The water-soluble bimetallic ultrasmall Co-Ni nanoclusters (Co-NiNCs) have been synthesized and characterize in different analytical approaches such as optical, thermal, antibacterial and bioinformatic studies. The as synthesized Co-NiNCs exhibited a pronounced absorption band at 341 nm in the UV-Vis spectrum, attributed to metal-to-ligand charge transfer and interband d-d electronic transitions, thereby consistent with quantum confinement effects and formation of ultrasmall bimetallic nanoclusters. Furthermore, Tauc plot analysis revealed dual optical band gaps of 2.88 and 3.88 eV, signifying tunable semiconducting characteristics with multiple electronic transition pathways induced by nanoscale confinement and synergistic Co-Ni electronic interactions. The TGA analysis confirms high thermal stability, presenting an similar to 80% weight loss due to the decomposition of organic ligands and stabilization above 450 degrees C. Antibacterial assays using E. coli showed a clear dose dependent growth inhibition comparable to a standard antibiotic. The molecular docking studies where there are favorable interactions of the ligand-modified nanoclusters and active sites of bacterial protein stabilized by hydrogen bonding, pi-pi stacking and van der Waals interactions. Based on the collective properties and the docking score is -7.8 kcal/mol, thiol-stabilized Co-NiNCs suggest potential applicability for both optoelectronic and potential biomedical applications.
Efficient chemotherapy drug delivery remains a major challenge in cancer treatment, requiring carriers that optimize adsorption, diffusion, and controlled release. In this study, molecular dynamics simulation was used to investigate the diffusion and accumulation of three chemotherapy agents-5-fluorouracil (5-FU), gemcitabine (GEM), and curcumin (CUR)-within four zirconium-based metal-organic frameworks (MOFs): UiO-66, UiO-67, UiO-68, and MOF-1004. Analysis of mean square displacements, diffusion coefficients, radial distribution functions, and concentration profiles revealed that UiO-66 shows the nearest distance loading of 5-FU, attributed to its optimal pore size, strong electrostatic interactions, and weakest drug & mldr;drug interaction. Meanwhile, MOF-1004 enhances the diffusion of CUR through the pores due to the larger pores and weaker binding energy. Pair correlation functions indicate that CUR tends to aggregate and interacts least with water-except in MOF-1004. Drug & mldr;MOF interactions are observed beyond 5 & Aring; from the MOF core, with 5-FU exhibiting the strongest interaction with MOF linkers. Electrostatic interactions primarily govern drug adsorption in UiO-type MOFs, while van der Waals forces dominate in MOFs with larger pores. These findings demonstrate the potential of structure-tailored MOFs for optimized drug delivery and provide a basis for future experimental validation and MOF design.
Fluorescent chemical sensors utilizing aggregation-induced emission (AIE) have emerged as powerful tools for monitoring metal ions relevant to biological and environmental contexts. This study reports the rational design and synthesis of a novel AIE-active luminophore, TPEBA, which is constructed via a Schiff base condensation reaction between 2-hydroxy-5-(1,2,2-triphenylethenyl)-benzaldehyde and 3,5-di-tert-butylaniline. TPEBA serves as a highly selective "turn-on" fluorescent probe for Zn2+ in an ethanol/PBS medium, exhibiting significant fluorescence enhancement and a pronounced blue shift (approximately 51 nm). The sensor achieves an exceptionally low detection limit of 78.3 nM, well below the World Health Organization's stipulated level, and enables rapid visual discrimination under ultraviolet light. By integrating spectroscopic techniques (Job's plot, FT-IR) with density functional theory (DFT) calculations, a 1:1 binding stoichiometry and a chelation-enhanced fluorescence (CHEF) mechanism are elucidated. The probe TPEBA exhibits excellent specificity, reversibility with EDTA, and successful applications in water quality analysis and test strips, highlighting its great application potential in practical environmental.
A new [Mg(OOC-(C6H4)2-COO)(H2O)4]n coordination polymer is synthesized under hydrothermal conditions. Spectroscopic and analytical methods (IR, single crystal X-ray, TGA/DTA) have allowed an accurate description. The titled compound crystallizes in monoclinic system. The combination of the octahedral metal environment and the bis-monodentate coordination mode of the diphenate ligand lead to 1D coordination polymer. The thermal behavior of [Mg(OOC-(C6H4)2-COO)(H2O)4]n studied by TGA/DTA give a detailed decomposition scheme with dehydration temperature, the stability range of the anhydrous complex and the expected MgO final product. A combined experimental and computational study was carried out to investigate the structural, vibrational, and electronic properties of the compound. The optimized geometry and FT-IR spectra were analyzed using DFT. For the electronic study, HOMO-LUMO calculations were performed on a protonated fragment preserving the octahedral environment around Mg(II) in order to obtain a closed-shell model. The HOMO-LUMO energy gap was found to be 4.536 eV. Hirshfeld surface, MEP, and RDG analyses were used to characterize intermolecular interactions. Molecular docking studies revealed a favorable binding affinity with the DNA gyrase B protein from Escherichia coli.
It is reported here the synthesis of a bioreactive polydenatate organo bis-dihydrazonylthiophene ligand (H2Lbthy), which was formed via a condensation reaction between thiophene-2,5-dicarboxylate and salicylaldehyde. Unlike previously reported organo-ligands, H2Lbthy enabled a strong coordination to iron(III) and vanadyl(IV) ions to form new metalated-complexes (FeLbthy and VOLbthy), whose structural and functional properties were systematically investigated. Remarkably, FeLbthy and VOLbthy complexes demonstrated significantly antimicrobial and anticancer activities compared to the free organo-ligand, as evidenced by reduced IC 50 values and increased inhibition zones against various human tumor cell lines and pathogenic microbes. Furthermore, this study uniquely elucidated the modulation of DNA binding affinity and thermodynamics (K b and Delta Gb not equal ) through metal complexation, revealing that iron(III) and vanadyl(IV) ions substantially augment the ligand's bioactivity via altered charge and coordination dynamics. Collectively, our findings introduced H2Lbthy-based metal complexes as promising candidates in the emerging field of metallodrugs, offering new avenues for the development of effective antimicrobial and anticancer agents.
