Cupric Ion Research Articles

The removal of Cl− from acidic wastewater by Cu2+/VC: Through reduction & precipitation function

Nowadays, recycling as the material for industrial sulfuric acid (H2SO4) has become the development trend for the treatment of the acidic wastewater containing H2SO4. To ensure the quality of the recycled H2SO4, the impurities need to be pre-removed, among which chloride ion (Cl−) is still a big issue. In our previous studies, several methods for the removal of Cl− were proposed, however, a limitation of the requirement for the high concentration of H2SO4 remains to be solved. In this work, an approach for the removal of Cl− by copper ion (Cu2+) and ascorbic acid (VC) from the wastewater containing low concentration of H2SO4 was systematically studied. The removal efficiency of Cl−, the mechanism and the application to the actual wastewater were successively explored. For the wastewater with the H2SO4 concentration below 15 g/L, a Cl− removal efficiency above 85 % was always obtained at the mole ratio of Cu2+, VC and Cl− of 3.5:0.75:1 under room temperature. During the removal of Cl−, Cu2+ was firstly reduced by VC to produce cuprous ion (Cu+), which precipitated with Cl− rapidly, leading to the effective removal of Cl− in the form of cuprous chloride (CuCl).

Synthesis, antioxidant, DNA interaction, electrochemical, and spectroscopic properties of chromene-based Schiff bases: Experimental and theoretical approach

Two chromene-based Schiff base ligands were synthesized by the condensation of 5-hydroxy-2,2-dimethyl-2H-chromene-6-carbaldehyde with 2-aminodiphenylamine and 1,8-diaminonaphthalene: (E)-2,2-dimethyl-6-(((2-(phenylamino)phenyl)imino)methyl)-2H-chromen-5-ol (2) and (E)-6-(((8-aminonaphthalen-1-yl)imino)methyl)-2,2-dimethyl-2H-chromen-5-ol (3). The compounds were characterized by Fourier transform infrared (FT-IR), absorption (UV-Vis) and nuclear magnetic resonance (NMR) spectroscopies, in addition to mass spectrometry (MS) analyses; the results of which were rationalized using density functional theoretical (DFT) calculations. Antioxidant activity of the Schiff bases was determined using the DPPH free radical scavenging and CUPric Ion Reducing Antioxidant Capacity (CUPRAC) assays. Compound 3 (IC50 = 14 μM) showed greater free radical scavenging ability than compound 2 (35 μM), and was also more effective than ascorbic acid and Trolox. DFT studies indicate that the HAT mechanism is favored over SET for DPPH scavenging. Both compounds exhibited stronger Cu(II) ion reducing capacity than Trolox and ascorbic acid with Trolox equivalent activity coefficient (TEAC) values of 2.0 and 1.6 for compounds 2 and 3, respectively. Furthermore, DNA cleavage and binding properties were determined using gel electrophoresis, UV-Vis spectroscopy, and cyclic voltammetry. The compounds showed copper-mediated cleavage of plasmid DNA and strong binding to DNA, with binding constants on the order of 104 M−1. The strength of DNA binding was verified by molecular docking analysis using two DNA models: a B-DNA dodecamer (-8.4 to -9.3 kcal/mol) and a hexamer (-7.8 to -7.9 kcal/mol). Overall, the chromene Schiff bases show promise as antioxidant and DNA binding agents.

Chitosan-Silica Composite Aerogel for the Adsorption of Cupric Ions.

A chitosan-silica hybrid aerogel was synthesized and presented as a potential adsorbent for the purification of cupric ion-contaminated media. The combination of the organic polymer (chitosan), which can be obtained from fishery wastes, with silica produced a mostly macroporous material with an average pore diameter of 33 µm. The obtained aerogel was extremely light (56 kg m-3), porous (96% porosity, 17 cm3 g-1 pore volume), and presented a Brunauer-Emmett-Teller surface area (SBET) of 2.05 m2 g-1. The effects of solution pH, aerogel and Cu(II) concentration, contact time, and counterion on cupric removal with the aerogel were studied. Results showed that the initial pH of the cation-containing aqueous solution had very little influence on the removal performance of this aerogel. According to Langmuir isotherm, this material can remove a maximum amount of ca. 40 mg of cupric ions per gram and the kinetic data showed that the surface reaction was the rate-limiting step and equilibrium was quickly reached (in less than one hour). Thus, the approach developed in this study enabled the recovery of waste for the preparation of a novel material, which can be efficiently reused in a new application, namely water remediation.

Synthesis of hydrophobic CuCl/LaA modified by butyltrichlorosilane towards enhanced CO adsorption under humid environment

Cuprous ion modified molecular sieves have been considered as promising CO adsorbents in gas separation or purification industry. However, it persists as a significant challenge to overcome the unfavorable effect of water vapor in the work environment on gas adsorption and separation. Herein, we propose a synthetic strategy using rare earth element La as an additive to form LaOLa coordination bonds followed by surface silanization treatment to construct a hydrophobic SiOSi barrier to significantly improve the stability of Cu+ under humid atmosphere. By successively introducing La3+ and Cu+ into zeolite 5A, CuCl/LaA adsorbents were prepared via ion exchange and solid dispersion methods. And then by silanization modification using toluene as solvent and butyltrichlorosilane (BTS) as hydrophobic agent, hydrophobic CuCl/LaA-BTS adsorbents were prepared. Dynamic adsorption investigation demonstrated that the as-prepared CuCl/LaA-BTS adsorbents possessed hydrophobic surface and consequently the adsorption capacity of CO was enhanced significantly under humid atmosphere. The CO adsorption breakthrough capacity over CuCl/LaA-BTS attained 0.34 mg/g, which was 5.7 times higher than that of zeolite 5A at 40 °C, atmospheric pressure and a relative humidity of RH = 55 %. Moreover, the CO adsorption capacity of CuCl/LaA-BTS retained 0.31 mg/g after four cycle regenerations. This work provides an effective and novel route for synthesizing highly stable cuprous ion modified zeolite adsorbents.

Imidazole-centred cupric ions sensor: Experimental validation, theoretical understanding, and zebrafish bioimaging

In this study, we have developed an imidazole centered fluorescent probe 3-(2-(2-(5-bromo-2-hydroxyphenyl)-4,5-diphenyl-1H-imidazol-1-yl)thiazol-4-yl)-6-chloro-2H-chromen-2-one (SICT), achieving exceptional selectivity for Cu2+ ion detection. These probes exhibit rapid responsiveness (109 nM detection limit) and strong binding constants (0.214 × 105 M−1). Employing an aqueous ethanol system, we assessed their sensing capabilities through both in vitro and in vivo studies, using zebrafish as our model organism. Notably, the SICT probe displays a high quantum yield of 0.62 and follows a 1:1 binding mechanism with Cu2+ ions, validated by Job's plot and ESI-Mass spectrum analyses. Furthermore, our probe demonstrates minimal cytotoxicity in both in vitro (MDA-MB-231 cells) experiments. These promising results motivate us to apply the SICT probe for intracellular Cu2+ ion tracking in zebrafish embryos, showcasing its potential in diverse fields like biomedicine and environmental monitoring.

Effects of Cupric Ion Adsorption onto the Modified Pineapple Pulp as a Biochar Adsorbent

The cupric ion is toxic for humans and is contained in many industrial wastewater that should be effectively removed with adsorption before discharging into the natural water source. In this study, pineapple pulp was obtained from canned pineapple juice manufacturing for drying (DPP) and carbonization (CPP) for 2 h. at 400 °C as the fine biochar adsorbents. The specific surface area of DPP and CPP were 45.3 and 60.2 m2/g, respectively. A high surface area of the carbonized pineapple pulp as a fine adsorbent was found to effectively cupric ion adsorption capacity, the maximum cupric ion removal efficiency of 83.4% and 41.9 mg/g of adsorption capacity at a pH of 6.0 was attained after 30 minutes to equilibrium reach, initial feed concentration of copper (II) sulfate 5-hydrate (CuSO4 . 5H2O) 250 ppm and temperature 50 °C. From these results can be applied to remove the cupric ion from the wastewater treatment.

Evaluation of Antioxidant Capacity, Anticholinergic and Antidiabetic Activities, and Phenolic Ingredients of Asphodelus aestivus by LC-MS/MS.

Herein, it was aimed to evaluate three different extracts of the plant Asphodelus aestivus in terms of their antioxidant capacity, total phenolic content, flavonoid profile, and anticholinergic and antidiabetic activity. In addition, the phenolic content of the A. aestivus extracts was determined by liquid chromatography-mass spectrometry/mass spectrometry. The results obtained in the antioxidant studies were checked against butylated hydroxyanisole, butylated hydroxytoluene, Trolox, and α-tocopherol antioxidants, which are reference standards. The half-maximal inhibition concentration (IC50 ) values of A. aestivus for 1,1-diphenyl-2-picryl-hydrazyl and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) removal activity were 245.015-285.851 and 285.818-371.563 μg/mL, respectively. Then, the reducing impact of A. aestivus extracts was evaluated by the cupric ion (Cu2+ ), ferric ion (Fe3+ ), and Fe3+ -TPTZ reducing capabilities. Moreover, 0.058, 0.064, and 0.100 μg of gallic acid equivalent of phenolic and 0.500, 1.212, and 2.074 μg of quercetin equivalent of flavonoid contents were determined from 1 mg of ethanol, water, and water-ethanol extracts, respectively. For water-ethanol, ethanol, and water extracts of A. aestivus, IC50 values of 0.062±0.0001, 0.068±0.0002, and 0.090±0.0001 μg/mL against acetylcholinesterase, respectively, were calculated. In addition, against the enzyme α-glucosidase IC50 values of 16.376±0.2216, 18.907±0.3004, and 24.471±0.4929 μg/mL, respectively, were calculated. Extracts showed considerable biological activities thanks to the important molecules they contain.

Different Valence States of Copper Ion Delivery against Triple-Negative Breast Cancer.

Different valence states of copper (Cu) ions are involved in complicated redox reactions in vivo, which are closely related to tumor proliferation and death pathways, such as cuproptosis and chemodynamic therapy (CDT). Cu ion mediated Fenton-like reagents induced tumor cell death which presents compelling attention for the CDT of tumors. However, the superiority of different valence states of Cu ions in the antitumor effect is unknown. In this study, we investigated different valence states of Cu ions in modulating tumor cell death by Cu-chelated cyanine dye against triple-negative breast cancer. The cuprous ion (Cu+) and copper ion (Cu2+) were chelated with four nitrogen atoms of dipicolylethylenediamine-modified cyanine for the construction of Cu+ and Cu2+ chelated cyanine dyes (denoted as CC1 and CC2, respectively). Upon 660 nm laser irradiation, the CC1 or CC2 can generate reactive oxygen species, which could disrupt the cyanine structure, achieving the rapid release of Cu ions and initiating the Fenton-like reaction for CDT. Compared with Cu2+-based Fenton-like reagent, the CC1 with Cu+ exhibited a better therapeutic outcome for the tumor due to there being no need for a reduction by glutathione and a shorter route to generate more hydroxyl radicals. Our findings suggest the precision delivery of Cu+ could achieve highly efficient antitumor therapy.

In vitro research to evaluate the antioxidant effects, inhibiting enzymes, methicillin-resistant Staphylococcus aureus strains of Terminalia catappa extracts

AimContribute to the well-being of the Ivorian population through scientific proof of the use of Terminalia cattapa leaves extracts in traditional medicine. MethodologyThe antioxidative effect of aqueous, water-alcoholic, ethyl acetate and hexane derivatives of Terminalia catappa leaves was measured by six tests: DPPH (2-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)), FRAP (ferric ion reducing antioxidant power), PPBD (phosphomolybdenum), CUPRAC (cupric ion reducing antioxidant capacity) and MCA (metal chelating activity). The inhibition of the activity of five enzymes (acetylcholinesterase, butyrylcholinesterase, tyrosinase, amylase and glucosidase) was also determined. In addition, the broadcast method was used to evaluate impact of the samples on methicillin-resistant Staphylococcus aureus (MRSA) strains. ResultsHighest antioxidant capacity was obtained in the ethanolic sample for DPPH, ABTS, FRAP and PPBD tests. Ethyl acetate sample produced the best CUPRAC and MCA tests. Among inhibitory effect of samples on the five enzymes, aqueous sample showed the strongest anti-acetylCholynesterase and anti-butyrylCholynesterase activity. Best anti-tyrosinase and anti-amylase activity were obtained with the ethanolic sample. Hexane sample obtained the best anti-glucosidase activity while ethanolic and aqueous samples obtained none. All extracts showed no activity on the MRSA strains tested. ConclusionThe chemical compounds present in Terminalia cattapa leaves extracts would not be responsible for the use made in traditional medicine against infections.

Flexible active-site loops fine-tune substrate specificity of hyperthermophilic metallo-oxidases

Hyperthermophilic (‘superheat-loving’) archaea found in high-temperature environments such as Pyrobaculum aerophilum contain multicopper oxidases (MCOs) with remarkable efficiency for oxidizing cuprous and ferrous ions. In this work, directed evolution was used to expand the substrate specificity of P. aerophilum McoP for organic substrates. Six rounds of error-prone PCR and DNA shuffling followed by high-throughput screening lead to the identification of a hit variant with a 220-fold increased efficiency (kcat/Km) than the wild-type for 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) without compromising its intrinsic activity for metal ions. The analysis of the X-ray crystal structure reveals four proximal mutations close to the T1Cu active site. One of these mutations is within the 23-residues loop that occludes this site, a distinctive feature of prokaryotic MCOs. The increased flexibility of this loop results in an enlarged tunnel and one additional pocket that facilitates bulky substrate-enzyme interactions. These findings underscore the synergy between mutations that modulate the dynamics of the active-site loop enabling enhanced catalytic function. This study highlights the potential of targeting loops close to the T1Cu for engineering improvements suitable for biotechnological applications.Graphical

Antioxidant Activities of Stem, Leaves and Fruits Extracts of Pepino (Solanum muricatum Aiton).

<b>Background and Objective:</b> Pepino (<i>Solanum muricatum</i> Aiton), rich with vitamin C and flavonoids, constitutes an abundant source of potent antioxidants. This research was conducted to determine antioxidant activity from three different parts of pepino based on equivalence with ascorbic acid, to analyze the relationship between total phenolic content (TPC) and total flavonoid content (TFC) on antioxidant activities and to determine flavonoid compounds. <b>Materials and Methods:</b> Antioxidant activities were determined using 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) and Cupric Ion Reducing Antioxidant Capacity (CUPRAC) methods. The TPC and TFC were determined by UV-visible spectrophotometry. The correlation between TPC, TFC and antioxidant activity was analyzed using Pearson's method. Flavonoid compound content was performed by HPLC. <b>Results:</b> The ethyl acetate pepino fruit extract expressed the highest antioxidant activity by DPPH and CUPRAC assays. The highest TPC was obtained from the ethyl acetate extract of pepino stem (18.493 g GAE/(100 g)), while the highest TFC was obtained from the hexane extract of pepino leaves (9.541 g QE/(100 g)). <b>Conclusion:</b> The DPPH and CUPRAC assays demonstrated that pepino exhibits potential as a source of natural antioxidants, especially in its fruit part.

Photocatalytic evaluation of disperse purple dye using Polyvinylpyrrolidone capped bare and Cu+2/Fe+3 codoped ZnO nano catalysts

Polyvinylpyrrolidone capped bare zinc oxide and codoped with cupric and ferric ions, have been fabricated by a facile polyol reduction method with ethylene glycol. The as-fabricated nanoparticles were calcinated to control their size and morphology. The fabricated nanoparticles were characterized using various techniques including X-ray diffraction, scanning electron microscopy, energy dispersion X-rays, UV–Vis spectroscopy, and Fourier transform infrared Spectroscopy. The results showed phase pure nanoparticles with wurtzite zinc oxide structure, and a blue shift in absorbance spectrum when zinc oxide was codoped with cupric and ferric ions.The study examined the degradation rate of disperse purple dye using bare and codoped zinc oxide nanoparticles in the solar region. Codoped nanocatalysts showed superior efficiency compared to bare zinc oxide. The kinetic analysis of the dye was conducted, revealing that the degradation of the dye followed a pseudo-first-order kinetics pattern. Furthermore, about 99 % degradation of the dye solution in 110 min by codoped zinc oxide as compared to bare zinc oxide (84 %) under solar light suggests Cu+2/Fe+3 codoped zinc oxide is an emerging tool for environmental remediation.

Intelligent nanoreactor coupling tumor microenvironment manipulation and H2O2-dependent photothermal-chemodynamic therapy for accurate treatment of primary and metastatic tumors

Tumor microenvironment (TME), as the “soil” of tumor growth and metastasis, exhibits significant differences from normal physiological conditions. However, how to manipulate the distinctions to achieve the accurate therapy of primary and metastatic tumors is still a challenge. Herein, an innovative nanoreactor (AH@MBTF) is developed to utilize the apparent differences (copper concentration and H2O2 level) between tumor cells and normal cells to eliminate primary tumor based on H2O2-dependent photothermal-chemodynamic therapy and suppress metastatic tumor through copper complexation. This nanoreactor is constructed using functionalized MSN incorporating benzoyl thiourea (BTU), triphenylphosphine (TPP), and folic acid (FA), while being co-loaded with horseradish peroxidase (HRP) and its substrate ABTS. During therapy, the BTU moieties on AH@MBTF could capture excessive copper (highly correlated with tumor metastasis), presenting exceptional anti-metastasis activity. Simultaneously, the complexation between BTU and copper triggers the formation of cuprous ions, which further react with H2O2 to generate cytotoxic hydroxyl radical (•OH), inhibiting tumor growth via chemodynamic therapy. Additionally, the stepwise targeting of FA and TPP guides AH@MBTF to accurately accumulate in tumor mitochondria, containing abnormally high levels of H2O2. As a catalyst, HRP mediates the oxidation reaction between ABTS and H2O2 to yield activated ABTS•+. Upon 808 nm laser irradiation, the activated ABTS•+ performs tumor-specific photothermal therapy, achieving the ablation of primary tumor by raising the tissue temperature. Collectively, this intelligent nanoreactor possesses profound potential in inhibiting tumor progression and metastasis.

Chemical Content by LC–MS/MS, Antiglaucoma, and Antioxidant Activity of Propolis Samples From Different Regions of Türkiye

Propolis is a sticky substance produced by bees because of the reaction of beeswax, pollen, and bee enzymes. Particularly, their biological activity and chemical content attract attention. Thus, in this study, the total amount of phenolic and flavonoid substances, Fe3+‐Fe2+, Cu2+ (cupric ions reducing activity [CUPRAC]), and Fe3+‐TPTZ (ferric ions reducing antioxidant power [FRAP]) reducing, and DPPH• and ABTS•+ scavenging assays in vitro antioxidant properties of propolis samples obtained from four different provinces of Türkiye were determined. In addition, the chemical content of propolis samples was quantitatively determined by LC–MS/MS, and the antiglaucoma property was revealed by hCAII enzyme inhibition. Propolis samples from Ordu presented the highest amounts of total phenolic and flavonoid content (492.3 ± 5.8 and 96.1 ± 2.1, respectively) and also highest antioxidant activity (DPPH• and ABTS•+ IC50 [μg/mL]: 8.884 ± 0.84 and 4.589 ± 0.80, respectively; Fe+3, CUPRAC, and FRAP: 1.051 ± 0.012, 1.021 ± 0.008, and 0.957 ± 0.007 μg/mL, respectively). hCAII enzyme inhibition was highest in Muş propolis (IC50 [μg/mL]: 8.6) as determined. By LC–MS/MS, 53 different components were screened and 35 bioactive components were determined. According to the results, propolis was found to be a raw material because it contains high concentrations of acacetin, chrysin, caffeic acid, and quinic acid (123.824, 24.759, 47.779, and 16.32 mg analyte/g extract, respectively).

Poor control of oxidative stress index is associated with increased DNA methylation in retinopathy patients of a sample from babylonian population

Abstract Background: Retinopathy is one of almost insidious advanced neuron-vascular complications of diabetes, oneof the most common complications that lead to permanent visual impairment in the middle-aged population. Objectives: The study investigated the association between poor oxidative stress index and DNA methylation. Materials and Methods: The study included 120 participants, of whom 40 were healthy, 40 patients with retinopathy, and 40 non-retinopathy diabetes patients (type 2 diabetes mellitus (T2DM)). The total antioxidant, capacity (TAC) evaluated using Cupric ion reducing antioxidant capacity method. Reactive oxygen species (ROS) was measured using Erel method. Global DNA methylation has measured employing 5 mC% estimating using MethylFlash™ Methylated DNA Quantification Kit. Results: Current investigation indicated significant (P ≤ 0.05) accrue in TAC, ROSs, and oxidative stress index (OSI) in diabetic compared with controls. In addition, a significant (P ≤ 0.05) increase of ROSs and OSI were recorded in retinopathy compared with T2DM patients was reported. The analysis of global DNA methylation revealed that diabetic patients have a significantly (P ≤ 0.05) more 5 mC% as compared with healthy subjects. Also, the present study showed a significant rise in methylation in retinopathy compared as with T2DM patients. Regarding the correlation analysis, the current study conducted significantly (P < 0.05) positive association between DNA methylation and each of the ROSs and OSI. Also, a significant positive correlation was reported between DNA methylation and ROSs and OSI in retinopathy and T2DM. Conclusion: Global DNA methylation has an increased level in patients and could be engaged with emergence and progress of retinopathy in diabetic with poor control of oxidative stress and increased ROSs.

An innovative Schiff-base colorimetric chemosensor for the selective detection of Cu2+ ions and its applications.

A novel Schiff base moiety, (E)-4-(1-hydrazonoethyl)benzene-1,3-diol (2), and 2,4-dihydroxybenzaldehyde were condensed in a 1 : 1 molar ratio to generate 4-((E)-1-(((Z)-2,4dihydroxybenzylidene)hydrazono)ethyl)benzene-1,3-diol (L), which was then characterized using high-resolution mass spectrometry (HRMS), 1H-NMR, 13C NMR, and single-crystal XRD techniques. UV-vis absorbance measurements were used to determine whether the Schiff base could detect the cupric ions more effectively than the other transition metal ions. When Cu2+ ions were involved, a new band was observed at 462 nm. From the Job plot, the binding stoichiometry for the anticipated L : Cu2+ partnership is determined to be 1 : 1. For the purpose of validating structural correlations and absorption data, DFT simulations were performed. Further, docking studies for L indicated high binding affinity for human hemoglobin, providing vital information about the ligand's favorable binding locations inside hemoglobin binding sites and the consequent interactions with HHb. The binding coefficient and limit of detection were found to be 3.02 × 104 M-1 and 42.09 nM, respectively. Reversibility of the complex was seen upon the addition of EDTA to the L-Cu2+ solution, and a colorimetric variation simulating the "INHIBIT" molecular logic gate was seen upon the addition of Cu2+ and EDTA to L. Furthermore, the chemosensor's potential application in the detection of Cu2+ in the solid state by chemosensor L also confirms its usefulness in real-world applications emphasizing its versatility and practical utility.

Cytotoxicity of Sambucus nigra L. on Cancer Cell Line and In Vitro Antioxidant Properties

Objective: Essential oils, free fatty acids, flavonoids, glycosides, phenolic acids, carotenoids, vitamins, and minerals are found in significant quantities in the characteristic chemical composition of Sambucus nigra L. This study aimed to evaluate the antioxidant potential of Sambucus nigra L. Fructus and evaluate the cytotoxicity on the cancer cell line.
 Methods: The Sambucus nigra L. fruits were collected from Yalova Atatürk Horticultural Central Research Institute in September 2021. The ethanol extract was prepared. Antioxidant property of Sambucus nigra L. fruit extracts was evaluated with 2,2-diphenyl-1-picryl-hydrazyl- hydrate (DPPH) radical scavenging activity, Cupric Ion Reducing Antioxidant Capacity (CUPRAC). Also, total phenolic content, total flavonoid content, and total anthocyanin content were calculated. Liver hepatocellular carcinoma cell line (HepG2) was used for cytotoxicity assay and an 2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was applied.
 Results: The total phenolic, total flavonoid contents and total monomeric anthocyanins were 9.75±0.92 mg GAE/ mg fruit extract, 0.07437±0.004 mg quercetin/ mg fruit extract, respectively. 0.45±0.0014 mg catechin/gram of fruit extract and 2.08±0.025 mg Cyanidin-3 glucosides/g fruit extract. CUPRAC and DPPH results showed that Sambucus nigra L. extract has strong antioxidant activity. The results of the cytotoxicity assay indicated that while concentrations of the extract increased, the viability of HepG2 decreased.
 Conclusion: Our findings suggest that the Sambucus fruit extract is particularly rich in antioxidant components that are possibly modulating their beneficial use for hepatocellular malignancies, significantly reducing the number of viable cancer cells and inducing cell death.

Copper nanoparticles production by a novel non-dispersive membrane nanoprecipitation process

This study presents, for the first time, a novel route for producing elemental copper nanoparticles using a non-dispersive membrane nanoprecipitation process based on membrane contactors. Copper sulfate solutions ranging between 0.005 and 0.01 M Cu concentration were circulating through a hydrophobic polypropylene flat-sheet membrane, where hydrazine solutions with 1.84–3.64 M were fed by the other side of the membrane. The gradient of hydrazine concentration between both phases was the driving force that promoted the volatilization and transfer of hydrazine through the membrane pores, then reacting with cupric ions to precipitate elemental copper. The effects of copper concentration, hydrazine concentration, and temperature (20–40 °C) in the particle size distribution were assessed. Smaller nanoparticle sizes were obtained at the lowest copper concentration and the highest hydrazine concentration. Thus, the smallest copper nanoparticles were produced under the highest hydrazine/copper molar ratio, reaching values of around 200 nm. Besides, the precipitates showed a surface plasmon resonance, confirming the presence of elemental copper nanoparticles. Therefore, this study opens a new approach to producing metal nanoparticles with perspectives of application in industrial manufacturing, recovering valuable metals from mining effluent treatment, or even hydrometallurgical processes.

Coumarin Based Hydrazone as an Antioxidant and Sensor for Cupric Ion: Spectroscopic and Computational Studies

AbstractA coumarin based hydrazone (CH) has been synthesised and characterised through 1H NMR, FTIR, UV‐Vis spectroscopy and CHN analysis. Using UV‐Vis and time dependent density functional theory, the antioxidant activity of CH against 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical and sensing properties towards various transition metal ions were studied. CH selectively binds to Cu2+ ion as compared to other transition metal ions such as Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Zn2+. From Benesi‐Hildebrand plot, the binding constant of CH for Cu2+ ion: 6×104 M−1 with lower limit of detection 31 μM is obtained. The CH‐Cu2+ complex is more stable as compared to the free form of the CH molecule. The stoichiometry ratio for CH‐Cu2+ complex is 2 : 1. CH quenches the DPPH radical through proton transfer mechanism with IC50 is 25 μM.

Nanoenabled Intracellular Metal Ion Homeostasis Regulation for Tumor Therapy.

Endogenous essential metal ions play an important role in many life processes, especially in tumor development and immune response. The approval of various metallodrugs for tumor therapy brings more attention to the antitumor effect of metal ions. With the deepening understanding of the regulation mechanisms of metal ion homeostasis in vivo, breaking intracellular metal ion homeostasis becomes a new means to inhibit the proliferation of tumor cells and activate antitumor immune response. Diverse nanomedicines with the loading of small molecular ion regulators or metal ions have been developed to disrupt metal ion homeostasis in tumor cells, with higher safety and efficiency than free small molecular ion regulators or metal compounds. This comprehensive review focuses on the latest progress of various intracellular metal ion homeostasis regulation-based nanomedicines in tumor therapy including calcium ion (Ca2+ ), ferrous ion (Fe2+ ), cuprous ion (Cu+ ), managanese ion (Mn2+ ), and zinc ion (Zn2+ ). The physiological functions and homeostasis regulation processes of ions are summarized to guide the design of metal ion regulation-based nanomedicines. Then the antitumor mechanisms of various ions-based nanomedicines and some efficient synergistic therapies are highlighted. Finally, the challenges and future developments of ion regulation-based antitumor therapy are also discussed, hoping to provide a reference for finding more effective metal ions and synergistic therapies.