILCT (intraligand charge transfer) and at the same time exists L-->M(4S) transfer. The emissions of complex (2) and (4) come from LMCT (ligand-to-metal charge transfer) and show red-shift compared to that of free ligand (lamdamax(em)=337 nm, HINA). For complex (5), the appearance and position of its emission are different from those of the ligand (lamdamax(em)=381 nm, phen), which is attributed to LLCT (ligand-to-ligand charge transfer) and LMCT.
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FEBS J
September 2025
Neutron Scattering Division, Oak Ridge National Laboratory, USA.
Serine hydroxymethyltransferase (SHMT) is a critical enzyme in the one-carbon (1C) metabolism pathway catalyzing the reversible conversion of L-Ser into Gly and concurrent transfer of 1C unit to tetrahydrofolate (THF) to give 5,10-methylene-THF (5,10-MTHF), which is used in the downstream syntheses of biomolecules critical for cell proliferation. The cellular 1C metabolism is hijacked by many cancer types to support cancer cell proliferation, making SHMT a promising target for the design and development of novel small-molecule antimetabolite chemotherapies. To advance structure-assisted drug design, knowledge of SHMT catalysis is crucial, but can only be fully realized when the atomic details of each reaction step governed by the acid-base catalysis are elucidated by visualizing active site hydrogen atoms.
View Article and Find Full Text PDFAnal Chim Acta
November 2025
School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, PR China. Electronic address:
Background: Daminozide is a commonly utilized plant growth regulator. Both daminozide and its hydrolysis product, 1,1-dimethyl hydrazine ((CH)NNH), exhibit carcinogenic and teratogenic toxicity. Accurate detection of daminozide in food is of great significance to human health.
View Article and Find Full Text PDFFertil Steril
September 2025
REI Division, Department of Obstetrics and Gynecology, University of Iowa Hospitals and Clinics, Carver College of Medicine, Iowa City. Iowa. 52242.
Objective: To investigate the impact of objectively measured physical activity and stress on programmed hormone replacement therapy (HRT) frozen embryo transfer (FET) outcomes.
Design: Observational cohort study SUBJECTS: Patients undergoing standard HRT FET at a single academic center.
Exposure: Average daily step counts before and after FET as measured by FitBit Charge 5 wearable activity tracker.
Int J Biol Macromol
September 2025
Crystal Growth Centre, Anna University, Chennai, 600025, Tamil Nadu, India.
Increase in breast cancer has led to the search for systems that can enable, targeted, sustained and prolonged release of drugs while simultaneously reducing the side effects posed by them. In light of this, folic acid-conjugated 5-Fluorouracil and doxorubicin loaded chitosan/Fe₃O₄ (FA-dual@CS/Fe₃O₄) nanocomposite has been synthesized using the chemical method for targeted breast cancer therapy in addition to CS/FeO and dual drug encapsulated CS/FeO. FTIR and XPS studies confirm the successful drug encapsulation and FA conjugation.
View Article and Find Full Text PDFWater Res
September 2025
Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China.
The advanced degradation of ferricyanide ([Fe(CN)₆]³⁻) in industrial wastewater faces dual bottlenecks of self-acidification-induced hydrogen cyanide (HCN) release and inefficient decomplexation. This study innovatively constructs an alkaline UV/Peracetic Acid (PAA) synergistic system and systematically elucidates its triple action mechanism: (1) UV irradiation at 254 nm directly drives ligand-to-metal charge transfer (LMCT) excitation of ferricyanide, achieving efficient Fe-CN bond breaking (Φ₂₅₄ = 0.235-0.
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