Search Results (178)

Damage to urban water supply infrastructure can rapidly compromise access to safe water and force households to rely on alternative sources of uncertain quality. This study presents a case-based assessment of water quality and emergency household-level treatment options in Mykolaiv, Ukraine, following conflict-induced disruption of the centralized water supply system. Water samples collected from selected groundwater and distribution-network points were analyzed for physicochemical, organoleptic, and microbiological indicators, including total dissolved solids, hardness, sulfates, chlorides, iron, permanganate oxidizability, total microbial count, and E. coli. The results showed elevated mineralization, increased sulfate and chloride concentrations, high hardness, organic load indicators, and episodic microbiological contamination in several samples. A low-cost four-stage household treatment procedure combining chemical oxidation, thermal treatment, sorption, and short-term preservation was evaluated as a preliminary emergency approach. The procedure improved odor, taste, hardness, iron content, permanganate oxidizability, and microbiological safety; however, it did not fully reduce total dissolved solids, sulfates, or chlorides to drinking-water standards. Therefore, the treated water should be considered non-potable and suitable mainly for limited domestic and hygienic uses unless additional desalination or blending is applied. The study highlights both the potential and the limitations of simple household-level interventions under emergency water supply disruption and emphasizes the need for decentralized treatment support, monitoring, and long-term infrastructure recovery. Full article

Bismuth-based semiconductors have emerged as a promising class of visible-light-responsive photo(electro)catalysts for environmental remediation owing to their tunable electronic structures, moderate band gaps, and relatively low toxicity. The stereochemically active Bi³⁺ 6s² lone pair and strong Bi–O orbital hybridization tailor valence-band states, enabling enhanced utilization of the solar spectrum and favorable charge-carrier dynamics. In addition, layered, perovskite-like, and aurivillius-type crystal frameworks generate internal electric fields that are advantageous for photoelectrochemical (PEC) operation. This review critically examines advances from 2015 to 2025 in the design, synthesis, modification, and environmental applications of bismuth-based photo(electro)catalysts, with particular emphasis on PEC systems for pollutant degradation. Major material families, including bismuth oxides, oxyhalides, oxychalcogenides, chalcogenides, perovskite-like oxides, and complex metal oxides, are discussed in relation to their structure–property–performance relationships. Key synthesis strategies, such as solid-state, sol–gel, hydro/solvothermal, microwave-assisted, spray pyrolysis, and electrodeposition methods, are compared with respect to morphology control, defect chemistry, and electrode integration. Performance-enhancing approaches, including elemental doping, oxygen-vacancy engineering, and the rational design of type-II, p–n, Z-scheme, and S-scheme heterojunctions, are critically assessed. Practical considerations related to stability, scalability, and techno-economic constraints are highlighted. Finally, current challenges and future directions toward durable and application-ready bismuth-based PEC technologies are outlined. Full article

Protein phosphorylation and dephosphorylation reactions of intracellular molecules catalyzed by enzymes such as kinases and phosphatases are essential reactions in a lot of cellular functions such as intracellular signal transduction in living systems. The design and synthesis of artificial enzyme mimics are important research topics in bioorganic and bioinorganic chemistry. In this paper, we report on the construction of artificial phosphatases via the supramolecular self-assembly of compounds such as an amphiphilic bis(Zn²⁺-cyclen) (cyclen = 1,4,7,10-tetraazacyclododecane) complex, barbital derivatives modified with benzocrown ethers and boronophenyl groups, and a copper(II) ion in a two-phase solvent system. We have developed a hypothesis whereby a mono(4-nitrophenyl)phosphate (MNP) substrate coordinates to the Cu₂(µ-OH)₂ core in supramolecular complexes and is activated either by Lewis acidic units such as alkali metal (Li⁺, Na⁺ and K⁺)-benzocrown ether complexes or by boronophenyl moieties. The findings suggest that supramolecular phosphatase functionalized with a benzo-12-crown-4-Li⁺ complex shows a higher level of activity in the MNP hydrolysis of a two-phase solvent system compared with that of our previous supramolecular phosphatases in terms of hydrolysis activity and catalytic turnover. Full article

Copper and zinc nanoparticles have been suggested as potent anticancer agents, particularly against osteosarcoma, a highly aggressive bone cancer with limited treatment options. In order to avoid systemic toxicity, biomolecular carriers able to chelate metal ions and deliver them in a targeted manner to the vicinity of cancer cells need to be developed. Herein, we have used a histidine-containing, cyclic dipeptide as a carrier able to chelate stabilized copper and zinc nanoparticles. The cyclic peptide cyclo-(histidine-phenylalanine) (cHF) self-assembled into amyloid-type fibrils; morphological and structural characterization following metal addition confirmed the formation of cHF−CuNPs and cHF–ZnNPs. These composite nanoparticles demonstrated bacteriostatic activity against Escherichia coli and Staphylococcus aureus at the in vitro level. We evaluated the optimal concentration of cHF–metalNP complexes with limited cytotoxicity to L929 fibroblasts and high cytotoxic effects against MG-63 osteosarcoma cells. Their cytotoxicity was particularly pronounced at pH 6.4, which emulates the tumor microenvironment. The cHF peptide alone did not demonstrate significant antimicrobial or cytotoxic effects to both cell types, suggesting that it can act as a cytocompatible, pH-responsive carrier of metal ions with targeted dual functionality against both microbial infections and osteosarcoma cancer cells. Full article

Lanthanide ions and their complexes have emerged as versatile tools in biology and medicine owing to their unique photophysical, magnetic, and coordination properties. Their applications span bioimaging, sensing, therapy and diagnostics, underpinned by their strong preference for oxygen-donor ligands, kinetic stability, and tunable luminescence. This review integrates current developments in lanthanide coordination chemistry, focusing on the mechanistic basis of their interactions with biomolecules such as nucleic acids, proteins, and peptides. Moreover, this work highlights the design principles governing complex stability and biological compatibility, summarizing key biomedical uses of lanthanides ranging from imaging and drug delivery to anticancer and antioxidant effects, and discusses their toxicity and biodistribution, and their potential for clinical translation. In particular, this review offers a mechanistically oriented synthesis of recent advances, emphasizing the interplay between coordination behavior and biological function, and identifying emerging trends that define the current landscape of lanthanide-based bioinorganic research. By correlating molecular coordination features with biological performance, the review identifies the main trends shaping lanthanide-based bioinorganic research, also including a brief discussion of complexes formed between lanthanides and naturally occurring molecules, such as amino acids. Full article

Organometallic and metal–organic compounds are widely used in different fields of chemistry and allied disciplines, including bioinorganic and medicinal chemistry. Of particular interest is the development of novel potential anticancer agents based on palladium(II) complexes of the so-called pincer-type ligands, featuring a specific monoanionic tridentate framework. In this work, hybrid imine–thiocarbamate ligands are shown to readily undergo direct cyclopalladation in solution and under solvent-free conditions, in particular upon mechanochemical activation, yielding a series of Pd(II) pincer complexes. The latter exhibit promising cytotoxic activity against several solid and hematopoietic cancer cell lines. Full article

This study explores the multifaceted anticancer mechanisms of flavanone analogues and spiropyrazoline condensed with flavanone ring against colorectal cancer (CRC) cell lines. Five-membered heteroaromatic scaffolds, in particular, have gained prominence in medicinal chemistry as they offer enhanced metabolic stability, solubility and bioavailability, crucial factors in developing effective drugs. Building upon previous findings, we investigated three lead derivatives (1, 3, and 5) with potent antiproliferative activity (IC₅₀ < 35 μM). The compounds induced pronounced oxidative stress, evidenced by increased lipid peroxidation and reduced membrane fluidity, primarily within the hydrophobic layers of cell membranes. Preincubation with the antioxidant N-acetylcysteine (NAC) significantly attenuated these effects, confirming the pivotal role of reactive oxygen species (ROS) in their cytotoxicity. Mechanistic studies revealed that the derivatives triggered intrinsic apoptosis, characterized by the cleavage of PARP and the activation of caspase-9 and caspase-3. Furthermore, the compounds modulated key signaling pathways involved in cell survival and proliferation. Specifically, they inhibited the pro-oncogenic ERK1/2 MAPK pathway while inducing cell line-dependent alterations in p38 and JNK activity. Concurrently, all derivatives reduced the level of the transcription factor Nrf2, a master regulator of antioxidant defense and a mediator of chemoresistance in CRC. Collectively, these findings indicate that flavanone/chromanone derivatives exert their anticancer activity through a synergistic mechanism involving ROS generation, disruption of redox homeostasis, inhibition of Nrf2 signaling, and modulation of MAPK-dependent apoptotic pathways. These results highlight the therapeutic potential of flavanone-based compounds and their spiropyrazoline analogues as multifunctional anticancer agents targeting oxidative stress and survival signaling in colorectal cancer. Full article

Cancer ranks as a major cause of morbidity and mortality across the globe, notably in economically developed regions, and its incidence is predicted to rise in the coming decades. Metal-based compounds represent a particularly promising class of pharmaceuticals for the treatment of cancer. Following the success of platinum in cancer therapy, attention soon turned to other transition metals, particularly the platinum group metals such as ruthenium and palladium. Despite the high anticancer efficacy of many of its compounds, osmium remained one of the least investigated of these metals for a long time, partly due to concerns about its toxicity. However, there has been a recent resurgence in the preparation and evaluation of osmium complexes, which exhibit high structural variability and demonstrate promising anticancer activity. The present review aims to survey recent developments in this exciting field, focusing on osmium complexes of the non-arene type reported during the last decade. Full article

Background/Objectives: First row transition metal ions have recently regained attention in coordination chemistry as alternatives to gadolinium-based paramagnetic contrast agents, motivated by emerging safety concerns associated with certain Gd³⁺-based contrast agents. In this study, we report the development of a novel homoleptic diketonate Fe³⁺ complex functionalized with biocompatible indole moieties. We investigate its potential as a paramagnetic relaxation agent by evaluating its ability to modulate the T₁ and T₂ relaxation times of water proton. Methods: Iron(III) tris-1,3-(1-methylindol-3-yl)propanedionate [Fe(BIP)₃] was synthesized via a thermal method from bis(1-methylindol-3-yl)-1,3-propanedione (HBIP) using Fe(ClO₄)₃∙6 H₂O as the metal source. The complex was characterized by UV-Vis, IR and NMR spectroscopy, differential scanning calorimetry–thermogravimetric analysis, and single-crystal X-ray diffraction. Fe(BIP)₃ aggregation behavior in aqueous environment, including size and morphology of aggregates, was investigated using dynamic light scattering and scanning electron microscopy. Incorporation of the aggregates into phospholipid vesicles was evaluated by fluorescence resonance energy transfer and fluorescence correlation spectroscopy. The paramagnetic properties of monomeric Fe(BIP)₃ were probed in solution by nuclear magnetic resonance recurring to the Evans bulk magnetization method. Results: The designed synthetic procedure successfully afforded Fe(BIP)₃, which was fully characterized by UV-Vis and IR spectroscopy, as well as single-crystal X-ray diffraction. Aqueous solutions of Fe(BIP)₃ spontaneously formed rice-grain-shaped nanoscale aggregates of hydrodynamic radius ≈ 30 nm. Incorporation of these aggregates into phospholipid vesicles enhanced their stability. The longitudinal r₁ and transverse r₂ relaxivities of Fe(BIP)₃ aggregates were assessed to be 1.92 and 52.3 mM⁻¹s⁻¹, respectively, revealing their potential as paramagnetic relaxation agents. Conclusions: Fe(BIP)₃ aggregates, stabilized through incorporation into phospholipid vesicles, demonstrate promising potential as novel paramagnetic relaxation agents in aqueous environments. Full article

A novel heterobimetallic ruthenium(II)–gold(I) complex featuring a bridging bis(diphenylphosphino)butane (dppb) ligand was prepared and fully characterized. Single-crystal X-ray diffraction revealed a piano-stool geometry around Ru(II) with η⁶-cymene, two chlorido ligands, and one phosphorus atom from dppb, while the Au(I) center adopts a linear P–Au–Cl coordination. Structural integrity in the solution was confirmed by 1D and 2D NMR spectroscopy, while solution behavior was further monitored by variable solvent ³¹P NMR and UV/Vis spectroscopy, indicating that the organometallic Ru–arene core remains intact, whereas the chlorido ligands coordinated to Ru exhibit partial lability. Complementary characterization included elemental analysis, FTIR, and UV/Vis spectroscopy. Spectrofluorimetric and FRET analyses showed that Au(dppb), Ru(dppb), and the heterobimetallic AuRu complex bind to BSA with apparent constants of 1.41 × 10⁵, 5.12 × 10², and 2.66 × 10⁴ M⁻¹, respectively, following a static quenching mechanism. In vivo biological evaluation in Wistar rats revealed no significant hepatotoxicity or nephrotoxicity, with only mild and reversible histological alterations and preserved hepatocyte nuclear morphology. Hematological analysis indicated a statistically significant reduction in leukocyte populations, suggesting immunomodulatory potential, while elevated serum glucose levels point to possible endocrine or metabolic activity. These findings highlight compound structural stability and intriguing bioactivity profile, making it a promising platform for further organometallic drug development and testing. Full article

This study developed a beta-cyclodextrin polymer crosslinked with citric acid (CDCAPol) for removing water contaminants using methylene blue (MB) as a model compound. The polymer, which features free carboxyl groups and cyclodextrin cavities, demonstrated high adsorptive capacity. Under optimal conditions (0.01 g adsorbent, pH 6, and 50 mg/dm³ MB), a removal efficiency of 99.2% was achieved, with a maximum adsorption capacity of 126.58 mg/g as determined by the Langmuir isotherm. Kinetic data fit the best to the pseudo-second-order model, highlighting strong interactions between MB and the polymer. This promising material may find applications in wastewater treatment and environmental protection. Full article

Humans are being exposed to a variety of potentially toxic metal compounds through the diet and/or the intravenous administration of metal-containing medicinal drugs. The organomercurial thimerosal (THI) is a bactericidal that is present in vaccines, but its potential degradation by biomolecules in vivo is incompletely understood. To probe its interaction with low-molecular-weight thiols that are highly abundant within cells, we have employed an LC-based analytical approach in conjunction with a mercury-specific detector. The injection of THI into a C₁₈-HPLC column equilibrated with mobile phases that contained increasing concentrations of up to 15 mM of glutathione (GSH) and 30% acetonitrile revealed the elution of a GS-EtHg adduct in conjunction with THI, as evidenced by electrospray ionization mass spectrometry. These results were confirmed by ¹⁹⁹Hg-NMR spectroscopy. While these results imply a rapid degradation of THI by GSH at physiological pH, it is important to point out that our results were obtained in aqueous solutions containing 30% (v:v) acetonitrile. Further studies need to confirm if the GS-EtHg adduct is also formed in biological fluids. Our results nevertheless demonstrate that GSH and L-cysteine (Cys) are potential targets of THI at physiological pH, which is relevant to better understand its side effects, including previously reported effects on Ca²⁺ channels. Full article

Bryostatin 1, a natural macrolide isolated from Bugula neritina, is a potent modulator of protein kinase C (PKC) isoforms with promising anticancer properties. In numerous in vitro studies, bryostatin 1 has been shown to inhibit tumor cell proliferation and induce differentiation and apoptotic cell death in a wide range of cell lines, including leukemia, lymphoma, glioma, and solid tumors such as ovarian and breast cancer. Its antitumor activity, both as monotherapy and in combination with conventional chemotherapy, has been confirmed in in vivo models, where synergistic effects have been observed, including sensitization of tumor cells to cytostatic agents. Despite promising preclinical findings, phase I and II clinical trials have not yielded the expected results, suggesting limited efficacy of the macrolide as a single agent with a relatively favorable safety profile. Current research directions focus on optimizing dosing regimens, combining bryostatin 1 with other anticancer drugs and identifying predictive biomarkers of response. This article reviews the current state of knowledge on the anticancer effects of bryostatin 1, analyzing available data from in vitro, in vivo, and clinical trials and discussing potential directions for further translational research. Full article

The gastrointestinal tract mediates the absorption of nutrients from the diet, which is increasingly contaminated with toxic metal(loid) species (TMs) and thus threatens food safety. Evidence in support of the influx of TMs into the bloodstream of the general and vulnerable populations (babies, children, pregnant women, and industrial workers) has been obtained by accurately quantifying their blood concentrations. The interpretation of these TM blood concentrations, however, is problematic, as we cannot distinguish between those that are tolerable from those that may cause the onset of environmental diseases. Since TMs that have invaded the bloodstream may perturb biochemical processes therein that will eventually cause organ damage it is crucial to better understand their bioinorganic chemistry as these processes collectively determine their organ availability. Thus, bioinorganic processes of TMs in the bloodstream represent selectivity filters which protect organs from their influx and ultimately determine the corresponding exposure-response relationships. The need to better understand selectivity filters prompted us to mechanistically disentangle them into the major bioinorganic chemistry processes. It is argued that the detoxification of TMs in the bloodstream and the biomolecular mechanisms, which mediate their uptake into target organs, represent critical knowledge gaps to revise regulatory frameworks to reduce the disease burden. Full article