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Scorodite (FeAsO

Superparamagnetic iron oxide nanoparticles (SPION) have a great potential in both diagnostic and therapeutic applications as they provide contrast in magnetic resonance imaging techniques and allow magnetic hyperthermia and drug delivery. Though various types of SPION are commercially available, efforts to improve the quality of SPION are highly in demand. Here, we describe a strategy for optimization of SPION synthesis under microfluidics using the coprecipitation approach. Synthesis parameters such as temperature, pH, iron salt concentration, and coating materials were investigated in continuous and segmented flows. Continuous flow allowed synthesizing particles of a smaller size and higher stability than segmented flow, while both conditions improved the quality of particles compared to batch synthesis. The most stable particles were obtained at a synthesis condition of 6.5 M NH

Ferritins are highly conserved supramolecular protein nanostructures that play a key role in iron homeostasis. Thousands of iron atoms can be stored inside their hollow cavity as a hydrated ferric oxyhydroxide mineral. Although phosphate associates with the ferritin iron nanoparticles, the effect of physiological concentrations on the kinetics, structure, and reactivity of ferritin iron cores has not yet been explored. Here, the iron loading and mobilization kinetics were studied in the presence of 1-10 mM phosphate using homopolymer and heteropolymer ferritins having different H to L subunit ratios. In the absence of ferritin, phosphate enhances the rate of ferrous ion oxidation and forms large and soluble polymeric Fe(III)-phosphate species. In the presence of phosphate, Fe(II) oxidation and core formation in ferritin is significantly accelerated with oxidation rates several-fold higher than with phosphate alone. High-angle annular dark-field scanning transmission electron microscopy measurements revealed a strong phosphate effect on both the size and morphology of the iron mineral in H-rich (but not L-rich) ferritins. While iron nanoparticles in L-rich ferritins have spherical shape in the absence and presence of phosphate, iron nanoparticles in H-rich ferritins change from irregular shapes in the absence of phosphate to spherical particles in the presence of phosphate with larger size distribution and smaller particle size. In the presence of phosphate, the kinetics of iron-reductive mobilization from ferritin releases twice as much iron than in its absence. Altogether, our results demonstrate an important role for phosphate, and the ferritin H and L subunit composition toward the kinetics of iron oxidation and removal from ferritin, as well as the structure and reactivity of the iron mineral, and may have an important implication on ferritin iron management

Reaction of 6-nitrochrysene with ethyl isocyanoacetate in the presence of a non-nucleophilic base gave a

Small extracellular vesicles (sEVs) have been increasingly recognized as circulating biomarkers and prognosticators for disease diagnosis. However, the clinical applications of sEVs are seriously limited by the lack of a robust and easy scale-up isolation technique. Herein, the feasibility of a polyphenol-metal three-dimensional (3D) network for label-free sEV isolation was explored. As a proof-of-concept, with tannic acid (TA) as the polyphenolic ligand and Fe(III) as the coordinated metal, the TA-Fe(III) 3D network coating mesoporous silica beads (SiO

Siderophores are synthesized by microbes to facilitate iron acquisition required for growth. Catecholate, hydroxamate, and α-hydroxycarboxylate groups comprise well-established ligands coordinating Fe(III) in siderophores. Recently, a C-type diazeniumdiolate ligand in the newly identified amino acid graminine (Gra) was found in the siderophore gramibactin (Gbt) produced by Paraburkholderia graminis DSM 17151. The N-N bond in the diazeniumdiolate is a distinguishing feature of Gra, yet the origin and reactivity of this C-type diazeniumdiolate group has remained elusive until now. Here, we identify l-arginine as the direct precursor to l-Gra through the isotopic labeling of l-Arg, l-ornithine, and l-citrulline. Furthermore, these isotopic labeling studies establish that the N-N bond in Gra must be formed between the Nδ and Nω of the guanidinium group in l-Arg. We also show the diazeniumdiolate groups in apo-Gbt are photoreactive, with loss of nitric oxide (NO) and H+ from each d-Gra yielding E/Z oxime isomers in the photoproduct. With the loss of Gbt's ability to chelate Fe(III) upon exposure to UV light, our results hint at this siderophore playing a larger ecological role. Not only are NO and oximes important in plant biology for communication and defense, but so too are NO-releasing compounds and oximes attractive in medicinal applications.

Arsenic (As)-bearing water treatment residuals (WTRs) from household sand filters are usually disposed on top of floodplain soils and may act as a secondary As contamination source. We hypothesized that open disposal of these filter-sands to soils will facilitate As release under reducing conditions. To quantify the mobilization risk of As, we incubated the filter-sand, the soil, and a mixture of the filter-sand and soil in anoxic artificial rainwater and followed the dynamics of reactive Fe and As in aqueous, solid, and colloidal phases. Microbially mediated Fe(III)/As(V) reduction led to the mobilization of 0.1-4% of the total As into solution with the highest As released from the mixture microcosms equaling 210 μg/L. Due to the filter-sand and soil interaction, Mössbauer and X-ray absorption spectroscopies indicated that up to 10% Fe(III) and 32% As(V) were reduced in the mixture microcosm. Additionally, the mass concentrations of colloidal Fe and As analyzed by single-particle ICP-MS decreased by 77-100% compared to the onset of reducing conditions with the highest decrease observed in the mixture setups (95%). Overall, our study suggests that (i) soil provides bioavailable components (e.g., organic matter) that promote As mobilization via microbial reduction of As-bearing Fe(III) (oxyhydr)oxides and (ii) As mobilization as colloids is important especially right after the onset of reducing conditions but its importance decreases over time.

Metal ions are key components in atmosphere that potentially affect the optical properties and photochemical reactivity of atmospheric humic-like substances (HULIS), while this mechanism is still unclear. In this study, we demonstrated that atmospheric HULIS coupled with Fe

We assessed the diagnostic value of Sonazoid-enhanced ultrasound (SEUS) in determining the macroscopic classification of hepatocellular carcinoma (HCC) because of its strong relevance to the poor prognosis of the non-simple nodular (non-SN) type. The PubMed, EMBASE, Web of Science and Cochrane Library databases were searched for studies investigating patients who underwent surgery for HCC after undergoing SEUS pre-operatively. Five studies involving a total of 334 patients met the inclusion criteria. The summary sensitivity and specificity were 0.74 (95% confidence interval [CI]: 0.63-0.83) and 0.92 (95% CI: 0.82-0.97), respectively. The positive and negative likelihood ratios of SEUS for determining the macroscopic classification of HCC in Kupffer phase were 9.21 (95% CI: 4.02-21.13) and 0.28 (95% CI: 0.19-0.41), respectively. The diagnostic odds ratio of SEUS for determining the macroscopic classification of HCC was 34.2 (95% CI: 11.64-100.51), and the area under the summary receiver operating characteristic curve was 0.87 (95% CI: 0.84-0.90). Subgroup analysis suggested that small HCCs (≤30 mm) and studies including fewer than 70 patients may be associated with a higher diagnostic odds ratio than the corresponding subsets. SEUS had moderate diagnostic value for determining the macroscopic classification of HCC in the Kupffer phase.

Fe(III) heme is known to possess low catalytic activity when exposed to hydrogen peroxide and a reducing substrate. Efficient non-covalently linked Fe(III) heme-peptide complexes may represent suitable alternatives as a new group of green catalysts. Here, we evaluated a set of heme-peptide complexes by determination of their peroxidase-like activity and the kinetics of the catalytic conversion in both, the soluble and the immobilized state. We show the impact of peptide length on binding of the peptides to Fe(III) heme and the catalytic activity. Immobilization of the peptide onto a polymer support maintains the catalytic performance of the Fe(III) heme-peptide complex. This study thus opens up a new perspective with regard to the development of heterogeneous biocatalysts with a peroxidase-like activity.

Carbon monoxide (CO) is a bioactive molecule with high potential as it shows promising efficacy for regulating inflammation. Materials capable of storing and delivering CO are of great potential therapeutic value. Although CO-releasing molecules (CORMs) have been developed to deliver CO, the short CO duration of minutes to 2 h confines their practical use. In this study, partially reduced MIL-100(Fe) as a new CO-releasing nanoMOF was developed and used for sustained CO release and macrophage (MA) phenotypic polarization regulation. MIL-100(Fe) was synthesized and mildly annealed in vacuum for partial reduction. When the annealing temperature was lower than 250 °C, less Fe(II) present in MIL-100(Fe) and the subsequent CO adsorption and desorption profiles displayed typical features of physisorption. While it was annealed at 250 °C, it showed about 20% of Fe(III) was reduced, which resulted in chemisorption of CO due to the high coordination affinity of Fe(II) to CO. The loading amount of CO was increased, and the CO release was prolonged for about 24 h. Furthermore, the CO release from this nanoMOF could alter the lipopolysaccharide (LPS)-induced macrophage from M1 to the alternative M2 phenotype and promoted the growth of endothelial cells (ECs) by paracrine regulation of MA. It can be envisioned as a promising CO-releasing solid for biomedical application.

We report an electrochemical setup comprising a boron-doped diamond (BDD) working electrode for the electrochemical study of iron(III) catecholate siderophores. We demonstrate its successful application in the voltammetric investigation of iron(III) azotochelin, an iron complex of a bis(catecholate) siderophore. Cyclic voltammetry results, when complemented by UV-vis and native electrospray ionization-mass spectrometry (ESI-MS) characterization, reveal the formation of a coordinatively unsaturated tetracoordinate 1:1 complex of Fe:azotochelin (M

Microbially mediated iron redox processes are of great significance in the biogeochemical cycles of elements, which are often coupled with soil organic matter (SOM) in the environment. Although the influences of SOM fractions on individual reduction or oxidation processes have been studied extensively, a comprehensive understanding is still lacking. Here, using ferrihydrite

The in vitro antimicrobial activity of Fe(III) and Ga(III) complexes with N'-(2, 3-dihydroxy- phenylmethylidene)-3-pyr- idinecarbohydrazide (H 2 L 1), N'-(2, 4-dihydroxy-phenyl-methylidene)-3- pyridinecarbohydrazide (H 2 L 2), N'-(2, 5-dihy- droxy-phenylmethylidene)-3-pyridinecarbohydrazide (H 2 L 3), N'-(2-hydroxy-3-methoxyphenyl- methylidene)-3-pyri- dine-carbohydrazide (H 2 L 4), N'-(2-hydroxy-4-methoxyphenylmethyl-idene)-3- pyridine-carbohydrazide (H 2 L 5), and N'-(2- hydroxy-5-methoxyphenylmethylidene)-3- pyridinecarbo-hydrazide (H 2 L 6) toward several Gram-positive strains of Staphylococcus aureus, a Gram-negative strain of Escherichia coli, and a yeast Candida albicans were investigated. Fe(III)- complexes do not possess antimicrobial activity against all tested strains at concentrations up to 10 mg mL –1 . Ga(III) com- plexes with dihydroxy derivatives showed selective activity, while the broadest range of antibacterial and antifungal activities was observed for complex with 2- hydroxy-3-methoxy-derivative, ligand H 2 L 5. In addition, the coordination properties of ligands H 2 L 1 –H 2 L 3 in solution were investigated by UV–Vis spectroscopy. The stability constants (logK) for Ga(III)-H 2 L 1:1 complexes in MeOH/H 2 O 1/1 at pH 2.52 were determined, and amounted to 5.8, 5.68, and 4.7, respectively. Detailed characterization of complexes was performed by high-resolution mass spectrometry. The fragmentation pathways for dimer [Fe 2 (L 1) 2 ] 2+ , [Fe(HL) 2 ] + , [Ga(HL 2) 2 ] + and adduct ions are given. The comparison with analogue Ga(III) and Fe(III) com- plexes with compounds H 2 L 4 –H 2 L 6 was made as well.

Aquifer groundwater quality is largely controlled by sediment composition and physical heterogeneity, which commonly sustains a unique redox gradient pattern. Attenuation of heavy metals within these heterogeneous aquifers is reliant on multiple factors, including redox conditions and redox-active species that can further influence biogeochemical cycling. Here, we simulated an alluvial aquifer system using columns filled with natural coarse-grained sediments and two domains of fine-grained sediment lenses. Our goal was to examine heavy metal (Ni and Zn) attenuation within a complex aquifer network and further explore nitrate-rich groundwater conditions. The fine-grained sediment lenses sustained reducing conditions and served as a sink for Ni sequestration─in the form of Ni-silicates, Ni-organic matter, and a dominant Ni-sulfide phase. The silicate clay and sulfide pools were also important retention mechanisms for Zn; however, Ni was associated more extensively with organic matter compared to Zn, which formed layered double hydroxides. Nitrate-rich conditions promoted denitrification within the lenses that was coupled to the oxidation of Fe(II) and the concomitant precipitation of an Fe(III) phase with higher structural distortion. A decreased metal sulfide pool also resulted, where nitrate-rich conditions generated an average 20% decrease in solid-phase Ni, Zn, and Fe. Ultimately, nitrate plays a significant role in the aquifer's biogeochemical cycling and the capacity to retain heavy metals.

Bioleaching of metal sulfides is performed by diverse microorganisms. The dissolution of metal sulfides occurs via two chemical pathways, either the thiosulfate or the polysulfide pathway. These are determined by the metal sulfides’ mineralogy and their acid solubility. The microbial cell enables metal sulfide dissolution via oxidation of iron(II) ions and inorganic sulfur compounds. Thereby, the metal sulfide attacking agents iron(III) ions and protons are generated. Cells are active either in a planktonic state or attached to the mineral surface, forming biofilms. This review, as an update of the previous one (Vera et al., 2013a), summarizes some recent discoveries relevant to bioleaching microorganisms, contributing to a better understanding of their lifestyle. These comprise phylogeny, chemical pathways, surface science, biochemistry of iron and sulfur metabolism, anaerobic metabolism, cell–cell communication, molecular biology, and biofilm lifestyle. Recent advances from genetic engineering applied to bioleaching microorganisms will allow in the future to better understand important aspects of their physiology, as well as to open new possibilities for synthetic biology applications of leaching microbial consortia.Key points•Leaching of metal sulfides is strongly enhanced by microorganisms•Biofilm formation and extracellular polymer production influences bioleaching•Cell interactions in mixed bioleaching cultures are key for process optimization

Aims In AFFIRM-AHF, intravenous ferric carboxymaltose (FCM) reduced heart failure (HF) hospitalisations and improved quality of life versus placebo in iron-deficient patients stabilised after an acute HF episode. This analysis explored the effects of FCM versus placebo in patients with ischaemic and non-ischaemic HF aetiology. Methods and results We included 1082 patients from AFFIRM-AHF: 590 with ischaemic HF (defined as investigator-reported ischaemic HF aetiology and/or prior acute myocardial infarction and/or prior coronary revascularisation) and 492 with non-ischaemic HF. The prevalences of male sex, comorbidities, and history of HF were higher in the ischaemic versus non-ischaemic HF subgroup. Annualised event rates for the primary composite outcome of total HF hospitalisations and cardiovascular death with FCM versus placebo were 65.3 versus 100.6 per 100 patient-years in the ischaemic HF subgroup (rate ratio [RR] 0.65, 95% confidence interval [CI] 0.47-0.89, p = 0.007) and 58.3 versus 52.5 in the non-ischaemic HF subgroup (RR 1.11, 95% CI 0.75-1.66, p = 0.60) (p(interaction) = 0.039). An interaction between HF aetiology and treatment effect was also observed for the secondary outcome of total HF hospitalisations (p(interaction) = 0.038). A nominal increase in quality of life, assessed using the 12-item Kansas City Cardiomyopathy Questionnaire, was observed with FCM versus placebo, within each subgroup. Conclusions Heart failure hospitalisations and cardiovascular deaths occurred at a higher rate in patients with ishaemic versus those with non-ischaemic HF and were reduced by FCM versus placebo only in ischaemic patients. Further studies are needed to assess the role of aetiology in FCM efficacy.

Implant-associated infections (IAI) and osseointegration disorders are the most common complications in orthopedics. Studies have shown that neutrophils surrounding implants play a vital role in regulating these complications. Although magnesium (Mg) and its alloys are considered promising biodegradable bone implants, their role in neutrophil-mediated antibacteria has not yet been examined. Considering the rapid corrosion of Mg, it is necessary to develop methods to inhibit its corrosion. To solve these issues, a zinc-doped ferric oxyhydroxide nano-layer modified plasma electrolytic oxidation (PEO)-coated Mg alloy (PEO-FeZn) was developed in this study, and its antibacterial, immune anti-infective, and osteogenic ability were systematically evaluated. The results showed that PEO-FeZn nano-layer enhanced the corrosion resistance, biocompatibility, bactericidal activity, and osteoblastic differentiation activity of the Mg alloy. Moreover, PEO-FeZn nano-layer inhibited immune evasion-related gene expression and contributed to the formation of neutrophil extracellular traps (NETs) by activating the extracellular release of DNA fibers and granule proteins, and thereby suppressing bacterial invasion and promoting osseointegration in vivo in Staphylococcus aureus (S. aureus)-infected rat femurs. Overall, the findings of this study could serve as a reference for the fabrication of highly biocompatible and corrosion resistant Mg alloys to address the challenges of IAI and osseointegration disorders. STATEMENT OF SIGNIFICANCE: The widely used metallic biomaterials usually come with the risk of IAI. As the first responder around the biomaterials, neutrophils could form NETs to defense against microorganism and promote tissue remodeling. Therefore, biomaterials addressing antibacterial and neutrophils-modulatory strategies are highly necessary in reducing IAI. To solve these issues, we grew PEO-FeZn nano-layers in situ on Mg alloy using a simple and green technique. The nano-layer not only enhanced the corrosion resistance and biocompatibility of Mg alloy, but also elevated the antibacterial and osteogenesis capability. Moreover, nano-layer contributed to NETs formation, thereby suppressing bacterial invasion and even promoting osseointegration in S.aureus-infected femurs. Accordingly, this functionalized multilayer coating with antibacterial immunity represents a novel therapeutic strategy for IAI and weak osseointegration.

Phenoxyacetic acid herbicides (PAs) are widely used to control the growth of broad-leaf weeds in corn, tobacco, etc. The presence of PAs in plants even at low concentrations (at the ng/L to μg/L scale) may induce severe effects and lead to human health risks. Hence, a sensitive and reliable method for the determination of PAs at trace levels in cereals and vegetables is highly desired. Magnetic solid-phase extraction (MSPE) has attracted considerable attention on account of its benefits such as ease of separation, less solvent consumption, and good service life. In this study, aminated carbon nanotube-modified magnetic nanoparticles (NH

Vivianite is often found in reducing environments rich in iron and phosphorus from organic debris degradation or phosphorus mineral dissolution. The formation of vivianite is essential to the geochemical cycling of phosphorus and iron elements in natural environments. In this study, extracellular polymeric substances (EPS) were selected as the source of phosphorus. Microcosm experiments were conducted to test the evolution of mineralogy during the reduction of polyferric sulfate flocs (PFS) by Shewanella oneidensis MR-1 (S. oneidensis MR-1) at EPS concentrations of 0, 0.03, and 0.3 g/L. Vivianite was found to be the secondary mineral in EPS treatment when there was no phosphate in the media. The EPS DNA served as the phosphorus source and DNA-supplied phosphate could induce the formation of vivianite. EPS impedes PFS aggregation, contains redox proteins and stores electron shuttle, and thus greatly promotes the formation of minerals and enhances the reduction of Fe(III). At EPS concentration of 0, 0.03, and 0.3 g/L, the produced HCl-extractable Fe(II) was 107.9, 111.0, and 115.2 mg/L, respectively. However, when the microcosms remained unstirred, vivianite can be formed without the addition of EPS. In unstirred systems, the EPS secreted by S. oneidensis MR-1 could agglomerate at some areas, resulting in the formation of vivianite in the proximity of microbial cells. It was found that vivianite can be generated biogenetically by S. oneidensis MR-1 strain and EPS may play a key role in iron reduction and concentrating phosphorus in the oligotrophic ecosystems where quiescent conditions prevail.

Microparticles of iron oxide (MPIOs) are increasingly used for contrast generation in magnetic resonance imaging (MRI). In particular, Dynabeads® MyOne™ Tosylactivated MPIOs have enabled sensitive and targeted molecular imaging, e.g., to detect vascular inflammation. For the first time we measured the relaxivities as well as the molar susceptibility χ

In this work, we synthesized and characterized four titanium-porphyrin metal-organic frameworks (MOFs) [DGIST-1(M), M = Co(II), Fe(III), Zn(II), and H

Improving bioavailability of orally delivered drugs is still challenging, as conventional drug delivery systems suffer from non-specific drug delivery in the gastrointestinal (GI) tract and limited drug absorption efficiency. Gastric drug delivery is even more difficult due to the harsh microenvironment, short retention time, and physiologic barriers in the stomach. Here, an oral drug delivery microcapsule system was developed for gastric drug delivery, which consists of ionic liquid (IL) as the inner carrier and metal-phenolic network (MPN) as the microcapsule shell. The IL@MPN microcapsules are prepared by interfacial self-assembly of Fe

We report an iron-based graphite-conjugated electrocatalyst (GCC-FeDIM) that combines the well-defined nature of homogeneous molecular electrocatalysts with the robustness of a heterogeneous electrode. A suite of spectroscopic methods, supported by the results of DFT calculations, reveals that the electrode surface is functionalized by high spin (

The purpose of this study was to eliminate phosphate (P) from wastewater using MnFe2O4 nanoparticles. BET, TGA/DTG, FTIR, SEM, TEM, VSM, XRD and EDX/Map analyses were used to determine the MnFe2O4 surface properties. The specific surface area of the adsorbent was 196.56 m2/g and VSM analysis showed that the adsorbent has a ferromagnetic property. The maximum P sorption efficiency using MnFe2O4 (98.52%) was achieved at pH 6, temperature of 55 °C, P concentration of 10 mg/L, time of 60 min, and sorbent dosage of 2.5 g/L, which is a significant value. Also, the thermodynamic study indicated that the P sorption process is spontaneous and endothermic. Moreover, the utmost sorption capacity of P using MnFe2O4 was 39.48 mg/g. Besides, MnFe2O4 can be used for up to 6 reuse cycles with high sorption efficiency (>91%). Also, MnFe2O4 was able to remove phosphate, COD, and BOD5 from municipal wastewater with considerable removal efficiencies of 82.7%, 75.8%, and 77.3%, respectively.

Iron (Fe) minerals constitute a major control on organic carbon (OC) storage in soils and sediments. While previous research has mainly targeted Fe (oxyhydr)oxides, the impact of Fe sulfides and their subsequent oxidation on OC dynamics remains unresolved in redox-fluctuating environments. Here, we investigated the impact of dissolved organic matter (DOM) on FeS oxidation and how FeS and its oxidation may alter the retention and nature of DOM. After the anoxic reaction of DOM with FeS, FeS preferentially removed high-molecular-weight and nitrogen-rich compounds and promoted the formation of aqueous sulfurized organic molecules, according to Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS) analysis. When exposed to O

FeOOH as a naturally abundant, relatively low-cost and effective adsorbent have been gradually valued in wastewater field rich in arsenic pollution, which can make for environmental remediation. In this study, FeOOH samples included Gth1/Gth2 as goethite, Aka1/Aka2 as akaganéite, and Lep as lepidocrocite, were prepared and used as adsorbents, and adsorption kinetic and isotherm experiments of As(III) were analyzed. Meanwhile, the effects of pH, adsorbent content, arsenic initial concentration and electrolyte solutions on adsorption processes were also discussed in detail to study adsorption behaviors and mechanism. The results showed that As(III) could be effectively adsorbed on goethite, akaganéite and lepidocrocite, the adsorption equilibrium achieved after 24 h. When As(III) concentration ranged in 40 mg/L, the saturated adsorption amounts (mg/g) calculated by the Langmuir equation were 12.3 (Gth1), 7.50 (Gth2), 6.29 (Aka1), 23.4 (Aka2), and 17.7 (Lep). The increase of adsorbent and adsorbate levels was favorable to improve the adsorption capacities of As(III) within a certain range. Removal efficiency of As(III) with Na2SO4 and NaH2PO4 as electrolyte reduced by about 10% and 30%, respectively. Therefore, the appropriate parameters in the adsorption process for investigation were isomeric FeOOH of 1.0 g/L, pH 7.0 and NaNO3 as electrolyte. In simulated groundwater filter system initially with 200 μg/L of arsenic species at about pH 7.0, arsenic removal strength for five FeOOH adsorbents (0.8 g) was Aka2 > Aka1 and Gth1 > Lep and Gth2. Some differences were present in the infrared (IR) spectra of arsenic-loaded and original isomeric FeOOH. These outcomes could give the aim at seeking high efficient materials for the purification of arsenic contaminated groundwater and put out the suggestion.

The liver is one of the most frequent metastatic sites of breast cancer with a relatively poor prognosis. Systemic chemotherapy is an effective treatment but the efficacy is different between the subtypes of breast cancer. Percutaneous thermal ablation is considered to be a minimally invasive and effective local treatment for breast cancer liver metastases (BCLM). This case report described a patient with BCLM who adopted a strategy of systemic chemotherapy and repeated ultrasound (US) -guided percutaneous thermal ablation procedures. The survival time already reached 8 years till now with the metastases well-controlled and acceptable life quality was achieved.

Tumor metastasis and recurrence are recognized to be the main causes of failure in cancer treatment. To address these issues, an "all in one" and "one for all" nanoplatform was established for combined "chemo-immuno-photothermal" therapy with the expectation to improve the antitumor efficacy. Herein, Docetaxel (DTX, a chemo-agent) and cynomorium songaricum polysaccharide (CSP, an immunomodulator) were loaded into zein nanoparticles coated by a green tea polyphenols/iron coordination complex (GTP/Fe

Iron-containing drugs can be considered beneficial for noninvasive magnetic resonance imaging (MRI) and induction of essential biochemical processes. Herein, we present a new type of iron-containing drug based on molecular nanoparticles of ferric-tannic complexes (FTs), which could be used to enhance noninvasive brain MRI and modulate brain clearance pathways. Once intravenously administered to healthy Wistar rats, the maximum enhancement of the

Hemerythrin-like proteins (HLPs) are broadly distributed across taxonomic groups and appear to play highly diverse functional roles in prokaryotes. Mycobacterial HLPs contribute to the survival of these pathogenic bacteria in mammalian macrophages, but their modes of action remain unclear. A recent crystallographic characterization of

Fe(II)-catalyzed ferrihydrite transformation under anoxic conditions has been intensively studied, while such mechanisms are insufficient to be applied in oxic environments with depleted Fe(II). Here, we investigated expanded pathways of sunlight-driven ferrihydrite transformation in the presence of dissolved oxygen, without initial addition of dissolved Fe(II). We found that sunlight significantly facilitated the transformation of ferrihydrite to goethite compared to that under dark conditions. Redox active species (hole-electron pairs, reactive radicals, and Fe(II)) were produced from the ferrihydrite interface via the photoinduced electron transfer processes. Experiments with systematically varied wet chemistry conditions probed the relative contributions of three pathways for the production of hydroxyl radicals: (1) oxidation of water (5.0%); (2) reduction of dissolved oxygen (40.9%); and (3) photolysis of Fe(III)-hydroxyl complexes (54.1%). Results also showed superoxide radicals as the main oxidant for Fe(II) reoxidation under acidic conditions, thus promoting the ferrihydrite transformation. The presence of inorganic ions (chloride, sulfate, and nitrate) did not only affect the hydrolysis and precipitation of Fe(III) but also the generation of radicals via photoinduced charge transfer reactions. The involvement of redox active species and the accompanying mineral transformations would exert a profound effect on the fate of multivalent elements and organic contaminants in aquatic environments.

A highly efficient and atom-economic iron(III)-catalyzed three-component heteroannulation reaction between phenylpropiolamides, 3-formylchromones, and water is described for the construction of diversely multifunctionalized 2-pyridones. This protocol allows rapid access to a variety of 2-pyridones bearing an

Arsenic (As) is a toxic element, and elevated levels of geogenic As in drinking water pose a threat to the health of several hundred million people worldwide. In this study, we used microfluidics in combination with optical microscopy and X-ray spectroscopy to investigate zerovalent iron (ZVI) corrosion, secondary iron (Fe) phase formation, and As retention processes at the pore scale in ZVI-based water treatment filters. Two 250 μm thick microchannels filled with single ZVI and quartz grain layers were operated intermittently (12 h flow/12 h no-flow) with synthetic groundwater (pH 7.5; 570 μg/L As(III)) over 13 and 49 days. Initially, lepidocrocite (Lp) and carbonate green rust (GRC) were the dominant secondary Fe-phases and underwent cyclic transformation. During no-flow, lepidocrocite partially transformed into GRC and small fractions of magnetite, kinetically limited by Fe(II) diffusion or by decreasing corrosion rates. When flow resumed, GRC rapidly and nearly completely transformed back into lepidocrocite. Longer filter operation combined with a prolonged no-flow period accelerated magnetite formation. Phosphate adsorption onto Fe-phases allowed for downstream calcium carbonate precipitation and, consequently, accelerated anoxic ZVI corrosion. Arsenic was retained on Fe-coated quartz grains and in zones of cyclic Lp-GRC transformation. Our results suggest that intermittent filter operation leads to denser secondary Fe-solids and thereby ensures prolonged filter performance., Environmental Science & Technology, 56 (19), ISSN:0013-936X, ISSN:1520-5851

The presence of multiple oxidation and spin states of first-row transition-metal complexes facilitates the development of switchable MRI probes. Redox-responsive probes capitalize on a change in the magnetic properties of the different oxidation states of the paramagnetic metal ion center upon exposure to biological oxidants and reductants. Transition-metal complexes that are useful for MRI can be categorized according to whether they accelerate water proton relaxation (

Exploring sensors based on Förster resonance energy transfer (FRET) systems enables the continuous development of biological sensing technologies. Herein, we report the construction of a FRET sensor with dual-emissive quantum dots (QDs) and meso-tetra(4-sulfonatophenyl) porphine (TSPP). The sensor is composed of mesial green-emissive QDs with a thick silica shell (gQD@SiO

The preparation of biomass-derived carbon electrode materials with abundant active sites is suitable for development of energy-storage systems with high energy and power densities. Herein, a hybrid material consisting of highly-dispersed nickel ferrite nanoparticle on 3D hierarchical carboxymethyl cellulose-derived porous carbon (NiFe

Nanoscale, localized corrosion underpins billions of dollars in damage and material costs each year; however, the processes responsible have remained elusive due to the complexity of studying degradative material behavior at nanoscale liquid-solid interfaces. Recent improvements to liquid cell scanning/transmission electron microscopy and associated techniques enable this first look at the nanogalvanic corrosion processes underlying this widespread damage. Nanogalvanic corrosion is observed to initiate at the near-surface ferrite/cementite phase interfaces that typify carbon steel. In minutes, the corrosion front delves deeper into the material, claiming a thin layer of ferrite around all exposed phase boundaries before progressing laterally, converting the ferrite to corrosion product normal to each buried cementite grain. Over the following few minutes, the corrosion product that lines each cementite grain undergoes a volumetric expansion, creating a lateral wedging force that mechanically ejects the cementite grains from their grooves and leaves behind percolation channels into the steel substructure.

Although it is well-accepted that iron oxide nanoparticles are considered as artificial enzymes when their surface is hydrophilic, the enzyme-like properties of iron oxide nanoparticles with hydrophobic surface coating is unexplored. This work demonstrates that hydrophobic iron oxide nanocrystals coated with a layer of oleic acid could serve as artificial enzymes when their surface is covered by a layer of ionic surfactant. Furthermore, the co-assembly of iron oxide nanocrystals and porous organic cages could modulate their enzyme-like activities.Co-assembly of iron oxide (FeCo-assembly of Fe

The slow conversion of Fe(Ⅱ)/Fe(III) cycle was largely limited the degradation efficiency of many photo-Fenton systems. Herein, four Fe-MOFs nanorods (namely Fe-TCPP-1, Fe-TCPP-2, Fe-TCPP-3, Fe-TCPP-4) with decreasing length-diameter ratios were synthesized in a household microwave oven, using photosensitizer porphyrin and iron ions with Fenton activity as building blocks. Among them, the Fe-TCPP-3 exhibited high photogenerated electron-hole (e

Iron is the principal raw material for steel industries and Hematite is a principal ore of iron. Quantitative and qualitative estimation of iron in its ores is a crucial factor before its extraction. In this work, quantitative chemical analysis of iron was carried out from the collected seventy-two hematite samples from Pokhari, Nawalparasi. Sampling of the hematite ore was performed by channel sampling method. Chemical analysis was carried out by gravimetric, titrimetric, UV-Vis spectrophotometric and atomic absorption spectroscopic methods. The findings of different parameters in percentage areas follows: loss on ignition (1.76 ± 0.17), silica (47.06 ± 4.01), and iron (36.75 ± 2.50) by titrimetric analysis. Based on the chemical analysis, the Fe content in the collected hematite sample is in intermediate range. Thus, for the profitable iron extraction, other factors such as coverage of ores, extraction costs, and market value should be considered.

Both trans and cis iron–CTMC complexes, namely, trans-dichlorido[(5SR,7RS,12RS,14SR)-5,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradecane]iron(III) tetrachloridoferrate, [Fe(C14H32N4)Cl2][FeCl4] (1a), the analogous chloride methanol monosolvate, [Fe(C14H32N4)Cl2]Cl·CH3OH (1b), and cis-dichlorido[(5SR,7RS,12SR,14RS)-5,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradecane]iron(III) chloride, [Fe(C14H32N4)Cl2]Cl (2), were successfully synthesized and structurally characterized using X-ray diffraction. The coordination geometry of the macrocycle is dependent on the stereoisomerism of CTMC. The packing of these complexes appears to be strongly influenced by extensive hydrogen-bonding interactions, which are in turn determined by the nature of the counter-anions (1a versus 1b) and/or the coordination geometry of the macrocycle (1a/1b versus 2). These observations are extended to related ferric cis- and trans-dichloro macrocyclic complexes.

Ferric ions (Fe

Uranium mining and nuclear fuel production have led to significant U contamination. Past studies have focused on the bioreduction of soluble U(VI) to insoluble U(IV) as a remediation method. However, U(IV) is susceptible to reoxidation and remobilization when conditions change. Here, we demonstrate that a combination of adsorption and bioreduction of U(VI) in the presence of an organic ligand (siderophore desferrioxamine B, DFOB) and the Fe-rich clay mineral nontronite partially alleviated this problem. DFOB greatly facilitated U(VI) adsorption into the interlayer of nontronite as a stable U(VI)-DFOB complex. This complex was likely reduced by bioreduction intermediates such as the Fe(II)-DFOB complex and/or through electron transfer within a ternary Fe(II)-DFOB-U(VI) complex. Bioreduction with DFOB alone resulted in a mobile aqueous U(IV)-DFOB complex, but in the presence of both DFOB and nontronite U(IV) was sequestered into a solid. These results provide novel insights into the mechanisms of U(VI) bioreduction and the stability of U and have important implications for understanding U biogeochemistry in the environment and for developing a sustainable U remediation approach.

During the pyrite oxidation process, aqueous ferrous/ferric ions (Fe

A facultative anaerobic bacterium, designated as A25

Ovarian cancer has become an urgent threat to global female healthcare. Cisplatin, as the traditional chemotherapeutic agent against ovarian cancer, retains several limitations, such as drug resistance and dose-limiting toxicity. In order to solve the above problems and promote the therapeutic effect of chemotherapy, combining chemotherapy and phototherapy has aroused wide interest. In this study, we constructed a versatile cisplatin prodrug-conjugated therapeutic platform based on ultrasmall CuS-modified Fe(III)-metal-organic frameworks (MIL-88) (named M-Pt/PEG-CuS) for tumor-specific enhanced synergistic chemo-/phototherapy. After intravenous injection, M-Pt/PEG-CuS presented obvious accumulation in tumor and Fe(III)-MOFs possessed magnetic resonance imaging (MRI) to guide synergy therapy. Both in vitro and in vivo experimental results showed that M-Pt/PEG-CuS could not only successfully inhibit tumor growth by combining chemotherapy and NIR-II PTT but also avoid the generation of liver damage by the direct treatment of cisplatin(II). Our work presented the development of the nanoplatform as a novel NIR-II photothermal agent, as well as gave a unique combined chemo-photothermal therapy strategy, which might provide new ways of ovarian cancer therapy for clinical translation.

Since there are several limitations in cancer treatment for traditional chemotherapy, such as side effects, poor prognosis and drug resistance, developing new combined therapy is urgently needed. In this work, a biocompatible, simple and tumor microenvironment-responsive nanotheranostics (PCN-Oxpt/PEG) was built to favor the chemotherapy/ferroptosis/immunomodulation synergism in cancer. This nanotheranostics is constructed by modifying oxaliplatin prodrug and PEG on Fe(III) - porphyrin metal-organic frameworks (PCN(Fe) MOFs). After intravenous injection, the cloak of PEG leads to long circulation, and the Fe(III)-porphyrin MOFs enables dual-model guidance with fluorescence (FL) and magnetic resonance imaging (MRI). Inside the tumor, the intracellular H

In this work, the response surface methodology (RSM) was used to model and optimize the hydroxylamine (HA) enhanced Fe(II)/peroxymonosulfate (PMS) process. The enhanced effect of HA on the degradation efficiency of Orange II (AO7) in the Fe(II)/PMS system was quantitatively analyzed. Pareto analysis showed that the individual and interactive effects of HA, Fe(II) and PMS were of the following order: HA > Fe(II) > PMS and Fe(II)/PMS > HA/PMS > Fe(II)/HA. The optimal conditions of HA/Fe(II)/PMS system were as follows: Fe(II) concentration was 34.0 μM, HA concentration was 0.4 mM, and PMS concentration was 0.9 mM. When the initial pH was 4.0–6.0, the degradation efficiency of AO7 in the HA/Fe(II)/PMS system was significantly higher than that in the Fe(II)/PMS system (P < 0.05). Hydroxylamine enhances the degradation of AO7 in the Fe(II)/PMS system by reducing Fe(III) to Fe(II). The results of quenching experiment showed that SO4•− was the dominating reactive oxygen species (ROS) in the HA/Fe(II)/PMS system. In the HA/Fe(II)/PMS system, CO32− and humic acid inhibited the degradation efficiency of AO7. This work provides a novel mathematical model for the degradation of AO7 in the HA/Fe(II)/PMS system, which can be popularized and applied in similar experiments.

Mn(II) oxidation by free chlorine can be applied to remove Mn(II) at water treatment plants. This reaction also results in particulate MnO