The flavonoids constitute a large group of polyphenolic phytochemicals with antioxidant properties in vitro. The interactions of four structurally related flavonoids (quercetin, kaempferol, rutin and luteolin) with Cu2+ ions were investigated in terms of the extent to which they undergo complex formation through chelation or modification through oxidation, as well as in their structural dependence. The ortho 3',4'-dihydroxy substitution in the B ring is shown to be important for Cu2+-chelate formation, thereby influencing the antioxidant activity. The presence of a 3-hydroxy group in the flavonoid structure enhances the oxidation of quercetin and kaempferol, whereas luteolin and rutin, each lacking the 3-hydroxy group, do not oxidize as readily in the presence of Cu2+ ions. The results also demonstrate that the reactivities of the flavonoids in protecting low-density lipoprotein (LDL) against Cu2+ ion-induced oxidation are dependent on their structural properties in terms of the response of the particular flavonoid to Cu2+ ions, whether chelation or oxidation, their partitioning abilities between the aqueous compartment and the lipophilic environment within the LDL particle, and their hydrogen-donating antioxidant properties.
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http://dx.doi.org/10.1042/bj3301173 | DOI Listing |
Luminescence
January 2025
Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, Assam, India.
The fused heterocycle 1-(imidazo[5,1-a]isoquinolin-3-yl)naphthalen-2-ol (LH) has been synthesized and characterized by spectroscopic methods. Probe LH upon irradiation with λ = 336 nm exhibited strong fluorescence with λ = 437 nm in MeOH/HEPES buffer (5 mM, pH = 7.4, 2:8, v/v).
View Article and Find Full Text PDFCarbohydr Polym
March 2025
College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China; School of Chemistry, Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, South China Normal University, Guangzhou 510006, China. Electronic address:
The management of wounds infected with drug-resistant bacteria represents a significant challenge to public health globally. Nanotechnology-functionalized photothermal hydrogel with good thermal stability, biocompatibility and tissue adhesion exhibits great potential in treating these infected wounds. Herein, a novel photothermal hydrogel (mCS-Cu-Ser) was prepared through in situ mineralization in the hydrogel networks and ion cross-linking driven by copper ions (∼3 mM).
View Article and Find Full Text PDFCarbohydr Polym
March 2025
Department of Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China. Electronic address:
Cuproptosis shows great prospects in cancer treatments. However, insufficient intracellular copper amount, low-level redox homeostasis, and hypoxic tumor microenvironment severely restrict cuproptosis efficacy. Herein, hydrazided hyaluronan-templated decorated CuO-doxorubicin (CuDT) nanodot clusters (NCs) are developed for efficient doxorubicin (DOX)-sensitized cuproptosis therapy in breast cancer via a three-pronged strategy.
View Article and Find Full Text PDFAnal Methods
January 2025
Department of Chemistry, Karpagam Academy of Higher Education, Coimbatore, Tamil Nadu, India.
A new rhodamine based turn on florescent probe ()-3',6'-bis(ethylamino)-2-(((6-methoxy-2-oxo-1,2-dihydroquinolin-3-yl)methylene)amino)-2',7'-dimethylspiro[isoindoline-1,9'-xanthen]-3-one (RME) was efficiently synthesized through a simple condensation reaction of 2-amino-3',6'-bis(ethylamino)-2',7'-dimethylspiro[isoindoline-1,9'-xanthen]-3-one and 6-methoxy-2-oxo-1,2-dihydroquinoline-3-carbaldehyde. The receptor RME is highly non-fluorescent and when copper ions (Cu ions) are added in DMF/water (1 : 2, v/v) medium, the receptor RME exhibits a specific "turn-on" colorimetric and fluorometric response. Moreover, RME binding with Cu ions produced a remarkable color variation that was perceptible to the human eye, changing from colorless to pink.
View Article and Find Full Text PDFCrit Rev Anal Chem
January 2025
Department of Oral & Maxillofacial Surgery and Diagnostic Sciences, Faculty of Dentistry, Taif University, Taif, Saudi Arabia.
Organic fluorescence and colorimetric probes have emerged as vital tools for detecting metal ions, due to their high sensitivity, selectivity, and rapid response times. Copper, an essential trace element, plays a critical role in biological systems, yet its imbalance can lead to severe disorders such as neurodegenerative diseases, cancer, and Wilson's disease. Over the past few years, advancements in probe design have unlocked innovative avenues for not only detecting Cu in environmental and biological samples but also for visualizing its distribution through fluorescence imaging.
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