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The toughening modification of polybenzoxazine is a crucial approach for expanding its application. However, enhancing the toughness of polybenzoxazine poses challenges in concurrently improving comprehensive properties, such as thermal stability, while reducing the curing temperature. To address this issue, we designed a new polyurethane (CIPU) rich in hydrogen bonding and metal coordination bonding and blended it with benzoxazines to tough polybenzoxazine while enhancing their properties across various aspects. Specifically, the addition of 10% CIPU to benzoxazines increased the toughness of polybenzoxazines by 165.3%, attributed to the relative softness of CIPU and multiple sacrificial bonds. Furthermore, the coordination of free In3+ resulted in a significant enhancement in thermal stability and decrement in curing temperature, evidenced by the increase in residual carbon from 30% to 37% at 800 °C and a decrease in the onset of curing temperature from 246.9 °C to 170.7 °C. This work not only introduces a new system for toughening benzoxazine, but also provides unique insights into hydrogen bonding as well as metal-ligand bonding on toughing thermoset resins.

Carbon Quantum Dots from Natural Sources (NACQDs) is a novel type of carbon-based material that have garnered significant attention due to their remarkable features, including luminescence, photostability, nanoscale size, water solubility, low toxicity, biocompatibility, and cost-effectiveness. The synthesis of NACQDs involves a diverse range of natural sources, such as fruits, foods, beverages, human and animal derivatives, vegetables, leaves, and waste materials. Various synthesis methods, including electrochemical approach, chemical oxidation, hydrothermal carbonization, ultrasonic techniques, microwave-assisted synthesis, solvothermal method, laser ablation technique, thermolysis, and atmospheric plasma-based synthesis, have been explored to tailor the size and properties of NACQDs. Characterization techniques like Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TЕM), ultraviolet absorption, fluorescence properties, and nuclear magnetic resonance (NMR) have provided invaluable insights into the physical and chemical characteristics of NACQDs. This review highlights the immense potential of NACQDs in metal ion sensing applications and underscores the need for further investigation to enhance their reproducibility and precise control over their properties. NACQDs hold great promise as versatile nanomaterials for metal ion sensing and are poised to revolutionize diverse fields, ranging from environmental monitoring to biomedical diagnostics and chemical analysis.

The extensive utilization of bismuth and its derivatives in many industries, such as chemical, semiconductor, pharmaceutical, and cosmetics, leads to their accumulation in wastewater, posing a risk to both human health and the environment. Carbon nanorods (CNR) are fluorescent nanoparticles with an ability to detect various analytes as sensing probes. This study focuses on the production, structure, and chemical composition characterization of silkworm-derived CNR (swCNR) and their ability to detect bismuth ions (Bi3+) and inhibit radicals. The optimum wavelength for exciting the fluorescence of swCNR was 370 nm, and the resulting emission peak was observed at 436 nm. The prepared swCNR showed static fluorescence quenching mechanism-based sensing of Bi3+ ions with a limit of detection of 175 nM and two linear ranges from 0.5 to 5 μM (R2 = 0.9997) and 10–50 μM (R2 = 0.9995). The swCNR demonstrated high selectivity in detecting Bi3+ ions in the spiked river water samples, thus establishing the swCNR's role as a nano fluorescence probe designed for the selective detection of Bi3+ ions among other metal ions. Favorable results for the antiradical ability of swCNR were obtained against hydroxyl, 2,2 diphenyl-1 picrylhydrazyl, and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radicals with scavenging percentages of 15, 32, and 90, respectively. The possible applications of swCNR in the environmental and antioxidant sectors are proposed in this study.

Heat tolerance of fungi is critical for field stability and efficacy of fungal insecticides. Components of the medium, such as carbon source, nitrogen source and metal ions, contribute to the thermotolerance of fungi. In this study, several metal ions were detected to establish their effects on the sporulation and thermotolerance of the blastospores of Cordyceps javanica IF-1106 when cultured in liquid medium. The results showed that metal ions play different roles in sporulation and thermotolerance of the fungi. Mn2+ greatly increased the thermotolerance of the blastospores, and Fe2+ increased the thermotolerance slightly. However, both has no or negative effects on sporulation of the fungi. In the case of Cu2+ and Fe3+, sporulation yield and thermotolerance of the blastospores increased significantly. In addition, intracellular trehalose and mannitol involved in thermotolerance of fungi were extracted and then quantified by ion chromatography. We find that the trehalose and mannitol are higher in the presence of Mn2+, implying that Mn2+ could adjust the intracellular trehalose and mannitol level confers the blastospores with higher tolerance to thermal stress. Further, Response Surface Methodology (RSM) was applied to screen the optimal composition of metal ions. When the formula was MnSO4·H2O 8 mg/L, CuSO4·5H2O 5 mg/L, FeSO4·7H2O 11 mg/L, FeCl3·6H2O 8 mg/L, maximum sporulation yield and GT50 were obtained. Lastly, the virulence of the blastospores to Acyrthosiphon pisum was validated, a higher virulence is achieved with decreased LT50 (2 d) and LC50 (2.37 × 104 blastospores mL−1). In conclusion, thermotolerant blastospores of C. javanica IF-1106 and higher sporulation yield could be achieved by optimizing the metal ions composition, which helps to determine the formula for larger scale fermentation process.

Disulfiram (DSF) is a second-line drug for the clinical treatment of alcoholism and has long been proven to be safe for use in clinical practice. In recent years, researchers have discovered the cancer-killing activity of DSF, which is highly dependent on the presence of metal ions, particularly copper ions. Additionally, free DSF is highly unstable and easily degraded within few minutes in blood circulation. Therefore, an ideal DSF formulation should facilitate the co-delivery of metal ions and safeguard the DSF throughout its biological journey before reaching the targeted site. Extensive research have proved that nanotechnology based formulations can effectively realize this goal by strategic encapsulation therapeutic agents within nanoparticle. To be more specific, this is accomplished through precise delivery, coordinated release of metal ions at the tumor site, thereby amplifying its cytotoxic potential. Beyond traditional co-loading techniques, innovative approaches such as DSF-metal complex and metal nanomaterials, have also demonstrated promising results at the animal model stage. This review aims to elucidate the anticancer mechanism associated with DSF and its reliance on metal ions, as well as to provide a comprehensive overview of recent advances in the arena of nanomedicine based co-delivery strategies for DSF and metal ion in the context of cancer therapy.

ABSTRACT: To improve the thermal gel properties of egg yolk, the effect of several valence metal ions (K+, Ca2+, Mg2+ and Fe3+) with different concentrations (0–0.72%) on the rheological, gel, and structural properties of egg yolk were investigated. Results showed that monovalent and divalent ions were beneficial to the formation of uniform and dense gel network, especially with the addition of 0.72% magnesium ion, which further improved gel hardness, water holding capacity (WHC) and viscoelastic properties, the properties of egg yolk gel increased with the increase of the concentration of mono-bivalent metal ions. Adding ferric ion remarkably increased the average particle size (d4,3) and apparent viscosity of egg yolk, destroying the disulfide bonds and the hydrophobic interactions in gel. Fourier transform infrared spectroscopy (FT-IR) and fluorescence spectra analysis revealed that metal ions promoted the hydrophobic aggregation among egg yolk proteins and induced the transition of protein secondary structure from ordered to disordered. This work will provide a theoretical reference for the development of low salt and nutrient fortified egg yolk products.

Cardiac fibrosis is a major public health problem worldwide, with high morbidity and mortality, affecting almost all patients with heart disease worldwide. It is characterized by fibroblast activation, abnormal proliferation, excessive deposition, and abnormal distribution of extracellular matrix (ECM) proteins. The maladaptive process of cardiac fibrosis is complex and often involves multiple mechanisms. With the increasing research on cardiac fibrosis, redox has been recognized as an important part of cardiac remodeling, and an imbalance in redox homeostasis can adversely affect the function and structure of the heart. The metabolism of metal ions is essential for life, and abnormal metabolism of metal ions in cells can impair a variety of biochemical processes, especially redox. However, current research on metal ion metabolism is still very limited. This review comprehensively examines the effects of metal ion (iron, copper, calcium, and zinc) metabolism-mediated redox homeostasis on cardiac fibrosis, outlines possible therapeutic interventions, and addresses ongoing challenges in this rapidly evolving field.

Metal oxides can be doped by various metal ions to tune the properties. While the migration of metal ions especially extrinsic metal ions in metal oxides still needs to be clarified in order to adjust the composition and the structure of metal oxides properly. Here, 14 kinds of metal oxide powders were utilized to investigate the key factors of Zn ion migration in metal oxide powders experimentally. Results show that chemical reactions and/or phase transitions in metal oxides can hinder the migration of Zn ions in metal oxide powders. Compared with unstable metal oxides, it is easier for Zn ions to pass through stable metal oxides which maintain the same component phases at elevated temperatures. Transition from unstable metal oxide medium to stable metal oxide medium will make the transport of Zn ions in the medium from impossible to possible. These findings are helpful for selecting proper metal oxides in related industries such as battery designing, gas sensor development and so on.

Banana peel (Musa Acuminata) contains cellulose that can be used as a carbon-making material. In this study, the activated carbon from banana peel was modified with magnetite to recover iron metal ions in the solution. The manufacture of carbon from banana peels was done by carbonization at a temperature of 450 °C and activated under alkaline conditions with NaOH. The synthesis of activated carbon magnetite composite used FeCl3 and FeSO4 as precursors. The synthesized material was characterized by TGA, FTIR, XRD, and VSM. The thermal stability of activated carbon has increased after the activation process with NaOH. The magnetite composite has formed with saturation magnetization value (Ms) of 14.06 emu/g which is superparamagnetic material. The acidity of the adsorption system influenced this biosorbent effectiveness for the adsorption of iron metal ions in solution. The most optimal adsorption conditions occurred at a pH 6. The optimal adsorption condition is consistent with the Fe(II) adsorption kinetics model using ACM, namely pseudo-second-order with qe = 10.020 mg g−1. The variations in pH affect the Fe(II) adsorption process with ACM, but the adsorption time did not affect the Fe(II) adsorption process with ACM. The adsorption process of Fe(II) with ACM can run optimally in the range of pH ≥ 6 (base condition). The adsorption process at various pH systems did not affect the structure of the activated carbon magnetite (ACM).

By possessing good thermal stability and minimal overall toxicity, gold nanoparticles (AuNPs) appear to be the most effective of all metal nanoparticles (MNPs). Owing to their rapid and simple synthesis, size and shape effect, large surface area, strong adsorption ability, facile conjugation with analyte, excellent biocompatibility, conductivity, and catalytic properties, AuNPs have been used in the fields of catalysis, environmental remediation, healthcare therapy, etc. These properties are important for the detection of a wide range of analytes of interest, such as metal ions, hazardous pollutants, and so on. Metal ions are essential in an assortment of industries, as well as human biological functions and metabolism, so their detection and monitoring for everyday applications have garnered a lot of attention. AuNP-based sensors are expected to transform the practicalities of sensing and detecting various metal ions due to their tunable surface features. In this short review article, we focus on the application of AuNPs-based nanocomposites in metal ion sensing by employing spectrometry and electrochemical techniques. Additionally, a brief description of computational studies on the interaction of AuNPs-based composites with metal ions, biomolecules, and drugs has also been presented. Finally, we discussed the benefits and drawbacks of AuNPs-based sensors for the analyte of interest sensing using these methodologies, as well as future research possibilities.

The Fe3+-loaded NaBiO3 was prepared for photocatalytic removal of tetracycline hydrochloride (TCH) from swine wastewater. Fe3+ greatly reduced the recombination efficiency of the photoinduced electron–hole pairs of NaBiO3. Moreover, the TCH photocatalytic degradation rate constant of Fe3+-loaded NaBiO3 was two-times higher than that of Vis+NaBiO3 after 100 min of reaction. Fe-NaBiO3 combined with PS (100 mg L−1) favored TCH (10 mg L−1) degradation rate (98.8%) at neutral pH. Moreover, the oxidation system was not inhibited by the fulvic acid, and showed a good photocatalytic stability. The superoxide radicals were the main active species involved in the catalytic degradation.

A simple and low cost method for rapid detection of Pb 2+ was developed in this study using a simple fluorescent probe, biotin-4-fluorescein. The presence of Pb 2+ induced the color change of fluorescein from yellow to pink which can be detected visually by naked eyes. The color change of biotin-4-fluorescein was not observed while testing with other metal ions, such as Fe 3+ , Cu 2+ , Ca 2+ , Co 2+ and Cd 2+ , indicating the selectivity of fluorescein derivative with Pb 2+ . Moreover, the color change was observed at pH above 7.0, and the pink color got more intense when increasing pH. Adding EDTA, a chelating reagent, into the solution of biotin-4-fluorescein/Pb 2+ resulted to the rebound of the color to the original color of free biotin-4-fluorescein. The fluorescence spectra of fluorescein decreased with increasing Pb 2+ concentration, and the quenching was enhanced at higher pH. The association constant (K a ) of 2.00 × 10 4  M -1 was calculated from the fluorescence spectra with the limit of detection (LOD) and the limit of quantitation (LOQ) of 1.38 × 10 -5  M (2.86 ppm) and 4.61 × 10 -5  M (9.55 ppm), respectively. Job's plot analysis indicated 2:1 ratio of binding interaction. Pb 2+ in untreated wastewater was quantified for 24.99 ppm using this method. This quick analysis can be beneficial for the application of lead detection in real sample solutions, such as wastewater from industrial factories., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Deinococcus radiodurans can survive under extreme conditions, including high doses of DNA damaging agents and ionizing radiation, desiccation, and oxidative stress. Both the efficient cellular DNA repair machinery and antioxidation systems contribute to the extreme resistance of this bacterium, making it an ideal organism for studying the cellular mechanisms of environmental adaptation. The number of stress-related proteins identified in this bacterium has mushroomed in the past two decades. The newly identified proteins reveal both commonalities and diversity of structure, mechanism, and function, which impact a wide range of cellular functions. Here, we review the unique and general structural features of these proteins and discuss how these studies improve our understanding of the environmental stress adaptation mechanisms of D. radiodurans.

Mesoporous bioactive glass nanoparticles (MBGNPs) are attracting significant attention as suitable materials for multifunctional biomedical applications. In this study, cerium was incorporated into MBGNPs using two different approaches. In the first approach, cerium was added to the glass system directly during the synthesis, while in the second approach, cerium was added to the as-synthesized MBGNPs via the template ion-exchange method. The influence of the method of synthesis on the physicochemical properties of nanoparticles was examined by SEM, TEM, XRD, FTIR, and N2 adsorption-desorption analyses. The MBGNPs exhibited spheroidal morphology and disordered mesoporous structure. XRD analysis confirmed the amorphous nature of the nanoparticles. The chemical composition was determined by the acid digestion method using ICP-OES. The influence of the synthesis method on the specific surface area, mesoporosity, and solubility of synthesized nanoparticles in Tris/HCl (pH 7.4) and acetate (pH 4.5) buffer has also been studied. The obtained Ce containing MBGNPs were non-cytotoxic toward ​preosteoblast MC3T3-E1 cells in contact with nanoparticles in a concentration of up to 100 ​μg/mL. The anti-inflammatory effect of Ce containing MBGNPs was tested with lipopolysaccharides (LPS)-induced proinflammatory RAW 264.7 macrophage cells. Ce containing MBGNPs decreased the release of nitric oxide, indicating the anti-inflammatory response of macrophage cells. Ce containing MBGNPs also showed antibacterial activity against S. aureus and E. coli. The mentioned features of the obtained MBGNPs make them useful in a variety of biomedical applications, considering their biocompatibility, anti-inflammatory response, and enhanced antibacterial effect.

To improve the thermal gel properties of egg yolk, the effect of several valence metal ions (K + , Ca 2+ , Mg 2+ and Fe 3+ ) with different concentrations (0-0.72%) on the rheological, gel, and structural properties of egg yolk were investigated. Results showed that monovalent and divalent ions were beneficial to the formation of uniform and dense gel network, especially with the addition of 0.72% magnesium ion, which further improved gel hardness, water holding capacity (WHC) and viscoelastic properties, the properties of egg yolk gel increased with the increase of the concentration of mono-bivalent metal ions. Adding ferric ion remarkably increased the average particle size (d 4,3 ) and apparent viscosity of egg yolk, destroying the disulfide bonds and the hydrophobic interactions in gel. Fourier transform infrared spectroscopy (FT-IR) and fluorescence spectra analysis revealed that metal ions promoted the hydrophobic aggregation among egg yolk proteins and induced the transition of protein secondary structure from ordered to disordered. This work will provide a theoretical reference for the development of low salt and nutrient fortified egg yolk products., (Copyright © 2024. Published by Elsevier Inc.)

In transdermal drug delivery system (TDDS) patches, achieving prolonged adhesion, high drug loading, and rapid drug release simultaneously presented a significant challenge. In this study, a PHT-SP-Cu 2+ adhesive was synthesized using polyethylene glycol (PEG), hexamethylene diisocyanate (HDI), trimethylolpropane (TMP), and silk protein (SP) as functional monomers which were combined with Cu 2+ to improve the adhesion, drug loading, and drug release of the patch. The structure of the adhesion chains and the formation of Cu 2+ -p-π conjugated network in PHT-SP-Cu 2+ were characterized and elucidated using different characterization methods including FT-IR, 13 C NMR, XPS, SEM imaging and thermodynamic evaluation. The formulation of pressure-sensitive adhesive (PSA) was optimized through comprehensive research on adhesion, mechanics, rheology, and surface energy. The formulation of 3 wt.% SP and 3 wt.% Cu 2+ provided superior adhesion properties compared to commercial standards. Subsequently, the peel strength of PHT-SP-Cu 2+ was 7.6 times higher than that of the commercially available adhesive DURO-TAK® 87-4098 in the porcine skin peel test. The adhesion test on human skin confirmed that PHT-SP-Cu 2+ could adhere to the human body for more than six days. Moreover, the drug loading, in vitro release test and skin permeation test were investigated using ketoprofen as a model drug, and the results showed that PHT-SP-Cu 2+ had the efficacy of improving drug compatibility, promoting drug release and enhancing skin permeation as a TDDS. Among them, the drug loading of PHT-SP-Cu 2+ was increased by 6.25-fold compared with PHT, and in the in vivo pharmacokinetic analysis, the AUC was similarly increased by 19.22-fold. The mechanism of α-helix facilitated drug release was demonstrated by Flori-Hawkins interaction parameters, molecular dynamics simulations and FT-IR. Biosafety evaluations highlighted the superior skin cytocompatibility and safety of PHT-SP-Cu 2+ for transdermal applications. These results would contribute to the development of TDDS patch adhesives with outstanding adhesion, drug loading and release efficiency. STATEMENT OF SIGNIFICANCE: A new adhesive, PHT-SP-Cu 2+ , was created for transdermal drug delivery patches. Polyethylene glycol, hexamethylene diisocyanate, trimethylolpropane, silk protein, and Cu 2+ were used in synthesis. Characterization techniques confirmed the structure and Cu 2+ -p-π conjugated networks. Optimal formulation included 3 wt.% SP and 3 wt.% Cu 2+ , exhibiting superior adhesion. PHT-SP-Cu 2+ showed 7.6 times higher peel strength than DURO-TAK® 87-4098 on porcine skin and adhered to human skin for over six days. It demonstrated a 6.25-fold increase in drug loading compared to PHT, with 19.22-fold higher AUC in vivo studies. α-helix facilitated drug release, proven by various analyses. PHT-SP-Cu 2+ showed excellent cytocompatibility and safety for transdermal applications. This study contributes to developing efficient TDDS patches., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Flower color diversity is a key taxonomic trait in Meconopsis species, enhancing their appeal as ornamental flowers. However, knowledge of the molecular mechanisms of flower color formation in Meconopsis species is still limited. M. wilsonii subsp. australis (Australis) and M. wilsonii subsp. orientalis (Orientalis) have a developmental stage presenting red-purple flowers, while Orientalis also presents blue coloration at the full-bloom period, making them an important model for exploring the mechanism of blue flower formation in M. wilsonii. In this study, we collected petals from Australis and Orientalis at different developmental stages to compare the coloration differences between the two species and detect the molecular mechanisms of blue color in Orientalis. We identified that cyanidin was the main anthocyanin in the flowers of both species, and the blue color in Orientalis primarily arises from anthocyanins (Cyanidin-3-O-sambubioside). RNA sequencing analysis was performed to detect the gene expression in the anthocyanin biosynthesis pathway, and the results suggested that gene regulation for anthocyanin biosynthesis may not be the direct reason for blue color formation in Orientalis. In addition, the growth solid of Orientalis was rich in Fe and Mg ions, and a large amount of Fe and Mg ions accumulated in the petals of Orientalis. Combined with the gene functional enrichment results, we found that the purple and red-purple colors of these two species were presented by different glycosylation levels of cyanidin, while the violet color of Orientalis might be the results of metalloanthocyanins by Fe and Mg ions, which also relieved the toxicity caused by the high content of Fe and Mg ions in its cells. The environmental adaptation-related genes were highly expressed of in both species, such as adaptation to desiccation, water deprivation, freezing, etc. Our results revealed the coloration differences between Australis and Orientalis and described the molecular mechanisms of blue coloration in Orientalis. The data in our analysis could enrich the genetic resources for M. wilsonii for further studies., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The synthesis, characterization and capacity studies of ion exchange resin capable of coordinating with metal ion are reported. Zeolite was modified with conducting polyaniline by the polymerization of anilinium cation in and out side of zeolite channels and a nanocomposite of polyaniline/zeolite (PANI/zeolite) was obtained by the oxidative polymerization of anilinium cation with the zeolite structure. The product was characterized by UV–visible, FTIR, 1H NMR, XRD, SEM and TGA techniques. From FTIR studies it was obtained that the composite has a high content of PANI. SEM pictures in the present study show that the diameter of the PANI/zeolite nanocomposite is between 300 and 600 nm. Batch adsorption experiments were used to investigate the effect of various experimental parameters on the equilibrium adsorption of chromium(VI) on PANI/zeolite nanocomposite. The adsorption characteristics of the composite toward Cr(VI) in dilute aqueous solution were followed spectrophotometrically. The effect of contact time, size of the sorbent and the concentration of Cr(VI) in solution on the metal uptake behavior of the composite were studied. It has been observed that the capacity of chromium adsorption on PANI/zeolite increases with initial metal concentration, the metal ion adsorption on surfactant is well represented by the Freundlich isotherm.

Rice straw waste was used to extract natural cellulose fibers, which was then chemically converted to cellulose gel. Both extracted cellulose and modified cellulose (gel) were characterized using different techniques and used for biosorption of b+arium, manganese, cobalt, nickel, copper, zinc, and cadmium. Both celluloses' chemical compositions were investigated. The FT-IR, XRD, TEM, and SEM results all support the success of the proposed chemical modification. Because of the increase in pore size within the gel composition, the metal sorption capability of the final chelating material (gel) was greater than that of extracted cellulose. The experimental data were fit to the sorption isotherm models of Langmuir, Freundlich, and Temkin. This new modified biopolymer's behaviour suggested that it could be used as a promising sorbent for cation removal from polluted dye baths and waste water. Furthermore, this modified cellulose was prepared as cheap material extracted from the rise waste which helping in protection of the environment and it was confirm excellent behaviour in the removal heavy metals from their aqueous solution compared to the previous materials reported before., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

A new thermoreversible and tunable hydrogel CS-M with high water content prepared by metal cation (M = Cu 2+ , Zn 2+ , Cd 2+ and Ni 2+ ) and chitosan (CS) was reported. The influence of metal cations on the thermosensitive gelation of CS-M systems were studied. All prepared CS-M systems were in the transparent and stable sol state and could become the gel state at gelation temperature (T g ). These systems after gelation could recover to its original sol state at low temperature. CS-Cu hydrogel was mainly investigated and characterized due to its large T g scale (32-80 °C), appropriate pH range (4.0-4.6) and low Cu 2+ concentration. The result showed that the T g range was influenced and could be tuned by adjusting Cu 2+ concentration and system pH within an appropriate range. The influence of anions (Cl - , NO3 - and Ac - ) in cupric salts in the CS-Cu system was also investigated. Scale application as heat insulation window was investigated outdoors. The different supramolecular interactions of the -NH 2 group in chitosan at different temperatures were proposed to dominate the thermoreversible process of CS-Cu hydrogel., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Metal ions play a crucial role in forming hydrogels, and their effects on fucoidan (FUC): κ-carrageenan (KC) mixed gels were investigated. The results indicated that the FUC: KC mixed gels (FC) were promoted by K + and Ca 2+ but destroyed by Fe 3+ . The gel strength of FC was enhanced by K + and Ca 2+ , with G' and G″ being highest at 50 mmol/L KCl and 25 mmol/L CaCl 2 , respectively. Water mobility was weakened after the addition of KCl and CaCl 2 in accordance with the decrease in T 23 relaxation time (free water, 100-1000 ms). After addition of KCl and CaCl 2 , the FC groups presented a typical three-dimensional network structure in contrast to the lamellar, disordered, and broken structure of FUC. Moreover, the FT-IR spectrum certified the enhancement of hydrogen bonds and the occurrence of electrostatic interactions during gel formation by the red-shift of the OH stretching vibration of the Ca 2+ group and the blue-shift of the COS vibrations. The XRD results confirmed that the binding of Ca 2+ to FC was tighter than that of K + at the same charge content. These results provide a theoretical basis for understanding the interaction mechanism of FC with metal ions., Competing Interests: Declaration of competing interest The authors declare that we do not have any potential conflicts of interest in connection with the work submitted., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The presence of heavy metals in crude oil can create different problems on the oil processing and devices as well as pollution of the environment. Establishment of sample preparation methods for the extraction of metals from crude oil is the bottleneck of a successful determination method due to high hydrophobicity and complexity of crude oil matrix. In this study, a dispersive solid phase extraction procedure was developed for the simultaneous extraction of sixteen metal ions based on in-situ formation of an adsorbent in the sample solution. For this purpose, a suitable amount of dithiooxamide was dissolved in an organic solvent and was injected into the sample solution. By this action, dithiooxamide was re-precipitated in the sample solution and adsorbed the ions. The solid particles were separated and then the ions were eluted by a few microliters of choline chloride: 5-amino-8-hydroxyquinoline deep eutectic solvent under sonication. The presented method was validated and broad linear ranges (7.56-50000 ng g -1 ) were obtained for calibration curves with coefficient of determination ≥0.992. Acceptable limits of detection (0.003-2.32 ng g -1 ) and quantification (0.009-7.56 ng g -1 ) were achieved. Good precision (relative standard deviation less than or equal to 4.3% for intra and inter-day precisions) and acceptable extraction recoveries (66-91%) were also obtained. Seven crude oil samples were analyzed and ten metal ions were determined successfully. The method was compared with the methods reported in literature and it was found that the data obtained by this method were reliable and accurate., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Alzheimer's disease (AD), characterized by the β-amyloid protein (Aβ) deposition and tau hyperphosphorylation, is the most common dementia with uncertain etiology. The clinical trials of Aβ monoclonal antibody drugs have almost failed, giving rise to great attention on the other etiologic hypothesis regarding AD such as metal ions dysmetabolism and chronic neuroinflammation. Mounting evidence revealed that the metal ions (iron, copper, and zinc) were dysregulated in the susceptible brain regions of AD patients, which was highly associated with Aβ deposition, tau hyperphosphorylation, neuronal loss, as well as neuroinflammation. Further studies uncovered that iron, copper and zinc could not only enhance the production of Aβ but also directly bind to Aβ and tau to promote their aggregations. In addition, the accumulation of iron and copper could respectively promote ferroptosis and cuproptosis. Therefore, the metal ion chelators were recognized as promising agents for treating AD. This review comprehensively summarized the effects of metal ions on the Aβ dynamics and tau phosphorylation in the progression of AD. Furthermore, taking chronic neuroinflammation contributes to the progression of AD, we also provided a summary of the mechanisms concerning metal ions on neuroinflammation and highlighted the metal ion chelators may be potential agents to alleviate neuroinflammation under the condition of AD. Nevertheless, more investigations regarding metal ions on neuroinflammation should be taken into practice, and the effects of metal ion chelators on neuroinflammation should gain more attention. Running title: Metal chelators against neuroinflammation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

We report accelerated molecular dynamics simulations of α-Synuclein and its complex with two Cu(II) ions bound to experimentally determined binding sites. Adding two Cu(II) ions, one bound to the N-terminal region and one to the C-terminus, decreases size and flexibility of the peptide while introducing significant new contacts within and between N-terminus and non-Aβ component (NAC). Cu(II) ions also alter the pattern of secondary structure within the peptide, inducing more and longer-lasting elements of secondary structure such as β-strands and hairpins. Free energy surfaces, obtained from reweighting the accelerated molecular dynamics boost potential, further demonstrate the restriction on size and flexibility that results from binding of copper ions., Competing Interests: Declaration of Competing Interest The authors confirm that no conflict of interest exists in this work., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Quantum dots (QDs) have been considered as the promising fluorescent labeling material, which is expected to meet the requirement of high-sensitivity detection in clinical diagnostics. Some common metal ions are known to affect the stability and fluorescence properties of QDs, but scarcely any systematic research has been done about their impacts on QD-based bio-detection. By evaluating the effect of Ca 2+ metal ions on the properties of aqueous QDs, a new metal ion-QD fluorescence signal amplification sensor (i.e., Ca 2+ -QD-fluorescence-linked immunosorbent assay, Ca 2+ -QD-FLISA) has been developed for the detection of inflammatory biomarkers with high sensitivity. Compared with the common QD-FLISA, the detection sensitivity for CRP of Ca 2+ -QD-FLISA was improved by a 4-fold of magnitude to 0.23 ng/mL, and this assay showed good selectivity, high accuracy, and excellent repeatability. The versatility of the QD-FLISA method were also validated by using different metal ion-QD probes (Ca 2+ , Mg 2+ , Ba 2+ , Fe 2+ , and Mn 2+ ) to detect CRP, serum amyloid A (SAA), and procalcitonin (PCT). The significant improvement in detection sensitivity was achieved due to the crosslinking of aqueous QDs by Ca 2+ ions to enhance fluorescence and at the same time promote antigen-antibody binding efficiency. The present study illustrates the versatility of metal ion-QD-FLISA as a simple and effective method to detect a wide range of biomarkers with high sensitivity and accuracy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Hybrid polyionic complexes (HPICs), constructed from double-hydrophilic block copolymers and metal ions, have been largely developed with increasing interest in the past decade in the fields of catalysis, materials science and biological applications. The chemical natures of both blocks are very versatile, but one block should be able to interact with ions, and the second one should be neutral. Many metals have been used to form HPICs, which have, in their simplest architectural form, a core-shell structure of a few tens of nanometers in radius with an external shell made of the neutral block of the copolymer. In this review, we focus our discussion on the stability, shape, size and inner structure of these hybrid micelles. We then describe the most recent applications of HPICs, as reported in the literature, and point out the current challenges, missing structural information and future perspectives for this class of organized structures., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

The objectives of this study were twofold: developing lignosulfonate activated carbon fibers (LACFs) and determining the corresponding metal recovery mechanisms with batch experiments and non-linear modeling. LACFs were developed through electrospinning, followed by CO 2 -based physical activation. Physical and chemical characterizations revealed that the LACF sample that was activated for 60 min exhibited a higher specific surface area (376.54 m 2 /g), larger total pore volume (0.30 cm 3 /g), higher micropore ratio (32%), and more acidic and sulfur functional groups than did the other samples. Cu(II) and Au(III) adsorption behaviors on the LACF could be described with the Freundlich and Langmuir model, respectively. Both systems consist of physisorption and chemisorption, and the mechanisms include electrostatic forces, Van der Walls forces, cation exchange, surface complexation. In particular, Au(III) adsorption was faster, and LACF-Au bonds were stronger due to the additional microprecipitation. Furthermore, the LACF sample could regenerate after three adsorption-desorption cycles. Overall, this study provides the foundation for developing physically activated lignosulfonate carbon and its application in recovering valuable metal ions., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The detection of metal ions and amino acids by the aniline oligomer-based receptor has not been reported yet, to the best of our knowledge. In this study, an efficient multifunctional cation-amino acid sensor (CAS) with aniline moiety and chiral thiourea binding site was synthesized by the reaction of aniline trimer and (S)-(+)-1-phenyl ethyl isothiocyanate. CAS can sense Fe 3+ , Cu 2+ , Ag + ions, and L-tryptophan. These results can be recognized by the naked eye. The appropriate pH range for the quantitative analysis of Fe 3+ , Cu 2+, and Ag + by CAS in DMSO/water (30 vol% water) was evaluated. The interaction between CCS and metal ions was analyzed by 1 H NMR titration. The detection limits of CAS for the Cu 2+ , Ag +, and Fe 3+ were 0.214, 0.099, and 0.147 μM, respectively. Moreover, the CASCu 2+ complex can act as a turn-on fluorescence sensor for L-tryptophan. On the contrary, there is no response upon the addition of other amino acids, such as L-histidine, L-proline, L-phenylalanine, L-threonine, L-methionine, L-tyrosine, and L-cystine to CASCu 2+ complex., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The accumulation and aggregation of amyloid-β (Aβ) are critical factors in the pathogenesis of Alzheimer's disease (AD). Several studies have indicated that metal ions such as Cu 2+ and Zn 2+ play a key role in the formation and stabilization of neurotoxic Aβ aggregates, however the molecular mechanisms underlying Aβ cytotoxicity have not yet been fully elucidated. Previously, we showed that the Aβ-derived fragment peptide (Aβ-FrP), Aβ1-19, altered conformation in the presence of Cu 2+ , inhibiting its digestion by metalloproteinase-7 (MMP-7). In this study we demonstrated that Aβ1-19 did not form aggregates in the presence of Cu 2+ . Therefore, we synthesized a new Aβ-FrP, Aβ1-29, which displayed Cu 2+ -dependent conformational conversion and aggregate formation. Aβ1-29 was cleaved by MMP-7, however this reaction was inhibited in the presence of Cu 2+ in a similar way to Aβ1-19. Interestingly, Aβ1-29 showed conformational conversion and aggregate formation in the presence of Zn 2+ , however this did not confer resistance against MMP-7 cleavage. Moreover, Aβ1-29 induced the apoptotic cell death of neural SH-SY5Y cells in the presence of Cu 2+ but not Zn 2+ . These results suggest that Cu 2+ , unlike Zn 2+ , may play an important role in the aggregation mechanism of Aβ and thus in the pathology of AD., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The study of metal ions in the context of cell signaling has historically focused mainly on Ca 2+ , the second messenger par excellence. But recent studies support an emerging paradigm in which other metals, including magnesium and d-block metals, play a role in signal transduction as well. Armed with the right indicators, fluorescence microscopy offers a unique combination of spatial and temporal resolution perfectly suited to reveal metal transients in real time, while also helping identify possible sources of ion mobilization and molecular targets. With a focus on Mg 2+ , we highlight recent advancements in the development of molecular indicators and imaging strategies for the study of metal ions in signaling. We discuss remaining conceptual and technical challenges in the field, and we illustrate through the case of Mg 2+ how the study of nontraditional ions in signaling is inspiring technological developments applicable more broadly to the study of metals in biology., Competing Interests: Conflict of interest statement Nothing declared., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this work, systematic density functional theory (DFT) calculations were performed to study the interactions of various metal ions (Al 3+ , Fe 3+ , Co 2+ , Ni 2+ , Cu 2+ , and Zn 2+ ) and the clinically useful chelating agent called deferiprone (DFP) at the M05-2X/6-31G(d) level of theory. The thermodynamic parameters of metal-deferiprone complexes were determined in water. Based on the obtained data, the theoretical binding energy trend is as follows: Al 3+ > Fe 3+ > Cu 2+ > Ni 2+ > Co 2+ > Zn 2+ , confirming that [Al(DFP) 3 ] has the most interaction energy. Moreover, Natural bond orbital analysis was employed to determine and analyze the natural charges on different atoms and charge transfer between the metal ions and ligands (oxygen atoms) as well as the interaction energy (E(2)) values. The calculated value of ƩE(2) (donor-acceptor interaction energy) for [Al(DFP) 3 ] complex is higher than other complexes, which is according to energy analysis. To confirm the type of effective interactions and bonding properties in the water, the quantum theory of atoms in molecules (QTAIM) analysis was applied. QTAIM analysis confirmed that the strongest M - O bond is found in the [Al(DFP) 3 ] complex. The calculated topological properties at the bond critical points, such as the ratio of the kinetic energy density to the potential energy density, -G(r)/V(r), electronic energy density, H(r), confirm that M - O bonds in the Al-deferiprone complex are non-covalent, while in other complexes, they are electrostatic and partially covalent., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Photo-responsive materials with tunable properties by multiple stimuli have been widely used as molecular machines, molecular logic gates, optical data storages, etc. In this work, we report a rhodamine B-based photo-responsive system, whose properties could be facilely modulated by metal ions (Zn(II), Ni(II) and Hg(II)). These metal ions endow the complexes (L-Zn, L-Ni and L-Hg) with similar photochromic property but distinctly different photo-induced fluorescence change. Upon UV light irradiation, the spirolactam ring in rhodamine B moiety turned from a close form to an open form, along with enlarged conjugated structure with intense absorbance. Interestingly, fluorescence "turn off", "no change" and "turn on" responses were induced by Zn(II), Ni(II) and Hg(II) respectively upon UV light irradiation. Taking advantage of the prominently different characteristics caused by metal ions, different logic gates were designed by simply varying the inputs of metal ions and UV light. This work provided a new strategy for developing multifunctional photo-responsive materials, which were further beneficial for constructing photo-controlled logic gates with tunable performance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Eastern China is a typical region that suffers from harmful cyanobacterial blooms. Numerous studies have focused on bloom formation mechanisms; however, the detailed mechanisms remained unclear. Our study explored the influence of four metal ions (Ca, Cu, Pb and Cd) on Microcystis aeruginosa to determine their effects on bloom formation. We found that Ca concentrations higher than 100 mg L -1 contributed to cyanobacterial bloom formation. The presence of Ca triggered the anti-oxidation process and promoted the secretion of extracellular polysaccharides, thus inducing aggregation of algal cells and enhancing their buoyancy 2.1-fold more than the control (p＜0.05). The reverse regulation of dissolved CO 2 to bicarbonate by carbonic anhydrase formed a large amount of carbonate and decreased the growth rate by 38-56%. Cu (>0.1 mg L -1 ) presented significant toxicity to algal cells while Pb (>1 mg L -1 ) suppressed the algal growth rate due to the acidic condition. Cd (<0.1 mg L -1 ) exhibited no apparent toxicity to the algae. Furthermore, as the buoyancy increased, Cd was likely to facilitate the formation of cyanobacterial blooms, which needs further research. These findings can provide a theoretical basis for eutrophic lake management and contribute to the development of water quality and wastewater discharge standards., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Solute carrier (SLC) transporters meditate many essential physiological functions, including nutrient uptake, ion influx/efflux, and waste disposal. In its protective role against tumors and infections, the mammalian immune system coordinates complex signals to support the proliferation, differentiation, and effector function of individual cell subsets. Recent research in this area has yielded surprising findings on the roles of solute carrier transporters, which were discovered to regulate lymphocyte signaling and control their differentiation, function, and fate by modulating diverse metabolic pathways and balanced levels of different metabolites. In this review, we present current information mainly on glucose transporters, amino-acid transporters, and metal ion transporters, which are critically important for mediating immune cell homeostasis in many different pathological conditions., (© 2019 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.)

Quantitative structure-property relationship modeling method developed from the quantum four-element concept of electronic attributes is validated by the accurate prediction of the redox potentials, deprotonation constants, stability constants and the maximum biosorption capacity of various metal ions and verification of the toxicological endpoint of soil nematodes and mouse. This approach is an extremely promising tool for rationalizing and predicting the toxicity and mobility of different metals and the emission of carbon dioxide from soil. The results demonstrate that the high fungal toxicity and low ion-humic acid binding of cadmium (2+) and the strong complexation of root exudates, such as oxalic acid, citric acid and malic acid, are most likely to promote carbon release., (Copyright © 2019 Elsevier B.V. All rights reserved.)

With the increasing awareness of environmental protection, the greening of flame retardants has become an inevitable choice for flame retardant technology. Bio-based materials have the advantages of wide source, recyclability and green environmental protection, and have received extensive attention. In this work, chitosan and phytic acid as intumescent flame retardant system and metal ion as a synergist were built on cotton fabrics to achieve efficient flame retardancy by facile dip-pad-dry process. Microscale combustion calorimetry results manifested that the heat release rate values of coated samples were lower than that of uncoated samples. The peak heat release rate and total heat release of uncoated samples were 333.1 W/g and 13.1 kJ/g, while these values of samples coated CH/PA/Ba/PA were 129.1 W/g and 5.4 kJ/g respectively and char residues also were increased sharply owing to the phosphate groups promote the formation of char layer covering the surface of the cotton fabrics, which can prevent heat transfer. Scanning electron microscopy confirmed that there were much more bubbles on the surface of fibers for the coated CH/PA/Ba/PA after horizontal flame tests. The results indicated that the synergy of the intumescent flame retardant system was achieved by the addition of metal ions which could accelerate the produce of a large number of nonflammable gases. Horizontal flame test and limit oxygen index (LOI) test showed that the burning rate and LOI values of samples coated CH/PA/Ba/PA, CH/PA /CH/PA, PA/Ba/PA/Ba were 1.5 mm/s and 22.0, 2.0 mm/s and 20.2 and 2.5 mm/s and 18.0 respectively, compared to 3.3 mm/s and 16.2 of uncoated samples. The samples with intumescent flame retardant system and metal ions (CH/PA/Ba/PA) had best flame retardant performance. Moreover its weight gain (5.2%) was less than that (10.7%) of the sample only with intumescent flame retardant system (CH/PA /CH/PA). The less weight gain had less effect on the softness of cotton fabrics. As a result, the coating is expected to be applied in practice., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Heteroatom doping can endow graphene quantum dots (GQDs) with various new or improved structural, optical and physicochemical properties. In contrast to the widely reported oxygen, nitrogen or sulfur doping in GQDs, simple and scalable synthesis of boron-doped GQDs (B-GQDs) with high yield and quantum yields remains challenge. In this work, B-GQDs are one-step synthesized and serve as the fluorescence probes for the fabrication of sensors towards Fe 3+ ion or phosphate (Pi) as well as biosensor towards cytochrome C (Cyt C). The B-GQDs are facile synthesized using one-step bottom-up molecular fusion between 1,3,6-trinitropyrene and borax in sodium hydroxide under hydrothermal process. The synthesis can be performed using large volume autoclave (500 ml) with a high yield of 71%, indicating possibility for gram-scale production of B-GQDs. The as-prepared B-GQDs exhibit single or bilayer graphene structure, high crystallinity, uniform size, bright (absolute photoluminescence quantum yield of 16.8%) and excitation-independent green fluorescence (maximum excitation wavelength and emission wavelength of 480 nm and 520 nm, respectively). Successful doping of B atoms in the lattice of GQDs enables high selectivity towards Fe 3+ . Based on quenching of fluorescence of B-GQDs by Fe 3+ (turn-off model), detection of Fe 3+ (with limit of detection-LOD of 31.2 nM) and Fe 3+ -rich Cyt C (with LOD of 5.9 μg/ml) are demonstrated. As Pi can recover Fe 3+ -quenched fluorescence of B-GQDs (turn-off-on model), indirect fluorescent detection of Pi is also achieved with LOD of 340 nM. In addition, detection of Fe 3+ , Cyt C and Pi in real samples is achieved., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Quercetin is a flavonoid compound widely found in vegetables, fruits, and medicinal plants. It has carbonyl and phenolic hydroxyl groups in its structure that can easily form complexes with metal ions. In this study, we reacted quercetin in water at 95 °C with five metal trace elements commonly found in plants, namely calcium, magnesium, zinc, iron(III), and copper. Each supernatant was then examined by electrospray ionization-time-of-flight mass spectrometry (ESI-TOF MS). The results showed that quercetin can form complexes with Ca 2+ , Mg 2+ , Zn 2+ , and Cu 2+ in ratios of 2:1, 3:1, and 3:2. Interestingly, after reaction with Fe 3+ in water at 95 °C, not only can quercetin‑iron(III) complexes be formed in ratios of 2:1 and 3:1, but small amounts of quercetin‑iron(II) complexes can also be formed in the same ratios. Furthermore, DNA cleavage experiments showed that when acting alone, quercetin and Cu 2+ have weak or no cleavage effects on DNA, but the complex formed after reaction in hot water cleaves DNA in a time- and concentration-dependent manner. These results indicate that complexes may form between quercetin and a variety of metal trace elements in a water decoction of plants, and that these metal complexes may be the material basis for the health-promoting and therapeutic effects of edible or medicinal plants., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The development of bioactive soft materials that can guide cell behavior and have biomimetic mechanical properties is an active and challenging topic in regenerative medicine. A common strategy to create a bioactive soft material is the integration of biomacromolecules with polymers. However, limited by their complex structures and sensitivity to temperature and chemicals, it is relatively difficult to maintain the bioactivity of biomacromolecules during their preparation, storage, and application. Here, a new kind of bioactive soft material based on the molecular integration of metal ions and polymers is designed and exemplified by a hybrid of magnesium ion (Mg 2+ ) and poly(glycerol-sebacate-maleate) (PGSM-Mg). Mg 2+ was firmly incorporated into PGSM molecules through a complexation interaction as evidenced by X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR). The PGSM matrix provided the soft nature and facile processing of the hybrid, which could serve as an injectable material and be fabricated into elastic porous three-dimensional (3D) scaffolds. The Mg 2+ immobilized in the PGSM chain conferred neuroactivity to the resultant hybrid. PGSM-Mg exhibited adequate biodegradability and a sustained release of Mg 2+ . PGSM-Mg 3D scaffolds promoted the adhesion and proliferation of Schwann cells (SCs) more effectively than poly(lactic-co-glycolic acid) (PLGA) scaffolds. Furthermore, SCs on PGSM-Mg scaffolds expressed significantly more neural specific genes than those on PLGA, PGS, and PGSM, including nerve growth factor (NGF) and neurotrophic factor-3 (NTF3). All these results indicated that Mg 2+ immobilized through molecular integration could efficiently regulate the bioactivity of polymers. In view of the wide availability, diverse bioactivity, and high stability of metal ions, the strategy of molecular coupling of metal ions and polymers is expected to be a new general approach to construct bioactive soft materials. STATEMENT OF SIGNIFICANCE: Bioactive soft materials are designed on the basis of the molecular integration of metal ions and polymers. Immobilized metal ions offer a new way to endow bioactivity to polymers. Different from biomolecules such as proteins and genes, metal ions are quite stable and can resist harsh processing conditions. Further, the polymeric matrix provides the soft nature and facile processing of the hybrid. Different from stiff metal-containing inorganic materials, the hybrid is a biomimetic soft material and can be readily processed just like its polymer precursor under mild conditions. In view of the diversity of metal ions and polymers, this strategy is expected to be a new powerful and general approach to construct bioactive soft materials for a wide range of biomedical applications., (Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

A series of silica gel supported amino-terminated PAMAM dendrimers (SG-G1.0 - SG-G3.0) were used for the removal of Cd(II) and Fe(III) from dimethylsulfoxide (DMSO). Various parameters that influence adsorption behaviors including temperature, contact time, and initial metal ion concentration were studied. The adsorption mechanism was revealed by combining the results of experiment and density functional theory (DFT) calculation. It indicates that the adsorption capacities for Cd(II) and Fe(III) are largest among the metal ions tested. The adsorption capacity of SG-G1.0 - SG-3.0 for Cd(II) and Fe(III) follows the order of SG-G2.0 > SG-3.0 > SG-G1.0. The adsorption isotherm shows the adsorption capacities for both metal ions increases with raising the temperature and initial metal ion concentration. The adsorption isotherm is consistent with Langmuir model and the adsorption process is dominated by chemical adsorption mechanism. Thermodynamic parameters indicates that the adsorption for both Cd(II) and Fe(III) is spontaneous and endothermic. Kinetic adsorption indicates that the adsorption equilibrium times for Cd(II) and Fe(III) is about 200 and 350 min, respectively, which can be described by a pseudo-second-order model and controlled by film diffusion process. FTIR analysis and theoretical calculation revealed that the carbonyl O atoms, secondary amine N atoms, and primary amine N atoms are the primary factor responsible for PAMAM adsorption by forming tetra- and penta-coordinated chelates with metal ions., (Copyright © 2018 Elsevier Inc. All rights reserved.)