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Removing heavy metal (loid) s (HMs) from contaminated soil in a nonselective, highly efficient, and energy‐free manner is a major global challenge. Herein, this work synthesizes and assembles a biomimetic materials system (BMS) consisting of an artificial plant, a hemispherical glass cover, and a reflective plate, capable of non‐selective and highly efficient remediation of soil contaminated by various HM ions under sunlight. Specifically, a water cycle is driven to establish between the soil, artificial plant, and atmosphere by solar energy in the BMS, which induced water‐soluble HM ions to enrich and precipitate at the top edge of the artificial plant. The formed HM precipitate is easily removed, contributing to the extremely strong recyclability of BMS. This system has significant advantages in terms of soil properties, contamination characteristics, energy consumption, processing time, and removal amount over other representative remediation methods, demonstrating its great potential for practical application in the remediation of various HM‐contaminated soils. [ABSTRACT FROM AUTHOR]

Although catenated cages have been widely constructed due to their unique and elegant topological structures, cyclic catenanes formed by the connection of multiple catenane units have been rarely reported. Herein, based on the orthogonal metal‐coordination‐driven self‐assembly, we prepare a series of heterometallic [2]catenanes and cyclic bis[2]catenanes, whose structures are clearly evidenced by single‐crystal X‐ray analysis. Owing to the multiple positively charged nature, as well as the potential synergistic effect of the Cu(I) and Pt(II) metal ions, the cyclic bis[2]catenanes display broad‐spectrum antibacterial activity. This work not only provides an efficient strategy for the construction of heterometallic [2]catenanes and cyclic bis[2]catenanes but also explores their applications as superior antibacterial agents, which will promote the construction of advanced supramolecular structures for biomedical applications. [ABSTRACT FROM AUTHOR]

Self-assembling short peptide amphiphiles, crafted through a minimalistic approach, spontaneously generate well-ordered nanostructures, facilitating the creation of precise nanostructured biomaterials for diverse biomedical applications. The seamless integration of bioactive metal ions and nanoparticles endows them with the potential to serve as pioneering materials in combating bacterial infections. Nanomanipulation of these molecules' binary structures enables effective penetration of membranes, forming structured nanoarchitectures with antibacterial properties. Through a comprehensive exploration, we attempt to reveal the innovative potential of short peptide amphiphiles, particularly in conjugation with metal cations and nanoparticles, offering insights for future research trajectories. [ABSTRACT FROM AUTHOR]

Glucoraphanin (GRA) produced by the hairy roots of broccoli (Brassica oleracea L. variety Italica Planch) is converted to the secondary metabolite Sulforaphane (SF), which has anticancer properties under specific conditions, and the synthesis of SF is significantly affected by both Ca2+ and Fe2+. Based on the screening of GRA, SF yields, and Epithiospecififier Protein (ESP) activity, the optimal concentration of exogenously added metal ion chelator Ethylene Glycol bis (2-aminoethyl) Tetraacetic Acid (EGTA) for the treatment of broccoli hairy roots and the optimal treatment time were 8.0 mM EGTA for 48 h. Fe2+ content in hairy roots of broccoli reached the lowest level at 48 h, and also significantly reduce the Ca2+ content, but the Ca2+ content recovered with the treatment time and reached the highest level at 48 h. Analysis of transcriptomics data indicated that the physiological and biochemical responses of broccoli hairy roots to exogenous additions of EGTA to metabolic pathways were mainly mediated by the regulation of the expression of relevant genes involved in signal transduction and amino acid metabolism. The expression of NSP2, NSP5, and ESP decreased with the increase of EGTA treatment time and was lowest at 48 h. The expression of 12 genes, such as AOP1.2.7, GSTF11 increased with the increase of EGTA treatment time, and the highest expression was found at 48 h. This study presented a theoretical basis for the study of the exogenous addition of EGTA to alter Ca2+ and Fe2+ contents and affect SF synthesis. [ABSTRACT FROM AUTHOR]

2,4-dimethyl-6-(1-phenyl-1H-benzimidazol-2-yl)phenol (DPBP) has been prepared and characterized by 1H NMR, 13C NMR, mass spectral studies and elemental analysis. DPBP shows On/off fluorescence system (fluorescence enhancing and quenching) by tuning with Fe3+ metal ion and H3PO4. Addition of Fe3+ ions into DPBP results in quenching of fluorescence. Other cations, including Zn2+, Ni2+, Pb2+, Ca2+, Co2+, Cd2+ and Mg2+ had little effect in the fluorescence intensity. The addition of H3PO4 with Fe3+-DPBP complex results in the enhanced fluorescence due to the detachment of Fe3+-DPBP complex. Dual emission has been observed by DPBP in non-polar solvent medium whereas single emission was observed in polar solvents due to Intra and Intermolecular hydrogen bonding respectively. Shorter wavelength emission of DPBP is due to enol rotamer and longer wavelength emission of DPBP is due to keto rotamer. [ABSTRACT FROM AUTHOR]

Film heterostructures of compositions Ag/Au/Ti and Ag/Au/CFR-PEEK are obtained by thermal evaporation with subsequent deposition of metallic gold sublayers and silver nanostructures on modern biomaterials (Ti-6Al-4V alloy, polyether ether ketone CFR-PEEK). Silver concentration is varied within 2.1-20.8 µg/cm2 by changing the initial metal portion (1.2-5 mg) and the number of successive depositions (1–3). According to SEM data, Ag nanofilms with a thickness up to 10-15 nm are formed on the surface of gold sublayers. According to XPS results, gold is present in the metallic state on the surface of biomaterials whereas along with metal, the Ag2O oxide phase is detected for silver. The dynamics of silver dissolution from the Ag/Au surface is analyzed by ICP-AES (2-48 h). It is found that regardless of the silver concentration, the samples demonstrate moderate dynamics of releasing metal ions; some amount of gold is detected together with silver in the solution. The absence of cytotoxicity of the synthesized film heterostructures in vitro (L-929 cells, viability >95-98%) is shown. Heterostructures completely suppress the growth of colonies of Gram-negative (P. aeruginosa) and Gram-positive (S. aureus) bacteria after 6 h and 24 h action respectively. [ABSTRACT FROM AUTHOR]

A new quinoline‐based COF (covalent organic framework), obtained by Povarov reaction, containing 2,6‐diisopropylphenyl moieties as substituents over the heterocyclic ring is described for detecting Zn2+ in aqueous solution. The introduction of the mentioned bulky phenyl rings into the network favors an increase of the distance between the reticular sheets and their arrangement, obtaining a new material with an alternating AB type stacking. The new material exhibits good selectivity to detect Zn2+ by fluorescence emission in aqueous solutions up to a concentration of 1.2 × 10−4 m of the metal ion. In order to have a deeper insight into the interaction between the COF and the zinc cation, a thorough spectroscopical, microscopical, and theoretical study is also presented and discussed in this communication. [ABSTRACT FROM AUTHOR]

Screen-printed electrodes (SPEs) are reliable, portable, affordable, and versatile electrochemical platforms for the real-time analytical monitoring of emerging analytes in the environmental, clinical, and agricultural fields. The aim of this study was to evaluate the electrochemical behavior of gold screen-printed electrodes (SPGEs) modified with molecules containing amino (Tr-N) or α-aminophosphonate (Tr-P) groups for the selective and sensitive detection of the toxic metal ions Pb2+ and Hg2+ in aqueous samples. After optimizing the analytical parameters (conditioning potential and time, deposition potential and time, pH and concentration of the supporting electrolyte), anodic square wave stripping voltammetry (SWASV) was used to evaluate and compare the electrochemical performance of bare or modified electrodes for the detection of Hg2+ and Pb2+, either alone or in their mixtures in the concentration range between 1 nM and 10 nM. A significative improvement in the detection ability of Pb2+ ions was recorded for the amino-functionalized gold sensor SPGE-N, while the presence of a phosphonate moiety in SPGE-P led to greater sensitivity towards Hg2+ ions. The developed sensors allow the detection of Pb2+ and Hg2+ with a limit of detection (LOD) of 0.41 nM and 35 pM, respectively, below the legal limits for these heavy metal ions in drinking water or food, while the sensitivity was 5.84 µA nM−1cm−2 and 10 µA nM−1cm−2, respectively, for Pb2+ and Hg2+. The reported results are promising for the development of advanced devices for the in situ and cost-effective monitoring of heavy metals, even in trace amounts, in water resources. [ABSTRACT FROM AUTHOR]

Background: This longitudinal prospective study aimed to assess orthodontic patients' immune system response to metal ion release in saliva. Methods: Thirty adult patients (18–35 years) were equally divided into three groups: groups at the end (G1) and beginning (G2) of multibracket appliances (MBA) treatment and a non-treated control group (G3). Participants were evaluated at four timepoints within 21 days, with saliva samples being analyzed for metal ion concentrations and blood for the lymphocyte transformation test (LTT). Results: There were no significant differences between groups or timepoints for saliva. LTT analyses revealed hypersensitivity in one-third of all patients and 50% of G2 for nickel, with three developing sensitizations after MBA insertion. All nickel-sensitized patients exhibited varying elevated saliva nickel concentrations. The most nickel-sensitized patients had low ion saliva loads. In borderline nickel-sensitization cases, saliva ion concentrations were up to 20 times higher than the reference. Hypersensitivity to palladium, gold, and mercury was also observed. Conclusions: These findings indicate that increased MBA ion release was not inherently linked to the immune response (Type-IV sensitization), as reactions occurred even with ion levels below thresholds. This underlines the need for a comprehensive evaluation of the immune response to metal ion release in orthodontic patients. [ABSTRACT FROM AUTHOR]

In this study, amorphous zirconium phosphate were synthesized (Am-ZrP) through a facile method and then composited with cotton fiber (Am-Co) for the utilization of heavy metal ions adsorptive elimination. In the research, Am-Co exhibited a higher adsorption capacities compared with Am-ZrP, with 85.69 mg/g for Cu2+, 30.73 mg/g for Ni2+, 56.74 mg/g for Cd2+. The adsorption kinetics of the adsorbents was extrapolated using pseudo-first-order and pseudo-second-order kinetic model and the experimental data were found to fit pseudo-second-order more than pseudo-first-order. Langmuir and Freundlich isotherm model were also applied in the study to reflect the interaction between adsorbate and adsorbent. In this research, the adsorption isotherm of Am-ZrP and Am-Co fitted the Langmuir model favorably. The results indicated that the Am-Co was a promising candidate for practical application in the treatment of wastewater contaminated by heavy metal ions. [ABSTRACT FROM AUTHOR]

Porous carbon materials have attracted considerable interest and show great potential for various applications because of their remarkable properties, including high specific surface area, unique porous structures, mass transport, easily accessible active sites, controllable surface chemistry, etc. Owing to these properties, porous carbons can be employed in environmental remediation as adsorbents for eliminating pollutants such as carbon dioxide (CO2) from the atmosphere and oil and heavy metal ions from aquatic ecosystems. In this minireview, we grouped porous carbons into three main parts based on their dimensions, and the recent progress in porous carbon application as adsorbents for environmental remediation, including oil-water separation, CO2 capture, and heavy metal ion removal, are discussed according to their dimensions. [ABSTRACT FROM AUTHOR]

The use of non ferrous smelting slag to prepare new types of cementitious materials is an important way to realize the resource utilization of solid waste. The gelation mechanism and mechanical properties are the focus of research on non ferrous smelting slag based cementitious materials, and the leaning and solidification mechanisms of heavy metal ions have been receiving increasing attention nowadays. In this article, the morphology and structure of non ferrous smelting slag are described, the existence form and immobilization principle of heavy metal ions in non ferrous smelting slag based cementitious materials are summarized systematically. This review can provide reference for the study of heavy metal immobilization in the application of smelting slag based cementitious materials. [ABSTRACT FROM AUTHOR]

Cancer is the second leading cause of death in the world following cardiovascular disease. Its treatment, including radiation therapy and surgical removal of the tumour, is based on pharmacotherapy, which prompts a constant search for new and more effective drugs. There are high costs associated with designing, synthesising, and marketing new substances. Drug repositioning is an attractive solution. Fluoroquinolones make up a group of synthetic antibiotics with a broad spectrum of activity in bacterial diseases. Moreover, those compounds are of particular interest to researchers as a result of reports of their antiproliferative effects on the cells of the most lethal cancers. This article presents the current progress in the development of new fluoroquinolone derivatives with potential anticancer and cytotoxic activity, as well as structure–activity relationships, along with possible directions for further development. [ABSTRACT FROM AUTHOR]

Nanoparticles are structures that possess unique properties with high surface area-to-volume ratio. Their small size, up to 100 nm, and potential for surface modifications have enabled their use in a wide range of applications. Various factors influence the properties and applications of NPs, including the synthesis method and physical attributes such as size and shape. Additionally, the materials used in the synthesis of NPs are primary determinants of their application. Based on the chosen material, NPs are generally classified into three categories: organic, inorganic, and carbon-based. These categories include a variety of materials, such as proteins, polymers, metal ions, lipids and derivatives, magnetic minerals, and so on. Each material possesses unique attributes that influence the activity and application of the NPs. Consequently, certain NPs are typically used in particular areas because they possess higher efficiency along with tenable toxicity. Therefore, the classification and the base material in the NP synthesis hold significant importance in both NP research and application. In this paper, we discuss these classifications, exemplify most of the major materials, and categorize them according to their preferred area of application. This review provides an overall review of the materials, including their application, and toxicity. [ABSTRACT FROM AUTHOR]

The genus Pristimantis diversified in the tropical Andes mountains and is the most speciose genus of terrestrial vertebrates. Pristimantis are notable among frogs in that they thrive at high elevations (>2,000 m) and are direct developers without a tadpole stage. Despite their ecological significance, little is known about the genetic and physiological traits enabling their success. We conducted transcriptomic analysis on seven Pristimantis species sampled across elevations in the Ecuadorean Andes to explore three hypotheses for their success: (i) unique genes are under selection relative to all other frogs, (ii) common selection occurs across all direct developers, or (iii) common selection occurs across all high-elevation frog clades. Comparative analysis with 34 frog species revealed unique positive selection in Pristimantis genes related to aerobic respiration, hemostasis, signaling, cellular transportation of proteins and ions, and immunity. Additionally, we detected positive selection across all direct developers for genes associated with oxygenase activity and metal ion binding. While many genes under selection in Pristimantis were not positively selected in other high-elevation frog species, we identified some shared genes and pathways linked to lipid metabolism, innate immunity, and cellular redox processes. We observed more positive selection in duplicated- versus single-copy genes, while relaxed purifying selection was prevalent in single-copy genes. Notably, copy number of an innate immunity complement gene was positively correlated with Pristimantis species elevation. Our findings contribute novel insights into the genetic basis of adaptation in Pristimantis and provide a foundation for future studies on the evolutionary mechanisms leading to direct development and coping with high elevations. [ABSTRACT FROM AUTHOR]

Crosslinked polyamidoximes (PAOs) were synthesized using terephthaloyl chloride (TPC) as a crosslinking agent, which interacted with the pendant amidoxime groups on the polymer chains. The incorporation of a stiff 1,2,4-oxadiazole bridging unit was achieved by reacting TPC with PAOs in tetrahydrofuran (THF) under reflux. The linkage was verified using FTIR spectroscopy to identify the characteristic functional groups in the crosslinked polyamidoximes. X-ray diffraction (XRD) patterns indicated improved chain alignment due to crosslinking. Additionally, the thermal stability of crosslinked PAOs increased significantly to a range of 515–593 °C, compared to 426–489 °C for non-crosslinked PAOs. These crosslinked PAOs were tested for their effectiveness in removing metal ions through a batch process. Optimal conditions resulted in maximum adsorption efficiencies of 86% for Cd (II) and 88% for Pb (II) at pH 6, with a contact time of 3 h, a feed concentration of 40 mg/L, and 0.1 g of adsorbent. The adsorption mechanism conformed more closely to the Langmuir isotherm than the Freundlich model. In competitive adsorption, the order of metal uptake was Fe (II) > Pb (II) > Cd (II) > Cu (II). Consequently, this class of crosslinked polyamidoximes shows potential for use in water treatment applications for removing heavy metal ions. [ABSTRACT FROM AUTHOR]

Pb(II) can accumulate in the body and gradually cause irreversible harm. In this work, a dual-mode colorimetric biosensor based on an aptamer was developed as an effective method for sensitive sensing of Pb(II). The aptamers were immobilized on silver nanoparticles (Ag NPs) by Ag–S bonding to increase the active sites on the electrode surface. Gold–palladium bimetallic nanoparticles (Au@Pd NPs) can not only serve as signal indicators but also play a role as nanozymes. On the one hand, Au@Pd NPs were modified on the aptamer to improve the conductivity of the sensor for the detection of Pb(II) by the electrochemical method of differential pulse voltammetry (DPV). On the other hand, Au@Pd NPs were porous nanomaterials with numerous active sites on their surface that can catalyze the decomposition of hydrogen peroxide (H2O2) in solution to generate O2, so that 3,3′,5,5′-tetramethylbenzidine (TMB) was oxidized to blue oxTMB, enabling the visual prediction of Pb(II). At the same time, with the property that 8–17 deoxyribozyme and metal ions can co-catalyze, it promoted the binding of Au@Pd NPs functionalized aptamer to the electrode in the presence of Pb(II) and enhanced the electrochemical signal. Under optimal conditions, the detection range of Pb(II) was 1—1000 nmol L−1, and the limit of detection (LOD) was 0.4 nmol L−1. The biosensor has been successfully applied to the detection of edible mushroom samples. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor based on multiwalled carbon nanotubes (MWCNTs) and 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) hydrophobic ionic liquid for the rapid detection of Pb2+ and Cd2+ was developed. In this study, the BMIMPF6-MWCNTs composite, as well as BMIMPF6 and MWCNTs, were characterized using SEM. The electrochemical studies were performed using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The BMIMPF6-MWCNTs/GCE exhibited excellent electrochemical activity. The effect of the pH value of 0.1 M NaAc/HAc buffer, deposition potential, and deposition time was investigated. Under the optimal conditions, the linear range for the modified sensors varies from 5 to 1850 µg L−1 for Pb2+ and 22 to 600 µg L−1 for Cd2+. The limit of detection (LOD) for Pb2+ and Cd2+ was 0.9 µg L−1 and 0.5 µg L−1, respectively, and the limit of quantification (LOQ) was 3 µg L−1 for Pb2+ and 1.7 µg L−1 for Cd2+. Moreover, this method showed excellent anti-interference performance, short analysis time, and practicability for determining Pb2+ and Cd2+. The electrochemical sensor was able to determine heavy metal ions in actual water samples without complex pretreatment, with acceptable recoveries from 98 to 110.8% for Pb2+ and 98.6 to 111.3% for Cd2+, demonstrating that the sensor based on BMIMPF6-MWCNTs/GCE can apply for Pb2+ and Cd2+ quantification. [ABSTRACT FROM AUTHOR]

Triphenylamine (TPA)‐based Schiff base chemosensors ((E)‐2‐((4‐(diphenylamino)benzylidene)amino)phenol [TPA‐AP], (E)‐5‐(diphenylamino)‐2‐(((2‐hydroxyphenyl)imino)methyl)phenol [HTPA‐AP], and (E)‐5‐(diphenylamino)‐2‐((phenylimino)methyl)phenol [HTPA‐A]) were synthesized and explored the role of metal chelating hydroxyl functionality position for heavy metal ion sensing. TPA‐AP and HTPA‐AP showed Cu2+ ion‐induced chemical transformation and produced oxazole derivatives with turn‐on fluorescence. In contrast, HTPA‐A exhibited metal chelation‐induced turn‐on fluorescence for Zn2+ ion. The reactive chemical sensing of TPA‐AP and HTPA‐AP led to high selectivity of Cu2+, and other ions did not show any interference. The concentration‐dependent studies of Cu2+ and Zn2+ indicated the limit of detection (LOD) up to 6.07 × 10−7 and 4.6 × 10−7 M, respectively. Further, Cr3+, Fe3+, and Fe2+ coordination with TPA‐AP and HTPA‐AP exhibited visible color change from colorless to yellow. However, the yellow color was disappeared and becomes colorless due to imine hydrolysis. Interestingly, all three metal ions showed different rate of hydrolysis and color disappearance. TPA‐AP with Fe3+ exhibited fast hydrolysis and immediate color change whereas Fe2+ and Cr3+ required longer time. But HTPA‐AP and HTPA‐A produced stable complexes with Cr3+, Fe2+, and Sn2+ and Fe3+ alone showed hydrolysis. Thus, the present studies provide structural insight for designing reactive fluorescence and colorimetric Schiff base chemosensor for heavy metal ions. [ABSTRACT FROM AUTHOR]

Glutaminyl-peptide cyclotransferases (QCs) convert the N-terminal glutamine or glutamate residues of protein and peptide substrates into pyroglutamate (pE) by releasing ammonia or a water molecule. The N-terminal pE modification protects peptides/proteins against proteolytic degradation by amino- or exopeptidases, increasing their stability. Mammalian QC is abundant in the brain and a large amount of evidence indicates that pE peptides are involved in the onset of neural human pathologies such as Alzheimer's and Huntington's disease and synucleinopathies. Hence, human QC (hQC) has become an intensively studied target for drug development against these diseases. Soon after its characterization, hQC was identified as a Zn-dependent enzyme, but a partial restoration of the enzyme activity in the presence of the Co(II) ion was also reported, suggesting a possible role of this metal ion in catalysis. The present work aims to investigate the structure of demetallated hQC and of the reconstituted enzyme with Zn(II) and Co(II) and their behavior in the presence of known inhibitors. Furthermore, our structural determinations provide a possible explanation for the presence of the mononuclear metal binding site of hQC, despite the presence of the same conserved metal binding motifs present in distantly related dinuclear aminopeptidase enzymes. [ABSTRACT FROM AUTHOR]

Controlling the optical activity of halide perovskite materials through modulation of the coordination configurations of the metal ions is important. Herein, a novel manganese‐based halide, specifically diaquatetrakis(methyldiphenylphosphine oxide)manganese(II) tetrachloridomanganate(II), [Mn(C13H13OP)4(H2O)2][MnCl4] or [Mn(MDPPO)4(H2O)2][MnCl4] (MDPPO is methyldiphenylphosphine oxide), was synthesized through the solvothermal reaction of MnCl2 with the neutral molecule MDPPO. In this compound, [Mn(MDPPO)4(H2O)2]2+ acts as the cation, while [MnCl4]2− serves as the anion, enabling the co‐existence of tetrahedral and octahedral structures within the same system. Remarkably, the compound exhibits efficient red‐light emission at 662 nm, distinct from the green‐light emission typically observed in MnX4‐based halides. Theoretical calculations show that the red emission comes from the charge transfer from the MDPPO to the Mn2+ of [MnCl4]2−. This work provides a new perspective for the design and synthesis of red‐light‐emitting manganese‐based halides with unique structures. [ABSTRACT FROM AUTHOR]

The development of portable and efficient nanoprobes to realize the quantitative/qualitative onsite determination of food pollutants is of immense importance for safeguarding human health and food safety. With the advent of the smartphone, the digital imaging property causes it to be an ideal diagnostic substrate to point-of-care analysis probes. Besides, merging the versatility of carbon dots nanostructures and bioreceptor abilities has opened an innovative assortment of construction blocks to design advanced nanoprobes or improving those existing ones. On this ground, massive endeavors have been made to combine mobile phones with smart nanomaterials to produce portable (bio)sensors in a reliable, low cost, rapid, and even facile-to-implement area with inadequate resources. Herein, this work outlines the latest advancement of carbon dots nanostructures on smartphone for onsite detecting of agri-food pollutants. Particularly, we afford a summary of numerous approaches applied for target molecule diagnosis (pesticides, mycotoxins, pathogens, antibiotics, and metal ions), for instance microscopic imaging, fluorescence, colorimetric, and electrochemical techniques. Authors tried to list those scaffolds that are well-recognized in complex media or those using novel constructions/techniques. Lastly, we also point out some challenges and appealing prospects related to the enhancement of high-efficiency smartphone based carbon dots systems. [ABSTRACT FROM AUTHOR]

Magnetic covalent organic frameworks are new emerging materials which, besides many other applications, have found unique applications in analytical chemistry as separating media and adsorbents. They have outstanding features such as special morphology, chemical and thermal stability, high adsorption capacity, good magnetic response, high specific surface area, uniform pore size distribution, strong π-π interactions with analytes and high reusability that makes reported studies on their properties and applications increased in the recent years. After discussing the methods of synthesis of MCOFs with different geometries that cause their special physic-chemical properties, this review focuses on their high potential which has been exhibited in various applications in extraction and pre-concentration of different analytes such as organic compounds, heavy metal ions and biological samples. The article also highlights the applications of magnetic covalent organic frameworks in other chemical analysis such as adsorbent and being used in sensors. [ABSTRACT FROM AUTHOR]

Chirality has an important impact on chemical and biological research, as most active substances are chiral. In recent decades, metal–organic frameworks (MOFs), which are assembled from metal ions or clusters and organic linkers via metal–ligand bonding, have attracted considerable scientific interest due to their high crystallinity, exceptional porosity and tunable pore sizes, high modularity, and diverse functionalities. Since the discovery of the first functional chiral metal–organic frameworks (CMOFs), CMOFs have been involved in a variety of disciplines such as chemistry, physics, optics, medicine, and pharmacology. The introduction of defect engineering theory into CMOFs allows the construction of a class of defective CMOFs with high hydrothermal stability and multi-stage pore structure. The introduction of defects not only increases the active sites but also enlarges the pore sizes of the materials, which improves chiral recognition, separation, and catalytic reactions, and has been widely investigated in various fields. This review describes the design and synthesis of various defective CMOFs, their characterization, and applications. Finally, the development of the materials is summarized, and an outlook is given. This review should provide researchers with an insight into the design and study of complex defective CMOFs. [ABSTRACT FROM AUTHOR]

The column performance of silica‐coated, amino‐functionalized, superparamagnetic nanoparticles co‐integrated with Cynodon dactylon and Murraya koenigii plant extracts for the removal of CuII ions was evaluated. The co‐integrated nanoparticles were used as sorbent materials in fixed‐bed column studies, and the effects of inlet concentration, adsorbent bed depth, and flow rate were analyzed. Breakthrough time was calculated for various CuII inlet concentrations, depths of the adsorbent bed, and volumetric flow rates. Models such as Thomas, Yoon‐Nelson, and the bed depth model were evaluated to determine the experimental fit. The maximum breakthrough time for CuII ions of 1200 min was attained for a CuII inlet concentration of 100 mg L–1, sorbent bed depth of 3 cm, and volumetric flow rate of 1 mL min–1. [ABSTRACT FROM AUTHOR]

In the presented work, magnetic alginate (MA) beads were prepared and activated with epichlorohydrin and then functionalized with agmatine ligands (MA-A). The materials were analyzed by FTIR, SEM, XRD, and BET methods. The adsorption capacity of the MA-A for U(VI) was 451.4 mg/g. The Langmuir isotherm model well described the experimental data for the adsorption of U(VI) ions. The second-order kinetic model data proposed that the adsorption of U(VI) ions preferred the chemisorption mechanism. The adsorption enthalpy of the MA-A beads for U(VI) ions was 35.4 kJ/mol. After seven cycles of use, the adsorption capacity of MA-A beads was not significantly changed for U(VI) ions. Finally, the functionalization of MA beads with agmatine ligand can be a good candidate for applications for environmental technologies to remove metal ions. [ABSTRACT FROM AUTHOR]

Despite the considerable potential of immune checkpoint blockade (ICB) therapy in treating various cancer types, it faces several challenges, of which the constrained objective response rate and relatively short duration of response observed in patients with cancer are the most important. This study introduces an injectable temperature-sensitive hydrogel, Pluronic F-127 (PF-127)@MnCl 2 / alginate microspheres (ALG-MS)@MgCl 2 , that enhances the therapeutic efficacy of programmed cell death-ligand 1 (PD-L1) in cancer cells. The hydrogel material used in this study facilitated the rapid release of a significant amount of manganese ions (Mn2+) and the gradual and sustained release of magnesium ions (Mg2+) within the tumor microenvironment. This staged release profile promotes an immune microenvironment conducive to the cytotoxicity of CD8+ T cells and natural killer cells, thereby enhancing the efficacy of ICB therapy. Furthermore, the PF-127@MnCl 2 /ALG-MS@MgCl 2 composite hydrogel exhibits the ability to convert drug-resistant tumor ("cold tumor") with a low PD-L1 response to a "hot tumor" with a high PD-L1 response. In summary, the PF-127@MnCl 2 /ALG-MS@MgCl 2 hydrogel manipulates the immune microenvironment through the precise discharge of Mg2+ and Mn2+, thus, augmenting the efficacy of ICB therapy. Enhancing the effectiveness of immune checkpoint blockade therapy can be achieved by manipulating the immune microenvironment by utilizing PF-127@MnCl 2 /ALG-MS@MgCl 2 injectable temperature-sensitive hydrogel. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Sodium ions inside biomolecular condensates experience heterogeneous dynamics. • An integrative 23Na NMR relaxation-based approach is developed. • This approach allows separating contribution of various sodium ion populations. • Three populations of sodium ions with distinct dynamics detected in agarose gels. Metal ions, including biologically prevalent sodium ions, can modulate electrostatic interactions frequently involved in the stability of condensed compartments in cells. Quantitative characterization of heterogeneous ion dynamics inside biomolecular condensates demands new experimental approaches. Here we develop a 23Na NMR relaxation-based integrative approach to probe dynamics of sodium ions inside agarose gels as a model system. We exploit the electric quadrupole moment of spin-3/2 23Na nuclei and, through combination of single-quantum and triple-quantum-filtered 23Na NMR relaxation methods, disentangle the relaxation contribution of different populations of sodium ions inside gels. Three populations of sodium ions are identified: a population with bi-exponential relaxation representing ions within the slow motion regime and two populations with mono-exponential relaxation but at different rates. Our study demonstrates the dynamical heterogeneity of sodium ions inside agarose gels and presents a new experimental approach for monitoring dynamics of sodium and other spin-3/2 ions (e.g. chloride) in condensed environments. [ABSTRACT FROM AUTHOR]

The development of nanomaterials incorporating organic components holds significant importance in addressing the efficient removal of metal ions through adsorption. Hence, in this study, a novel MnFe2O4/chitosan/Schiff base nanocomposite was successfully synthesized by crosslinking MnFe2O4 nanoparticles with functionalized chitosan using a novel Schiff base. The Schiff base was created through the condensation reaction between 2-aminophenol and terephthalaldehyde. Comprehensive characterization of the synthesized nanocomposite was performed through FT-IR, XRD, SEM, and VSM analyses, revealing a less crystalline arrangement compared to pure chitosan, a rough and non-uniform surface morphology, and a reduced magnetization value of 30 emu/g. Furthermore, the synthesized MnFe2O4/chitosan/Schiff base nanocomposite was working as an adsorbent for the effective disposal of Zn(II) ions from aqueous solutions. The synthesized nanocomposite exhibited a maximum sorption capacity of 289.86 mg/g for Zn(II) ions. Additionally, the results indicated that the removal of Zn(II) ions by the synthesized nanocomposite was a spontaneous, chemical, and endothermic process, aligning well with the Langmuir isotherm as well as the pseudo-second-order model. Furthermore, at pH 7.5, with a contact duration of 100 min and a temperature of 328 K, the fabricated nanocomposite reached its maximum sorption capacity for Zn(II) ions. The results of this study demonstrate the effectiveness of the newly synthesized MnFe2O4/chitosan/Schiff base nanocomposite in removing Zn(II) ions from aqueous media. The novel synthesis approach and the high adsorption capacity of 289.86 mg/g underscore the potential of this composite for practical applications in industrial wastewater treatment. The dual removal mechanism involving electrostatic attraction and complexation processes further enhances its utility, making it a valuable contribution to the field of environmental remediation. [ABSTRACT FROM AUTHOR]

A magnetic perovskite-spinel oxide nanocomposite synthesized through a sol–gel self-combustion process is used for the first time as an adsorbent to remove toxic heavy metals (i.e., Pb2+). The synthesized LaFeO3:CoFe2O4 ((LFO)1:(CFO)x) (x = 0.11–0.87) nanocomposites possess good stability, abundant oxygenated active binding sites, and unique structural features, making them suitable for removing divalent Pb2+ ions. Scanning electron microscopy, X-ray diffraction, BET surface area, magnetization measurements, zeta-potential analyses, and X-ray photoelectron spectroscopy were used to analyze the nanocomposites, and their structural changes after Pb2+ ions adsorption. Batch tests confirmed that (LFO)1:(CFO)x efficiently removes Pb2+ from water with a maximum adsorption capacity of 105.96 mg/g. The detailed quantitative study indicates that the interaction of hydroxyl groups with Pb2+ ions occurs through electrostatic interactions and complex formation. We also demonstrate a new ring-magnetic separator system that allows magnetic separation of the toxic ions at a higher speed compared to traditional block magnets. The unique structure, high porosity, large specific surface area, and oxygenated functional groups of (LFO)1:(CFO)x nanocomposites make them promising materials for removal of heavy metal ions and possibly other environmental pollutants. This study provides a new approach to preparing nanocomposites of magnetic spinel ferrites with perovskite oxides for environmental applications. [ABSTRACT FROM AUTHOR]

In this investigation, the fluorescent poly(N‐hydroxyethyl morpholine acrylate) (PHEMA) and poly(N‐hydroxypropyl morpholine acrylate) (PHPMA) are prepared and applied as fluorescent probes for the specific detection of Cu2+ ions. Far different from the non‐fluorescent monomer, PHEMA and PHPMA emit a strong fluorescence at 410 nm due to the intramolecular aggregation of morpholine structures along macromolecular chains in the polymerization, indicating polymerization‐induced emission (PIE). The fluorescent emission of PHPMA shows the dependence on external factors including solution concentration, excitation wavelength, solvent, and pH value. PHPMA specifically detects Cu2+ ions even in the presence of 16 common metal ions and 6 anions, with an LOD of 0.077 µM. In the fluorescent quenching, the O atom from ─C═O and N atom from morpholine moiety on the PHPMA chain participate in the complexation with Cu2+ ions with the ratio of the structural unit and Cu2+ ion of 2:1, leading to the dynamic quenching of PHPMA solution. As for the application, PIE‐active PHPMA is easily made into a portable semi‐quantitative filter paper with recyclability. In brief, the PIE‐active PHPMA synthesized in this study can be used as a promising material for the specific detection of Cu2+ ions in industry, agriculture, and medicine fields. [ABSTRACT FROM AUTHOR]

Inorganic–organic hybrid materials that combine both Polyoxometalates (POMs) and metal ion coordinating subunits (CSUs) represent promising multifunctional materials. Though their individual components are often biologically active, utilization of hybrid materials in bioassays significantly depends on the functionalization method and thus resulting stability of the system. Quite intriguingly, these aspects were very scarcely studied in hybrid materials based on the Wells–Dawson POM (WD POM) scaffold and remain unknown. We chose two model WD POM hybrid systems to establish how the functionalization mode (ionic vs. covalent) affects their stability in biological medium and interaction with nucleic acids. The synthetic scope and limitations of the covalent POM-terpyridine hybrids were demonstrated and compared with the ionic Complex-Decorated Surfactant Encapsulated-Clusters (CD-SECs) hybrids. The nature of POM and CSU binding can be utilized to modulate the stability of the hybrid and the extent of DNA binding. The above systems show potential to behave as model cargo-platforms for potential utilization in medicine and pharmacy. [ABSTRACT FROM AUTHOR]

Thiophene, a heterocyclic compound characterized by a five-membered ring comprising four carbon atoms and one sulfur atom, has garnered significant attention in recent research due to its versatile applications in medicinal and chemosensing fields. Thiophene derivatives formed complexes with various transition metals. These complexes exhibit promising anti-inflammatory, anticancer, antibacterial, antifungal and other biological properties. Certainly, the complexation phenomenon involving thiophene derivatives can be effectively used for the recognition of various cations. Thiophene-based compounds can act as selective ligands, forming stable complexes with specific heavy metal ions. This property has significant implications for environmental monitoring, industrial safety, and public health, as the presence of heavy metal ions beyond permissible levels can lead to detrimental effects. This paper explored the versatile applications of thiophene derivatives, investigating their chemosensing potential for the determination of various metal ions covering the period from 2018 to 2024. Thiophene derivatives serve as versatile ligands for metal ions and exhibit fluorescence and colorimetric changes for selective detection of metal ions. Additionally, this study also explores the anticancer efficacy demonstrated by metal complexes derived from thiophene, with a specific emphasis on those formed with platinum-group metals (Ir(III), Ru(II), Ru(III), Rh, Os(II), Os(IV), Pd(II), Pt(II)). [ABSTRACT FROM AUTHOR]

This study describes the development of a multifunction chromoionophoric probe‐based nano‐conjugate material for the colorimetric determination, recovery, and removal of palladium and cobalt ions (Pd(II) and Co(II)) ions from electronic wastes and electroplating wastewater. The chromoionophoric probe‐based nano‐conjugate material was prepared using a building‐block approach by anchoring the 4‐[(E)‐(2‐hydroxyphenyl)diazenyl]‐1‐nitrosonaphthalen‐2‐ol (HDN) organic chromoionophoric probe onto nano‐spherical silica material carrier. The prepared materials were characterized using different techniques, such as TEM, SEM XRD, and BET. The HDN chromoionophoric probe‐based nano‐conjugate material was evaluated for its effectiveness in detecting and removing Pd(II) and Co(II) ions from electronic wastes and electroplating wastewater by testing various parameters such as pH, sensing system temperature, reaction kinetic, nano‐conjugate material amount, stability of the chromoionophoric probe‐based nano‐conjugate material and the existence of other coexisting metal ions. The HDN chromoionophoric probe‐based nano‐conjugate material demonstrated high selectivity and sensitivity for the colorimetric ion‐sensing of Pd(II) and Co(II) ions, with a detection limit of 7.18 and 208 nM, respectively. The method displayed optimal sensing at pH levels of 6.0 and 8.0 for Pd(II) and Co(II) ions, respectively, and the presence of other metal ions did not meaningfully influence the performance of the ion‐detection due to the powerful ability of the chromoionophoric probe‐based nano‐conjugate material. The adsorption capacity of the chromoionophoric probe‐based nano‐conjugate material towards Pd(II) and Co(II) ions was investigated and the outcomes were 163.40 and 128.57 mg/g, respectively. The chromoionophoric probe‐based nano‐conjugate material could be regenerated by eluting the adsorbed Pd(II) and Co(II) ions with 0.15 M HCl solution. In addition, the material could be reused multiple times, with almost no decrease in its initial performance after regeneration. Based on the findings, the chromoionophoric probe‐based nano‐conjugate material shows potential for environmental recovery, removal, and detection of Pd(II) and Co(II) ions from electronic wastes and electroplating wastewater, indicating its potential as a multi‐function solution for environmental concerns and issue and could be even commercialized and used at a larger scale. [ABSTRACT FROM AUTHOR]

Human amylin (hIAPP) is found in the form of amyloid deposits within the pancreatic cells of nearly all patients diagnosed with type 2 diabetes mellitus (T2DM). However, rat amylin (rIAPP) and pramlintide - hIAPP analogs - are both non-toxic and non-amyloidogenic. Their primary sequences exhibit only slight variations in a few amino acid residues, primarily concentrated in the central region, spanning residues 20 to 29. This inspired us to study this fragment and investigate the impact on the aggregation properties of substituting residues within the central region of amylin and its analogs. Six fragments derived from amylin have undergone comprehensive testing against various metal ions by implementing a range of analytical techniques, including Nuclear Magnetic Resonance (NMR) spectroscopy, Thioflavin T (ThT) assays, Atomic Force Microscopy (AFM), and cytotoxicity assays. These methodologies serve to provide a thorough understanding of how the substitutions and interactions with metal ions impact the aggregation behavior of amylin and its analogs. [ABSTRACT FROM AUTHOR]

Porous materials are excellent candidates for water remediation in environmental issues. However, it is still a key challenge to design efficient adsorbents for rapid water purification from various heavy metal ions‐contaminated wastewater in one step. Here, two robust nitrogen‐rich covalent organic frameworks (COFs) bearing terpyridine units on the pore walls by a “bottom‐up” strategy are reported. Benefitting from the strong chelation interaction between the terpyridine units and various heavy metal ions, these two terpyridine COFs show excellent removal efficiency and capability for Pb2+, Hg2+, Cu2+, Ag+, Cd2+, Ni2+, and Cr3+ from water. These COFs are shown to remove such heavy metal ions with >90% of contents at one time after the aqueous metal ions mixture is passed through the COF filter. The nitrogen‐rich features of the COFs also endow them with the capability of capturing iodine vapors, offering the terpyridine COFs the potential for environmental remediation applications. [ABSTRACT FROM AUTHOR]

A new modified cellulose with diaminoguanidine (Cel-Gua) synthesized for specific recovery of Cu (II), Cd (II), and Hg (II) from the alum sample. Cellulose was silanized by 3-chloropropyltrimethoxysilane and then was modified with diaminoguanidine to obtain N-donor chelating fibers. Fourier transform-infrared spectroscopy, scanning electron microscopy, X-ray diffraction, zeta potential, electrons disperse X-ray analysis, elemental analyses (C, H and N), and thermogravimetric analysis were used for characterization. Factors influencing the adsorption were thoroughly examined. Under the optimal conditions, the Cel-Gua sorbent displayed maximum adsorption capacities of 94.33, 112.10 and 95.78 mg/g for Cu (II), Cd (II), and Hg (II), respectively. The sorption process of metal ions is equipped by kinetic model PSO and Langmuir adsorption isotherm. The calculated thermodynamic variables confirmed that the adsorption of Cu (II), Cd (II) and Hg (II) by Cel-Gua sorbent is a spontaneous and exothermic process. In our study, we used the molecular operating environment software to conduct molecular docking simulations on the Cel-Gua compound. The results of the docking simulations showed that the Cel-Gua compound displayed greater potency and a stronger affinity for the Avr2 effector protein derived from Fusarium oxysporum, a fungal plant pathogen (code 5OD4). The adsorbent was stable for 7 cycles, thus allowing its safe reutilization. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Poly‐NHC‐based organometallic assemblies 3‐PF6, 3‐SbF6 and 3‐OTf were obtained and verified by NMR spectroscopy, ESI mass spectrometry and single‐crystal X‐ray diffraction analyses. Controllable structural interconversion was observed between the poly‐NHC‐based organometallic assemblies and their self‐aggregated dimers in solution affected by concentration, solvent and metal ion. 1H NMR spectra of assembly 3‐PF6 in CD3CN at different concentrations demonstrated controllable structural interconversion, and 19F NMR spectrum of assembly 3‐PF6 at high concentration further evidenced the presence of the free hexafluorophosphate anion and encapsulated hexafluorophosphate anion for its two sets of signals. In addition, single‐crystal X‐ray diffraction analysis provided clear evidence that in the solid state, two assemblies 3‐PF6 were vertically stuck, forming a self‐aggregated dimer with an encapsulated hexafluorophosphate anion. Investigating the reversible structural interconversion is beneficial for revealing the intrinsic nature on the atom level and paving the way to design the stimuli‐responsive functional system. [ABSTRACT FROM AUTHOR]

The maximum permissible concentration (m.p.c.) of Cu2+ ions in drinking water, as set by the World Health Organization (WHO) is m.p.c. (Cu2+)WHO = 30 × 10−6 m, whereas the US Environmental Protection Agency (EPA) establishes a more restrictive value of m.p.c. (Cu2+)EPA = 20 × 10−6 m. Herein, for the first time ever, a family of m.p.c. (Cu2+) "visual" pass/fail sensors is developed based on water‐soluble lanthanide‐containing single‐chain nanoparticles (SCNPs) exhibiting an average hydrodynamic diameter less than 10 nm. Both europium (Eu)‐ and terbium (Tb)‐based SCNPs allow excessive Cu2+ to be readily detected in water, as indicated by the red‐to‐transparent and green‐to‐transparent changes, respectively, under UV light irradiation, occurring at 30 × 10−6 m Cu2+ in both cases. Complementary, dysprosium (Dy)‐based SCNPs show a yellow color‐to‐transparent transition under UV light irradiation at ≈15 × 10−6 m Cu2+. Eu‐, Tb‐, and Dy‐containing SCNPs prove to be selective for Cu2+ ions as they do not respond against other metal ions, such as Fe2+, Ag+, Co2+, Ba2+, Ni2+, Hg2+, Pb2+, Zn2+, Fe3+, Ca2+, Mn2+, Mg2+, or Cr3+. These new m.p.c. (Cu2+) "visual" pass/fail sensors are thoroughly characterized by a combination of techniques, including size exclusion chromatography, dynamic light scattering, inductively coupled plasma‐mass spectrometry, as well as infrared, UV, and fluorescence spectroscopy. [ABSTRACT FROM AUTHOR]

Background: Metal ions play vital roles in regulating various biological systems, making it essential to control the concentration of free metal ions in solutions during experimental procedures. Several software applications exist for estimating the concentration of free metals in the presence of chelators, with MaxChelator being the easily accessible choice in this domain. This work aimed at developing a Python version of the software with arbitrary precision calculations, extensive new features, and a user-friendly interface to calculate the free metal ions. Results: We introduce the open-source PyChelator web application and the Python-based Google Colaboratory notebook, PyChelator Colab. Key features aim to improve the user experience of metal chelator calculations including input in smaller units, selection among stability constants, input of user-defined constants, and convenient download of all results in Excel format. These features were implemented in Python language by employing Google Colab, facilitating the incorporation of the calculator into other Python-based pipelines and inviting the contributions from the community of Python-using scientists for further enhancements. Arbitrary-precision arithmetic was employed by using the built-in Decimal module to obtain the most accurate results and to avoid rounding errors. No notable differences were observed compared to the results obtained from the PyChelator web application. However, comparison of different sources of stability constants showed substantial differences among them. Conclusions: PyChelator is a user-friendly metal and chelator calculator that provides a platform for further development. It is provided as an interactive web application, freely available for use at https://amrutelab.github.io/PyChelator, and as a Python-based Google Colaboratory notebook at https://colab.research.google.com/github/AmruteLab/PyChelator/blob/main/PyChelator_Colab.ipynb. [ABSTRACT FROM AUTHOR]

The development of modern industry will generate more and more waste containing metal ions. It is necessary to take appropriate measures to recover these ions, whether from the perspective of environmental protection or improving economic benefits. So far, scientists have studied many methods for recovering metal ions. Among these methods, adsorption and membrane separation have received widespread attention due to their own characteristics. Combining adsorption and membrane separation methods can better leverage their respective advantages to improve the ability of recovering metal ions. This review, therefore, focuses on the synergistic recovery of metal ions by adsorption and membrane separation methods. This article first briefly explains the theoretical principles of membrane separation and adsorption synergy, and then focuses on several technologies that have received attention in different chapters. In these chapters, membrane technology is briefly introduced, followed by the situation and progress of synergistic application with adsorption technology. Then, the article compares and elaborates on the advantages and disadvantages of the above technologies, and finally summarizes and looks forward to these technologies being used to solve the difficulties and challenges in industrial application. [ABSTRACT FROM AUTHOR]

Medium-density fiberboard (MDF) waste generation has increased steadily over the past decades, and therefore, the investigation of novel methods to recycle this waste is very important. The potential of repurposing MDF waste as an adsorbent for the treatment of Cd(II), Cu(II), Pb(II), and Zn(II) ions in water was investigated using MDF offcuts. The highest adsorption potential in single-metal ion solution systems was observed for Pb(II) ions. The experimental data of Pb(II) ions fit well with the Freundlich isotherm and pseudo-second-order kinetic models. Complexation and electrostatic interactions were identified as the adsorption mechanisms. The adsorption behavior of multi-metal ion adsorption systems was investigated by introducing Cd(II) ions as a competitive metal ion. The presence of the Cd(II) ions reduced the adsorption potential of Pb(II) ions, yet the preference for the Pb(II) ions remained. Regeneration studies were performed by using 0.1 M HCl as a regeneration agent for both systems. Even though a significant amount of adsorbed metal ions were recovered, the adsorption potential of the MDF was reduced in the subsequent adsorption cycles. Based on these results, MDF fines have the potential to be used as an economical adsorbent for remediation of wastewater containing heavy metal ions. [ABSTRACT FROM AUTHOR]

Presently, the main cause of pollution of natural water resources is heavy metal ions. The removal of metal ions such as nickel (Ni2+) and cadmium (Cd2+) has been given considerable attention due to their health and environmental risks. In this regard, for wastewater treatment containing heavy metal ions, graphene oxide (GO) nanocomposites with metal oxide nanoparticles (NPs) attained significant importance. In this study, graphene oxide stacked with copper oxide nanocomposites (GO/CuO-NCs) were synthesized and characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and atomic force microscopy (AFM) analytical procedures. The prepared GO/CuO-NCs were applied for the removal of Ni2+ and Cd2+ ions from a binary metal ion system in batch and continuous experiments. The obtained results revealed that GO/CuO-NCs exhibited the highest removal efficiencies of Ni2+ (89.60% ± 2.12%) and Cd2+ (97.10% ± 1.91%) at the optimum values of pH: 8, dose: 0.25 g, contact time: 60 min, and at 50 ppm initial metal ion concentration in a batch study. However, 4mL/min flow rate, 50 ppm initial concentration, and 2 cm bed height were proved to be the suitable conditions for metal ion adsorption in the column study. The kinetic adsorption data exhibited the best fitting with the pseudo- second-order model. The adsorption isotherm provided the best-fitting data in the Langmuir isotherm model. This study suggested that the GO/CuO nanocomposites have proved to be efficient adsorbents for Ni2+ and Cd2+ ions from a binary metal system. [ABSTRACT FROM AUTHOR]

The pollution of water bodies by heavy metal ions has recently become a global concern. In this experiment, a novel chelating resin, D851-6-AHHA, was synthesized by grafting 6-amino-N-hydroxyhexanamide (6-AHHA) onto the (-CH2N-(CH2COOH)2) group of the D851 resin, which contained a hydroxamic acid group, amide group, and some carboxyl groups. This resin was developed for the purpose of removing heavy metal ions, such as Cr(III) and Pb(II), from water. The findings from static adsorption experiments demonstrated the remarkable adsorption effectiveness of D851-6-AHHA resin towards Cr(III) and Pb(II). Specifically, the maximum adsorption capacities for Cr(III) and Pb(II) were determined to be 91.50 mg/g and 611.92 mg/g, respectively. Furthermore, the adsorption kinetics of heavy metal ions by D851-6-AHHA resin followed the quasi-second-order kinetic model, while the adsorption isotherms followed the Langmuir model. These findings suggest that the adsorption process was characterized by monolayer chemisorption. The adsorption mechanism of D851-6-AHHA resin was comprehensively investigated through SEM, XRD, FT-IR, and XPS analyses, revealing a high efficiency of D851-6-AHHA resin in adsorbing Cr(III) and Pb(II). Specifically, the (-C(=O)NHOH) group exhibited a notable affinity for Cr(III) and Pb(II), forming stable multi-elemental ring structures with them. Additionally, dynamic adsorption experiments conducted using fixed-bed setups further validated the effectiveness of D851-6-AHHA resin in removing heavy metal ions from aqueous solutions. In conclusion, the experimental findings underscored the efficacy of D851-6-AHHA resin as a highly efficient adsorbent for remediating water bodies contaminated by heavy metal ions. [ABSTRACT FROM AUTHOR]

A facilely prepared composite based on Polyvinyl alcohol anchored‐ L‐cysteine (PVA‐L‐CYS) demonstrated efficient functionality in the elimination of heavy metals (Hg, Cr, Pb, and Cd) from working wastewater. The synthesis of the composite was validated through a comprehensive characterization utilizing various analytical techniques to ensure the composite's structural, chemical, and physical properties. At ambient temperature, pH of 4–5.5, interaction time of 15–20 minutes, and concentration of 200 mg/L metal ions, the composite exhibited a maximum retention capacity of 48.5, 25, 45.25, and 44.25 mg/g for Hg, Cr, Pb, and Cd, respectively. Langmuir modeling was establish to be more fitting to the practical results than Freundlich, providing theoretical values of 49.02, 25.97, 46.08, and 44.84 mg/g for Hg, Cr, Pb, and Cd, respectively. The kinetics of PVA‐L‐CYS composite was accurately predicted by model of the pseudo‐first‐order kinetic. Thermodynamic prospects indicated a spontaneous, exothermic, and favorable uptake process at low temperatures. Efficient elution of the heavy metal ions from the overloaded composite was performed using 1 M HNO3. In accordance with WHO and FAO guidelines, the successful elimination of working metal ions from wastewater utilizing the PVA‐L‐CYS composite was demonstrated in a single cycle before discharge into the marine environment. [ABSTRACT FROM AUTHOR]

Thioureas are preferred structures in the disciplines of chemosensors, organic, and pharmaceutical field. Thioureas, a class of tuneable organosulfur compounds, and their derivatives are widely used in both biological and nonbiological fields. These compounds, which include sulfur (S) and nitrogen (N) atoms, have nucleophilic characteristics that assist in intra‐ or intermolecular H‐bonding among the molecules or analytes. Hence, the incorporation of the thiourea moiety into a wide spectrum of organic molecules has resulted in very versatile compounds with widespread applications in a variety of domains. Thiourea derivatives have been frequently produced and researched due to their chemosensing capability. Finally, in this work, a detailed comparison and analysis of the detecting capabilities of thiourea‐based cation sensor is performed. The knowledge gained in this work will be extremely useful in future endeavours to create organic sensors based on Fluorescence (Fl) and colorimetry, for the recognition of physiologically relevant metal ions. [ABSTRACT FROM AUTHOR]

Hg(II), poses a significant threat to both the environment and overall well‐being. The present indicator utilizes anthocyanin extract from roselle (Hibiscus sabdariffa), RSE, and incorporates it into bacterial cellulose nanofibers (BCNF) to detect Hg(II) ions. Through examination of the CIE Lab color variables, it is determined that the binding of Hg(II) leads to a discernible alteration in the color. The visible color changes as the Hg(II) concentration increases. ATR‐FTIR(Attenuated Total Reflectance‐Fourier transform infrared spectroscopy) and SEM(scanning electron microscopy) are utilized to analyze the bacterial cellulose nanofibers containing anthocyanin. The selectivity of the proposed sensor is assessed by conducting experiments with different types of metal ions including Co2+, Al3+, Na+, Ba2+, Ni2+, Mg2+, Cd2+, Pb2+, Fe2+, Fe3+, and Cu2+. The outcomes indicate that the sensor exhibits a remarkable ability to distinguish and respond specifically to Hg(II) ions. This particular sensing technique allows for the precise and reliable detection of Hg(II), with a detection limit of 0.72 ppm, by simply observing with the naked eye. For the effective treatment of a tap water sample, the BCNF‐RSE film provides successful results in the detection of Hg(II) ions. This innovative metallochromic sensor offers a promising solution for the on‐site, cost‐effective, portable, easy to use, and real‐time detection of Hg(II) ions. [ABSTRACT FROM AUTHOR]

The demand for nickel, cobalt, and manganese is increasing owing to their critical role in the performance of lithium-ion batteries. Precipitation is simpler to operate than solvent extraction in the separation of metal ions. In this work, precipitation-based procedures were developed to separate Co(II), Mn(II) and Ni(II) from synthetic chloride solutions. Dimethylglyoxime (DMG) was effective in selectively precipitating Ni(II) from the chloride solutions containing Co(II) and Mn(II). Solution pH greatly affected the precipitation of Ni(II) by DMG. In the first procedure, Ni(II) was first precipitated using DMG from solution with initial pH 6 at a DMG/Ni(II) molar ratio of 3, a reaction time of 30 min and then Co(II) was separated from the filtrate by precipitation with Na2S, with optimal conditions being an initial pH of 6, a Na2S/Co(II) molar ratio of 2 and a reaction time of 15 min. In the second procedure, both Ni(II) and Co(II) was simultaneously precipitated with Na2S, leaving Mn(II) in the filtrate. Then the mixed sulfides of Co(II) and Ni(II) were dissolved by using HCl solution containing NaClO as an oxidizing agent. From the leaching solution, Ni(II) was separated by precipitation with DMG. Optimum conditions for the separation conditions were obtained. In both procedures, the separation degree among the three metal ions was higher than 99%. The developed procedures were simple and effective for the separation of the three metal ions compared to solvent extraction. [ABSTRACT FROM AUTHOR]

Sepsis is a potentially life-threatening condition triggered by pathogens such as bacteria and toxins. In clinical settings, hemoperfusion has been used as a therapeutic technique for the treatment of sepsis to remove pathogens, toxins and other inflammatory mediators from the bloodstream. However, the existing adsorption process of hemoperfusion is not specific to sepsis-related pathogens or toxins, resulting in unsatisfactory removal effectiveness and the lack of capture selectivity. Herein, we developed an ultrasound-responsive asymmetric polymeric microbowl coated with macrophage and red blood cell (RBC) membranes to selectively eliminate pathogens, toxins, and heavy metal ions from blood. Poly(glycidyl methacrylate) spherical microparticles were first synthesized and then eroded using dibutyl phthalate and styrene to form a microbowl structure. This asymmetric structure could provide acoustic radiation pressure gradients to realize orientation motion under non-invasive ultrasound fields with a velocity of 37.14 μm s−1 at 20 Vp–p, which could increase adsorption efficiency in physiological environments by fuel-free programable movements. In addition, the macrophage and RBC membrane coating endowed the microbowl with desired biocompatibility, enhanced blood circulation and the ability to selectively eliminate endotoxins, bacteria and heavy metal ions. Endotoxin removal assay showed that 92.80% of endotoxin was eliminated within 15 minutes. Owing to the affinity between the red blood cell membrane and heavy metal ions, the removal efficiency reached 92.75% and 93.91% for Pb2+ and Hg2+, respectively. Meanwhile, over 90% of S. aureus in the blood was eliminated owing to the selective recognition and adhesion of bacteria by macrophage membrane proteins. Overall, this work on ultrasound-responsive asymmetric polymeric microbowls provides a new insight to eliminate pathogens, toxins and heavy metal ions from the bloodstream for sepsis treatment. [ABSTRACT FROM AUTHOR]

The increasing CO2 emissions and their direct impact on climate change due to the greenhouse effect are environmental issues that must be solved as soon as possible. Metal–organic frameworks (MOFs) are one class of crystalline adsorbent materials that are thought to have enormous potential in CO2 capture applications. In this research, the effect of changing the metal center between Zr(IV), Ce(IV), and Hf(IV), and the linker between BDC and PDC has been fully studied. Thus, the six UiO-66 isoreticular derivatives have been synthesized and characterized by FTIR, PXRD, TGA, and N2 adsorption. We also report the BET surface area, CO2 adsorption capacities, kinetics, and the adsorption isosteric heat (Qst) of the UiO-66 derivatives mentioned family. The CO2 adsorption kinetics were evaluated using pseudo-first order, pseudo-second order, Avrami's kinetic models, and the rate-limiting step with Boyd's film diffusion, interparticle diffusion, and intraparticle diffusion models. The isosteric heats of CO2 adsorption using various MOFs are in the range 20–65 kJ mol−1 observing differences in adsorption capacities between 1.15 and 4.72 mmol g−1 at different temperatures due to the electrostatic interactions between CO2 and extra-framework metal ions. The isosteric heat of adsorption calculation in this report, which accounts for the unexpectedly high heat released from Zr-UiO-66-PDC, is finally represented as an increase in the interaction of CO2 with the PDC linker and an increase in Qst with defects. [ABSTRACT FROM AUTHOR]