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Featured Application: New sorbents based on polyacrylonitrile fiber and transition metal ferrocyanides can be used for 137Cs selective sorption from technological solutions (liquid low- and intermediate-level waste; seawater containing radioactive waste; wastewater), as well as from natural waters (fresh and saltwater) with the purpose of radioecological monitoring. For the first time, new sorbents based on polyacrylonitrile (PAN) fiber and transition metal ferrocyanides were obtained. The main difference between the obtained sorbents and the existing ones is the stage of preliminary preparation of the initial support by converting it into the forms PAN-Fe(OH)3 or PAN-MnO2, due to which additional ion exchange groups (carboxyl, carbonyl, etc.) are formed, which increases the amount of ferrocyanide fixed to the support. The best components and conditions for the synthesis of new sorbents were determined (concentration (0.1–0.2 mol/L), as well as pH (1 for sorbents based on PAN-Fe(OH)3, and 1–5—PAN-MnO2) of potassium ferrocyanide solution, concentration of transition metal salts (0.02 mol/L), temperature conditions). The influence of the studied solution composition (pH, concentration of Na+, K+, NH4+ ions) on the cesium distribution coefficients during its recovery by the obtained sorbents was assessed. The possibility of cesium recovery from solutions with pH 1–9 containing macro quantities of cations was demonstrated. The sorbents derived were characterized by modern structural methods such as infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy with EDS analysis. A study of the trace amount sorption of 137Cs was carried out in comparison with commercially available highly efficient sorbents (FNS-10 and Termoksid-35), and it was shown that the resulting sorbents are not inferior to industrial ferrocyanide sorbents and can be used for 137Cs selective sorption from technological solutions and natural waters. [ABSTRACT FROM AUTHOR]

Ferri and ferro coordination polymers in sphere structure were synthesized. Scanning Electron Microscopy (SEM) Energy Dispersive X-Ray Spectroscopy (EDX), Gel Permeation Chromatography (GPC), elemental analysis, and Fourier Transform Infrared Spectroscopy (FT-IR) were performed for chemical and structural characterization of the coordination polymers. Glucose oxidase (GOD) enzyme immobilized to compare of kinetic parameters deal with glucano-1,5 lacton formation. Analyses results illustrate that structures coordination of ions Fe2+ and Fe3+ are different to the same support. It was seen that 2 mol of Fe2+ ion ((PS-N-([Fe(CN)4L]K3)2) was bound per unit structure while 1 mol of Fe3+ ion (PS-N- ([Fe(CN)2L]K)) is attaching. Km values of were found as 15.32 and 10.93 for (PS-NFe2+)- GOD and (PS-N-Fe3+)-GOD, respectively. Km value for (PS-N-Fe3+)-GOD was found to be 0.5 times higher, possible reason of such a case is the larger reduction potential of Fe3+. As the charge on the coordination structure increased, the enzyme's affinity for the substrate increased. After 20 repeated measurements, GOD immobilized on (PS-N-Fe3+) polymer retained 45.47% activity, while GOD immobilized on (PS-N-Fe2+) polymer retained 57.86% activity. [ABSTRACT FROM AUTHOR]

The sorption properties of manganese (III, IV), the ferrocyanides sorbents to Na+ and K+ in Li salts water solutions have been studied. The sorption properties of the sorbents have been determined under batch and dynamic conditions using Li salts water solutions. The granulated sorbents, based on manganese oxide, obtained via interaction of KMnO4 and H2O2 solution, heated at 500°C, with NaOH or KOH, have the best characteristics. These sorbents are also chemically and mechanically stable for implementing them in the sorption-desorption procedure. The sorption resource of the granulated manganese oxide until the 50% breakthrough of sodium is 60 bed volumes, the potassium is 280 bed volumes. The investigated sorbents can be used in Na+ and K+ ions extraction for obtaining highly purified lithium salts. [ABSTRACT FROM AUTHOR]

Wearable devices for health monitoring and fitness management have foreseen a rapidly expanding market, especially those for noninvasive and continuous measurements with real-time display that provide practical convenience and eliminated safety/infection risks. Herein, a self-powered and fully integrated smartwatch that consists of flexible photovoltaic cells and rechargeable batteries in the forms of a "watch strap", electrochemical glucose sensors, customized circuits, and display units integrated into a "dial" platform is successfully fabricated for real-time and continuous monitoring of sweat glucose levels. The functionality of the smartwatch, including sweat glucose sensing, signal processing, and display, can be supported with the harvested/converted solar energy without external charging devices. The Zn-MnO2 batteries serve as intermediate energy storage units and the utilization of aqueous electrolytes eliminated safety concerns for batteries, which is critical for wearable devices. Such a wearable system in a smartwatch fashion realizes integration of energy modules with self-powered capability, electrochemical sensors for noninvasive glucose monitoring, and in situ and real-time signal processing/display in a single platform for the first time. The as-fabricated fully integrated and self-powered smartwatch also provides a promising protocol for statistical study and clinical investigation to reveal correlations between sweat compositions and human body dynamics.

Sodium-ion batteries (SIBs) are potential replacements for lithium-ion batteries owing to their comparable energy density and the abundance of sodium. However, the low potential and low stability of their cathode materials have prevented their commercialization. Prussian blue analogs are ideal cathode materials for SIBs owing to the numerous diffusion channels in their 3D structure and their high potential vs. Na/Na+. In this study, we fabricated various Fe-V-incorporated hexacyanoferrates, which are Prussian blue analogs, via a one-step synthesis. These compounds changed their colors from blue to green to yellow with increasing amounts of incorporated V ions. The X-ray photoelectron spectroscopy spectrum revealed that V3+ was oxidized to V4+ in the cubic Prussian blue structure, which enhanced the electrochemical stability and increased the voltage platform. The vanadium ferrocyanide Prussian blue (VFPB1) electrode, which contains V4+ and Fe2+ in the Prussian blue structure, showed Na insertion/extraction potential of 3.26/3.65 V vs. Na/Na+. The cycling test revealed a stable capacity of ~70 mAh g−1 at a rate of 50 mA g−1 and a capacity retention of 82.5% after 100 cycles. We believe that this Fe-V-incorporated Prussian green cathode material is a promising candidate for stable and high-voltage cathodes for SIBs. [ABSTRACT FROM AUTHOR]

Monitoring 137Cs in seawater is necessary for the timely detection of radioactive contamination. The possibility of sorption and the sorption efficiency of 137Cs from seawater were studied for the first time during several cruises of the R/V (research vessel) Professor Vodyanitsky using various types of sorbents based on transition metal ferrocyanides (Anfezh, Niket, Uniket, FSS, FD-M, FIC, Termoxid 35, NKF-C) and zirconium phosphate (Termoxid 3A). The influence of the seawater flow rate and volume of the sorbent used for the recovery of 137Cs was estimated. The ferrocyanide sorbents Niket, Uniket, Termoxid 35, and FIC showed the best sorption efficiency (60–100%) at a seawater flow rate of 2–4 column volumes per minute. The data obtained during three cruises on the R/V Professor Vodyanitsky were analyzed. A detailed (28 sampling points) spatial distribution of 137Cs in the Black Sea along the southern coast of Crimea was studied using the sorbents that showed the best characteristics. An increase in 137Cs activity in the study area was not found, and the average activity was 9.01 ± 0.87 Bq/m3. [ABSTRACT FROM AUTHOR]

Owing to their high redox potential and availability of numerous diffusion channels in metal–organic frameworks, Prussian blue analogs (PBAs) are attractive for metal ion storage applications. Recently, vanadium ferrocyanides (VFCN) have received a great deal of attention for application in sodium-ion batteries, as they demonstrate a stable capacity with high redox potential of ~3.3 V vs. Na/Na+. Nevertheless, there have been no reports on the application of VFCN in lithium-ion batteries (LIBs). In this work, a facile synthesis of VFCN was performed using a simple solvothermal method under ambient air conditions through the redox reaction of VCl3 with K3[Fe(CN)6]. VFCN exhibited a high redox potential of ~3.7 V vs. Li/Li+ and a reversible capacity of ~50 mAh g–1. The differential capacity plots revealed changes in the electrochemical properties of VFCN after 50 cycles, in which the low spin of Fe ions was partially converted to high spin. Ex situ X-ray diffraction measurements confirmed the unchanged VFCN structure during cycling. This demonstrated the high structural stability of VFCN. The low cost of precursors, simplicity of the process, high stability, and reversibility of VFCN suggest that it can be a candidate for large-scale production of cathode materials for LIBs. [ABSTRACT FROM AUTHOR]

The patterns of cesium recovery under static and dynamic conditions with new ferrocyanide sorbents based on pre-prepared polyacrylonitrile (PAN) fiber by converting the latter into PAN-MnO2 or PAN-Fe(OH)3 modifications were studied. Optimal sorption conditions for the obtained sorbents were determined. The dependence of cesium recovery degree on the sorption time was characterized using kinetic models of pseudo-first and pseudo-second order, the Elovich model, and also dependence of the sorbent capacity on the equilibrium concentration of cesium in solution using Langmuir and Freundlich isothermal models. It was found that sorption equilibrium is achieved in 8–20 h. Maximum capacity is achieved at the equilibrium concentration of cesium in the solution of more than 1500 mg L–1. The output sorption curves were constructed, based on which the dynamic (0.88–3.67 mg g) and total dynamic exchange capacities (15.5–26.9 mg g) of the obtained sorbents were determined. The desorption and kinetics of cesium desorption have been studied, and the best desorption agents and the optimal desorption time have been found out. During the marine expeditionary research, the high efficiency of 137Cs recovery (> 80%) from large volumes of seawater using the obtained sorbents was shown. [ABSTRACT FROM AUTHOR]

To understand how polyethyleneimine (PEI), as a ligand, affects structure and properties of the transition metals hexacyanoferrates (HCFs) immobilized in cross-linked PEI matrix, we have synthesized Cu(II), Zn(II), and Fe(III) HCFs via successive ion-exchange reactions with metal salts and K4[FeII(CN)6] or K3[FeIII(CN)6]. The structure and properties of the obtained materials in comparison with the crystalline HCF analogs were investigated with FT-IR, Mössbauer, and UV–Vis spectroscopy. Complete reduction of Fe(III) to Fe(II) by PEI in HCF(III) was confirmed. When synthesis was performed at pH favoring binding of precursor metal ions by PEI, cyano-bridged hybrids rather than polymer—HCFs composites were formed. Although the obtained hybrids did not demonstrate sorption activity toward cesium ions, known for crystalline HCFs, they are of interest for the other applications. SQUID measurements revealed a significant difference in magnetic properties of PEI–HCFs hybrids in comparison with crystalline HCFs. Due to the Fe(III) to Fe(II) reduction in HCF ions, Cu(II) and Fe(III) HCFs(III) lost the molecular magnets properties in PEI matrix, but magnetic ordering, including ferromagnet-antiferromagnet interactions, was observed in all hybrids over the broad temperature range. [ABSTRACT FROM AUTHOR]

A novel strategy is reported to access high-performance nanozymes via the self-coordination of ferrocyanides ([Fe(CN)6]4−) onto the surface of the Cu3BiS3 (CBS) nanorods. Notably, the in situ formed nanozymes had high catalytic activity, good stability, low cost, and easy mass production. The formed nanozyme catalyzed the oxidation of the typical chromogenic substrate of 3,3′,5,5′-tetramethylbenzidine (TMB) with a distinctive absorption peak at 652 nm, accompanied by a blue color development. Moreover, the attachment of deoxyribonucleoside 5′-monophosphates (dNMP) beforehand onto the surface of CBS prevented coordination of ferrocyanides and resulted in the tunable formation of the nanozyme, thereby enabling the construction of an exquisite biosensing platform. Taking the aptasensing of chloramphenicol (CAP) as an example, the engineered nanozyme allowed the construction of a homogenous, label-free, and high-performance bioassay in terms of its convenience and high sensitivity. Under the optimal conditions, changes in the absorption intensity at 652 nm for the oxidized TMB provides a good linear correlation with the logarithm of CAP concentrations in the range 0.1 pM to 100 nM, and the limit of detection was 0.033 pM (calculated from 3σ/s). Considering a vast number of bioreactions can be connected to dNMP production, we expect the engineerable nanozyme as a universal signal transduction scaffold for versatile applications in bioassays. Through the attachment of deoxyribonucleoside 5′-monophosphate (dNMP) on the surface of CBS to regulate the generation of self-coordinated nanozyme CBS/BiHCF, a homogeneous, label-free, and high-performance universal aptasensing platform was constructed. [ABSTRACT FROM AUTHOR]

Photothermal therapy (PTT) is an efficient way to combat bacterial infections and circumvent multidrug resistance. However, balancing efficacious bacterial killing and minimizing damage to the surrounding normal tissues remain a great challenge. Herein, a highly cooperative Prussian blue/kaolinite (PB/Kaol) hybrid nanosystem is constructed for antibacterial therapy to accelerate the healing of infected wounds. After hybridization with Kaol, the prepared PB/Kaol forms interfacial Al-O-Fe bonds, a fast charge transfer channel from Kaol to PB, which contributes to the enhanced photothermal effect of PB/Kaol. Additionally, the hydroxyl and Lewis acid-base sites of the Kaol surface could promote the adhesion of PB/Kaol to bacteria, thereby ensuring that as much hyperthermia as possible is focused on the bacteria and minimizing damage to the surrounding healthy tissues. Furthermore, PB/Kaol inherits the anti-inflammatory and hemostasis functions of PB and Kaol, resulting in the rapid healing of infected wounds.

The disappearance of the protective barrier after skin injury leads to the overproduction of reactive oxygen species (ROS) in response to various stimuli. Oxidative stress is one of the most important causes of delayed wound healing, leading to negative outcomes, such as excessive inflammatory response and impaired angiogenesis. In this study, we used microfluidic technology to integrate Prussian blue nanozymes and vascular endothelial growth factor and constructed multifunctional microspheres that improved local oxidative stress. In order to enhance the adhesion of the microspheres on the wound surface and prolong the release of the drug, we coated them with dopamine, ensuring uniform encapsulation on their surface. The microspheres adhered well to the wound surface and promoted wound healing by scavenging ROS, reducing the inflammatory response, and promoting angiogenesis. This strategy of integrating nanozymes and growth factors can have a synergistic effect, which is significant for wound healing., Competing Interests: Declaration of competing interest All authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Introduction: Thallium is a highly toxic metal, with most publications demonstrating poisoning from thallium salts. We report on a patient with elevated serum and urine thallium concentrations from an intentional ingestion of elemental thallium purchased from the internet for self-harm., Case Report: The regional poison center was contacted about an 18-year-old man who ingested a fragment from a 100-gram bar reported to be elemental thallium. Serial serum and urine thallium concentrations were obtained. Prussian blue was started on hospital day (HD) 2. A metal fragment was seen on abdominal x-ray and removed via colonoscopy on HD3. The ingested fragment was analyzed via inductively coupled plasma mass spectrometry (ICP-MS) and found to be 87.0% elemental thallium. The initial serum thallium concentration obtained on HD1 was 423.5 mcg/L (reference range < 5.1 mcg/L), which subsequently decreased to 4.5 mcg/L, 29 days after the ingestion. An initial random urine thallium concentration obtained on HD 3 was 1850.5 mcg/g creatinine (reference range < 0.4 mcg/g creatinine). The patient remained hospitalized for 23 days and, when seen in follow-up, had not developed any signs or symptoms of thallium toxicity., Discussion: Elemental thallium ingestion is a rare toxicologic exposure, with limited published clinical and analytical experience to guide management. This case report describes a patient with ingestion of elemental thallium who developed elevated serum and urine thallium concentrations and was treated with Prussian blue. Despite having elevated serum and urine thallium concentrations consistent with previous fatal exposures, more evidence is needed to understand the differences between elemental thallium and thallium salts., (© 2024. The Author(s).)

Myocardial infarction (MI) has a 5-year mortality rate of more than 50% due to the lack of effective treatments. Interactions between cardiomyocytes and the MI microenvironment (MIM) can determine the progression and fate of infarcted myocardial tissue. Here, a specially designed Melanin-based composite nanomedicines (MCN) is developed to effectively treat MI by reprogramming the MIM. MCN is a nanocomposite composed of polydopamine (P), Prussian blue (PB) and cerium oxide (Ce x O y ) with a Mayuan-like structure, which reprogramming the MIM by the efficient conversion of detrimental substances (H + , reactive oxygen species, and hypoxia) into beneficial status (O 2 and H 2 O). In coronary artery ligation and ischemia reperfusion models of male mice, intravenously injecting MCN specifically targets the damaged area, resulting in restoration of cardiac function. With its promising therapeutic effects, MCN constitutes a new agent for MI treatment and demonstrates potential for clinical application., (© 2024. The Author(s).)

We have investigated the electronic structures and optical properties of Fe, Co, and Ni ferrocyanide nanoparticles using first-principles relativistic many-electron calculations. The overall features of the theoretical absorption spectra for Fe, Ni, and Co ferrocyanides calculated using a first-principles many-electron method well reproduced the experimental one. The origins of the experimental absorption spectra were clarified by performing a configuration analysis based on the many-electron wave functions. For Fe ferrocyanide, the experimental absorption peaks originated from not only the charge-transfer transitions from Fe2+ to Fe3+ but also the 3d-3d intra-transitions of Fe3+ ions. In addition, the spin crossover transition of Fe3+ predicted by the many-electron calculations was about 0.24 eV. For Co ferrocyanide, the experimental absorption peaks were mainly attributed to the 3d-3d intra-transitions of Fe2+ ions. In contrast to the Fe and Co ferrocyanides, Ni ferrocyanide showed that the absorption peaks originated from the 3d-3d intra-transitions of Ni3+ ions in a low-energy region, while from both the 3d-3d intra-transitions of Fe2+ ions and the charge-transfer transitions from Fe2+ to Ni3+ in a high-energy region. These results were quite different from those of density-functional theory (DFT) calculations. The discrepancy between the results of DFT calculations and those of many-electron calculations suggested that the intra- and inter-atomic transitions of transition metal ions are significantly affected by the many-body effects of strongly correlated 3d electrons. [ABSTRACT FROM AUTHOR]

To understand how polyethyleneimine (PEI), as a ligand, affects structure and properties of the transition metals hexacyanoferrates (HCFs) immobilized in cross-linked PEI matrix, we have synthesized Cu(II), Zn(II), and Fe(III) HCFs via successive ion-exchange reactions with metal salts and K4[FeII(CN)6] or K3[FeIII(CN)6]. The structure and properties of the obtained materials in comparison with the crystalline HCF analogs were investigated with FT-IR, Mössbauer, and UV–Vis spectroscopy. Complete reduction of Fe(III) to Fe(II) by PEI in HCF(III) was confirmed. When synthesis was performed at pH favoring binding of precursor metal ions by PEI, cyano-bridged hybrids rather than polymer—HCFs composites were formed. Although the obtained hybrids did not demonstrate sorption activity toward cesium ions, known for crystalline HCFs, they are of interest for the other applications. SQUID measurements revealed a significant difference in magnetic properties of PEI–HCFs hybrids in comparison with crystalline HCFs. Due to the Fe(III) to Fe(II) reduction in HCF ions, Cu(II) and Fe(III) HCFs(III) lost the molecular magnets properties in PEI matrix, but magnetic ordering, including ferromagnet-antiferromagnet interactions, was observed in all hybrids over the broad temperature range.

In this paper, novel composite materials from modified roasted date pits using ferrocyanides were developed and investigated for the recovery of lithium ions (Li+) from seawater reverse osmosis (RO) brine. Two composite materials were prepared from roasted date pits (RDP) as supporting material, namely potassium copper hexacyanoferrate-date pits composite (RDP-FC-Cu), and potassium nickel hexacyanoferrate-date pits composite (RDP-FC-Ni). The physiochemical characterization of the RO brine revealed that it contained a variety of metals and salts such as strontium, zinc, lithium, and sodium chlorides. RDP-FC-Cu and RDP-FC-Ni exhibited enhanced chemical and physical characteristics than RDP. The optimum pH, which attained the highest adsorption removal (%) for all adsorbents, was at pH 6. In addition, the highest adsorption capacities for the adsorbents were observed at the initial lithium concentration of 100 mg/L. The BET surface area analysis confirmed the increase in the total surface area of the prepared composites from 2.518 m2/g for RDP to 4.758 m2/g for RDP-FC-Cu and 5.262 m2/g for RDP-FC-Ni. A strong sharp infrared peak appeared for the RDP-FC-Cu and RDP-FC-Ni at 2078 cm−1. This peak corresponds to the C≡N bond, which indicates the presence of potassium hexacyanoferrate, K4[Fe(CN)6]. The adsorption removal of lithium at a variety of pH ranges was the highest for RDP-FC-Cu followed by RDP-FC-Ni and RDP. The continuous increase in the adsorption capacity for lithium with increasing initial lithium concentrations was also observed. This could be mainly attributed to enhance and increased lithium mass transfer onto the available adsorption active sites on the adsorbents' surface. The differences in the adsorption in terms of percent adsorption removal were clear and significant between the three adsorbents (P value < 0.05). All adsorbents in the study showed a high lithium desorption percentage as high as 99%. Both composites achieved full recoveries of lithium from the RO brine sample despite the presence of various other competing ions. [ABSTRACT FROM AUTHOR]

Cerebral microbleeds are microscopic hemorrhages with deposits of blood products in the brain, which can be visualized with MRI and are implicated in cerebrovascular diseases. Hematoxylin and eosin (H&E) and Perl's Prussian blue are popular staining methods used to localize cerebral microbleeds in pathology. This paper compared these two staining techniques in a mouse model of cerebral microbleeds. We used lipopolysaccharide (LPS) to induce cerebral microhemorrhages. C57B6 mice were treated with LPS (5 mg/kg, i.p.) or vehicle at baseline and at 24 hr. The brains were extracted 48 hr after the first injection and adjacent coronal sections were stained with H&E and Prussian blue to compare the effectiveness of the two staining techniques. H&E-positive stains were increased with LPS treatment and were correlated with grossly visible microhemorrhages on the brain surface; Prussian blue-positive stains, by comparison, showed no significant increase with LPS treatment and did not correlate with either H&E-positive stains or surface microhemorrhages. H&E staining is thus a more reliable indicator of acute bleeding events induced by LPS in this model within a short time span.

Humans with ALS and transgenic rodents expressing ALS-associated superoxide dismutase (SOD1) mutations develop spontaneous blood-spinal cord barrier (BSCB) breakdown, causing microvascular spinal-cord lesions. The role of BSCB breakdown in ALS disease pathogenesis in humans and mice remains, however, unclear, although chronic blood-brain barrier opening has been shown to facilitate accumulation of toxic blood-derived products in the central nervous system, resulting in secondary neurodegenerative changes. By repairing the BSCB and/or removing the BSCB-derived injurious stimuli, we now identify that accumulation of blood-derived neurotoxic hemoglobin and iron in the spinal cord leads to early motor-neuron degeneration in SOD1(G93A) mice at least in part through iron-dependent oxidant stress. Using spontaneous or warfarin-accelerated microvascular lesions, motor-neuron dysfunction and injury were found to be proportional to the degree of BSCB disruption at early disease stages in SOD1(G93A) mice. Early treatment with an activated protein C analog restored BSCB integrity that developed from spontaneous or warfarin-accelerated microvascular lesions in SOD1(G93A) mice and eliminated neurotoxic hemoglobin and iron deposits. Restoration of BSCB integrity delayed onset of motor-neuron impairment and degeneration. Early chelation of blood-derived iron and antioxidant treatment mitigated early motor-neuronal injury. Our data suggest that BSCB breakdown contributes to early motor-neuron degeneration in ALS mice and that restoring BSCB integrity during an early disease phase retards the disease process.

The article deals with the study of sorption (under batch conditions) of cesium and strontium radionuclides from sea water with ferrocyanidic sorbents based on hydrated titanium and zirconium dioxides (Т-35, NPF-HTD), glauconite and clinoptilolite natural aluminum silicates (NPF-G, NPF-C), zirconium phosphate (Т-3А), modified hydrated zirconium dioxide (Т-3К), and manganese dioxide based on hydrated titanium dioxide (MD-HTD). We have obtained the sorption isotherms, defined the cesium and strontium distribution coefficients. Dependences of the cesium distribution coefficient by the sorbents in seawater saline content have been obtained. The authors recommend NPF-G and NPF-HTD sorbents for treatment of liquid radioactive waste based on seawater with various salt content. Coefficients of the cesium distribution between solid and liquid phases were 1,0∙105 and 1,0∙104 mg/l, respectively, even at solutions with the salt content of 100 g/l. In the process of strontium sorption from seawater, the strontium distribution coefficients do not exceed 1,9·102 ml/g, this is connected with big proportion (34±7 %) of stable colloidal forms of strontium in the simulated seawater.

We present an advanced multimodality characterization platform for simultaneous optical and electrochemical measurements of ferrocyanides. Specifically, we combined a fiber-optic Fabry–Perot interferometer with a three-electrode electrochemical setup to demonstrate a proof-of-principle of this hybrid characterization approach, and obtained feasibility data in its monitoring of electrochemical reactions in a boron-doped diamond film deposited on a silica substrate. The film plays the dual role of being the working electrode in the electrochemical reaction, as well as affording the reflectivity to enable the optical interferometry measurements. Optical responses during the redox reactions of the electrochemical process are presented. This work proves that simultaneous opto-electrochemical measurements of liquids are possible. [ABSTRACT FROM AUTHOR]

Deep eutectic solvent (DES) was applied to the solvent of thermocell and high Seebeck coefficient (Se) of the thermocell was achieved at high-temperatures operation. The Se of a redox couple of ferricyanide and ferrocyanide ([Fe(CN)6]3−/4−) reaches − 1.67 mV/K in a DES consisting of ethylene glycol and choline chloride. Spectroscopic analysis reveals that this is due to the strong interactions between the redox couple and the DES. Furthermore, the cell can operate over a wide temperature range of 135–165 °C. This result is a desired feature for waste-heat recovery applications. [ABSTRACT FROM AUTHOR]

Cobalt Prussian blue analogues (Co-PBA; NaxCo[Fe(CN)6]y), consisting of cyano-bridged transition metal network, –Fe–CN–Co–NC–Fe–, are promising cathode materials for Na-ion secondary batteries. In the oxidation process, oxidization of Fe and/or Co are compensated by Na+ deintercalation. Here, we investigated the oxidization process of three Co-PBAs by means of in situ infrared absorption (IR) spectroscopy. With use of an empirical rule of the frequencies of the CN− stretching mode in ferrocyanide ([FeII(CN)6]4−) and ferricyanide ([FeIII(CN)6]3−), the oxidation processes of Co-PBAs were determined against the Fe concentration (y) and temperature (T). We will discuss the interrelation between the oxidation processes and Fe concentration (y). [ABSTRACT FROM AUTHOR]

The kinetics of cesium and strontium sorption by natural clinoptilolite and its ferrocyanide-modified analogs, NPF-Cl and NPF-Cl (Ca-form), from solutions of various compositions containing 100 mg L–1 sorbate was studied, and the texture and porosity of the sorbent samples before and after the sorption of cesium and strontium were determined. The sorption process occurs in three-stages and is limited by a heterogeneous ion exchange reaction (HIOR) on the ferrocyanide phase located on the outer surface of clinoptilolite and in its macropores, internal diffusion of cesium and strontium into sorbent granule, and precipitation of ferrocyanide phases of complex composition in small mesopores and micropores of sorbents. The HIOR and precipitation occur with involvement of solution components (sodium, calcium, and iron). Sorption of cesium and strontium is accompanied by a significant change in the texture and porosity of the sorbents. [ABSTRACT FROM AUTHOR]

Prussian blue analogues (PBAs) are promising materials due to their rich active sites and straightforward synthesis. However, their limited conductivity and electron transfer inefficiency hinder practical applications. This study utilizes a simple one-pot synthesis approach to produce a tungsten-disulfide (WS 2 ) and iron-cobalt Prussian blue analogue composite (WS 2 -PBA), enhancing conductivity and electron transfer rate performance. Through the inclusion of sodium citrate into the solution, the S-edge site concentration of WS 2 increases. This augmentation introduces additional active sites and defects into the catalyst, enhancing its catalytic activity. The effectiveness of the WS 2 -PBA 3D-Origami paper device for lactate detection in sweat is also evaluated for biomedical applications. The device demonstrated a robust relationship between the lactate concentration and current intensity (R 2  = 0.997), with a detection limit of 1.83 mM. Additionally, this platform has successfully detected lactate in clinical sweat, correlating with the high-performance liquid chromatography test results, suggesting promising prospects for clinical diagnosis. In the future, the excellent catalytic and R ct performance of the WS 2 -PBA will enable its use in biomedical applications., 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.)

Cell membrane-camouflaged nanoparticles possess inherent advantages derived from their membrane structure and surface antigens, including prolonged circulation in the bloodstream, specific cell recognition and targeting capabilities, and potential for immunotherapy. Herein, we introduce a cell membrane biomimetic nanodrug platform termed MPB-3BP@CM NPs. Comprising microporous Prussian blue nanoparticles (MPB NPs) serving as both a photothermal sensitizer and carrier for 3-bromopyruvate (3BP), these nanoparticles are cloaked in a genetically programmable cell membrane displaying variants of signal regulatory protein α (SIRPα) with enhanced affinity to CD47. As a result, MPB-3BP@CM NPs inherit the characteristics of the original cell membrane, exhibiting an extended circulation time in the bloodstream and effectively targeting CD47 on the cytomembrane of colorectal cancer (CRC) cells. Notably, blocking CD47 with MPB-3BP@CM NPs enhances the phagocytosis of CRC cells by macrophages. Additionally, 3BP, an inhibitor of hexokinase II (HK 2 ), suppresses glycolysis, leading to a reduction in adenosine triphosphate (ATP) levels and lactate production. Besides, it promotes the polarization of tumor-associated macrophages (TAMs) towards an anti-tumor M1 phenotype. Furthermore, integration with MPB NPs-mediated photothermal therapy (PTT) enhances the therapeutic efficacy against tumors. These advantages make MPB-3BP@CM NPs an attractive platform for the future development of innovative therapeutic approaches for CRC. Concurrently, it introduces a universal approach for engineering disease-tailored cell membranes for tumor therapy., (© 2024. The Author(s).)

Synovial macrophages play an important role in the progression of osteoarthritis (OA). In this study, we noted that synovial macrophages can activate pyroptosis in a gasdermin d-dependent manner and produce reactive oxygen species (ROS), aberrantly activating the mammalian target of rapamycin complex 1 (mTORC1) pathway and matrix metalloproteinase-9 (MMP9) expression in synovial tissue samples collected from both patients with OA and collagen-induced osteoarthritis (CIOA) mouse model. To overcome this, we constructed rapamycin- (RAPA, a mTORC1 inhibitor) loaded mesoporous Prussian blue nanoparticles (MPB NPs, for catalyzing ROS) and modified the NPs with MMP9-targeted peptides (favor macrophage targeting) to develop RAPA@MPB-MMP9 NPs. The inherent enzyme-like activity and RAPA released from RAPA@MPB-MMP9 NPs synergistically impeded the pyroptosis of macrophages and the activation of the mTORC1 pathway. In particular, the NPs decreased pyroptosis-mediated ROS generation, thereby inhibiting cGAS-STING signaling pathway activation caused by the release of mitochondrial DNA. Moreover, the NPs promoted macrophage mitophagy to restore mitochondrial stability, alleviate pyroptosis-related inflammatory responses, and decrease senescent synoviocytes. After the as-prepared NPs were intra-articularly injected into the CIOA mouse model, they efficiently attenuated synovial macrophage pyroptosis and cartilage degradation. In conclusion, our study findings provide a novel therapeutic strategy for OA that modulates the pyroptosis and mitophagy of synovial macrophage by utilizing functionalized NPs. STATEMENT OF SIGNIFICANCE: Osteoarthritis (OA) presents a significant global challenge owing to its complex pathogenesis and finite treatment options. Synovial macrophages have emerged as key players in the progression of OA, managing inflammation and tissue destruction. In this study, we discovered a novel therapeutic strategy in which the pyroptosis and mitophagy of synovial macrophages are targeted to mitigate OA pathology. For this, we designed and prepared rapamycin-loaded mesoporous Prussian blue nanoparticles (RAPA@MPB-MMP9 NPs) to specifically target synovial macrophages and modulate their inflammatory responses. These NPs could efficiently suppress macrophage pyroptosis, diminish reactive oxygen species production, and promote mitophagy, thereby alleviating inflammation and protecting cartilage integrity. Our study findings not only clarify the intricate mechanisms underlying OA pathogenesis but also present a promising therapeutic approach for effectively managing OA by targeting dysregulation in synovial macrophages., 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 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Prussian blue analogues, as prospective electrode materials, play a crucial role in detecting heavy metal ions (HMIs), a process closely related to their electron transfer capacities and active surfaces. Here, etched copper-iron Prussian blue analogues (CuFe-PBA) are synthesized through a combination of flash nanoprecipitation (FNP) and an alkali etching process. Furthermore, this study investigates the impact of ammonia on the electronic structure of CuFe-PBA and its electrochemical detection capabilities for HMIs. The etched CuFe-PBA (e-CuFe-PBA) exhibits excellent detection performance for Cd 2+ , Pb 2+ and Hg 2+ with 17.6 μA μM -1 , 24.2 μA μM -1 and 26.2 μA μM -1 , respectively, due to the fact that the ammonia etching not only modulates the electronic properties of the surface of CuFe-PBA but also reduces the degree of agglomeration and enhances the accessible surface area. Additionally, it demonstrates excellent stability and resistance to interference, having been successfully applied to detect HMIs in food samples such as preserved eggs and apple juice. These results provide a new strategy for the use of Prussian blue analogues as electrochemical sensors for food safety applications., 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.)

Hexanal is considered as an important volatile compound indicator for the assessment of freshness and maturity of foods. Therefore, sensitive and stable monitoring of hexanal is highly desired. Herein, an efficient receptor immobilization strategy based on ZIF-8@ Single-walled carbon nanotube (SWCNT) and nanosomes-AuNPs/Prussian blue (PB) was proposed for the development of olfactory biosensors. ZIF-8@SWCNT as dual support materials provided a high density of active sites for nanosomes loading. Moreover, the co-electrodeposition of nanosomes-AuNPs and PB on the sensor interface effectively amplified the electrochemical signal and maintained the activity of the receptor. The combination of ZIF-8@SWCNT with AuNPs/PB imparts excellent sensing performance of the biosensor with a wide detection range of 10 -16 -10 -9  M, a low detection limit of 10 -16  M for hexanal, and a long storage stability of 15 days. These results indicate that our biosensor can be a powerful tool for versatile applications in food and other related industries., 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 Ltd. All rights reserved.)

An electrochemical aptasensor was developed for the determination of chloramphenicol (CAP) in fresh foods and food products. The aptasensor was developed using Prussian blue (PB) and chitosan (CS) film. PB acts as a redox probe for detection and CS acts as a sorption material. The aptamer (Apt) was immobilized on a screen-printed carbon electrode (SPCE) modified with gold nanoparticles (AuNPs). Under optimum conditions, the linearity of the aptasensor was between 1.0 and 6.0 × 10 6  ng L -1 with a detection limit of 0.65 and a quantification limit of 2.15 ng L -1 . The electrode could be regenerated up to 24 times without the use of chemicals. The aptasensor showed good repeatability (RSD <11.2%) and good reproducibility (RSD <7.7%). The proposed method successfully quantified CAP in milk, shrimp pond water and shrimp meat with good accuracy (recovery = 88.0 ± 0.6% to 100 ± 2%). The proposed aptasensor could be especially useful in agriculture to ensure the quality of food and the environment and could be used to determine other antibiotics., 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.)

Objectives: A novel clinically translatable iron oxide nanoparticle (IOP) is currently being tested in phase 2 clinical trials as a magnetic resonance imaging (MRI) contrast agent for hepatocellular carcinoma diagnosis. The purpose of our study is to evaluate if this IOP can detect activation of tumor-associated macrophages (TAMs) due to CD47 mAb-targeted immunotherapy in 2 mouse models of osteosarcoma., Materials and Methods: The toxicity, biodistribution, and pharmacokinetics of IOP were evaluated in 77 female and 77 male rats. Then, 24 female BALB/c mice with intratibial murine K7M2 tumors and 24 female NOD scid gamma mice with intratibial human 143B osteosarcoma xenografts were treated with either CD47 mAb (n = 12) or control antibody (n = 12). In each treatment group, 6 mice underwent MRI scans before and after intravenous infusion of either IOP or ferumoxytol (30 mg Fe/kg). Tumor T2* values and TAM markers F4/80, CD80, CD206, and Prussian blue staining were compared between different experimental groups using exact 2-sided Wilcoxon rank sum tests., Results: Biodistribution and safety evaluations of IOP were favorable for doses of less than 50 mg Fe/kg body weight in female and male rats. Both IOP and ferumoxytol caused negative enhancement (darkening) of the tumor tissue. Both murine and human osteosarcoma tumors treated with CD47 mAb demonstrated significantly shortened T2* relaxation times after infusion of IOP or ferumoxytol compared with controls (all P 's < 0.05). Higher levels of F4/80 + CD80 + were found in murine and human osteosarcomas treated with CD47 mAb compared with sham-treated controls (all P 's < 0.05). In addition, murine CD47 mAb-treated tumors after infusion of either IOP or ferumoxytol showed significantly higher numbers of Prussian blue-positive cells compared with controls ( P < 0.05). There was no significant difference of F4/80 + CD206 + cells among any of the groups (all P 's > 0.05)., Conclusions: Iron oxide nanoparticle-enhanced MRI can be used to diagnose CD47 mAb-mediated TAM-activation in osteosarcomas., Competing Interests: Conflicts of interest: none declared., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Mitochondrial injury, neuronal apoptosis and phenotypic transformation of macrophages are the main mechanisms of spinal cord injury. Based on the Prussian blue nanomase's strong ability to clear free radicals, the treatment of spinal cord injury with nano-zirconium (Pb-Zr) was carried out. The disease treatment strategy based on nanomaterials has excellent therapeutic effect, and Prussian blue analogs have good therapeutic properties, so the application prospects of Prussian blue analogs is broad. From the point of view of Prussian blue content, improving the presence of zirconium in the microenvironment significantly increased the activity of Prussian blue. Prussian Blue zirconium significantly improved lipopolysaccharide (LPS) and interferon (IFN-γ) induced neuronal cell (pc12 cells) and macrophage dysfunction by improving oxidative stress, inflammation, and apoptosis in the microenvironment. It can promote the recovery of motor function after spinal cord injury. In vivo experiments, it shows that Prussian blue zirconium can improve inflammation, apoptosis and oxidative stress of spinal cord tissue, promote regenerative therapy after spinal cord injury, and improve motor function. Moreover, it has been reported that high-priced Zr 4+ cations can regulate the deposition and nucleation behavior of Zn 2+ in high-performance zinc metal anodes. Therefore, we propose the hypothesis that Pb-Zr modulates Zn 2+ be used to promote recovery from spinal cord injury. The results show that nanomaterial is beneficial in the treatment of spinal cord injury. This study provides a good prospect for the application of spinal cord injury treatment. It also provides an important feasibility for subsequent clinical conversions., 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.)

Backgrounds: Joint iron overload in hemochromatosis induces M1 polarization in synovial macrophages, releasing pro-inflammatory factors and leading to osteoarthritis development. However, the mechanism by which iron overload regulates M1 polarization remains unclear. This study aims to elucidate the mechanism by which synovial iron overload promotes macrophage M1 polarization., Methods: In vitro, RAW264.7 macrophages were treated with iron and divided into five groups based on the concentration of the iron chelator, desferrioxamine (DFO): Ctrl, Fe, DFO1, DFO2, and DFO3. In vivo, rats were categorized into five groups based on iron overload and intra-articular DFO injection: A-Ctrl, A-Fe, A-DFO1, A-DFO2, and A-DFO3. Osteoarthritis was induced by transecting the left knee anterior cruciate ligament. Macrophage morphology was observed; Prussian Blue staining quantified iron deposition in macrophages, synovium, and liver; serum iron concentration was measured using the ferrozine method; cartilage damage was assessed using H&E and Safranin O-Fast Green staining; qPCR detected iNOS and Arg-1 expression; Western Blot analyzed the protein expression of iNOS, Arg-1, 4E-BP1, phosphorylated 4E-BP1, p70S6K, and phosphorylated p70S6K; ELISA measured TNF-α and IL-6 concentrations in supernatants; and immunohistochemistry examined the protein expression of F4/80, iNOS, Arg-1, 4E-BP1, phosphorylated 4E-BP1, p70S6K, and phosphorylated p70S6K in the synovium., Results: In vitro, iron-treated macrophages exhibited Prussian Blue staining indicative of iron overload and morphological changes towards M1 polarization. qPCR and Western Blot revealed increased expression of the M1 polarization markers iNOS and its protein. ELISA showed elevated TNF-α and IL-6 levels in supernatants. In vivo, ferrozine assay indicated significantly increased serum iron concentrations in all groups except A-Ctrl; Prussian Blue staining showed increased liver iron deposition in all groups except A-Ctrl. Iron deposition in rat synovium decreased in a DFO concentration-dependent manner; immunohistochemistry showed a corresponding decrease in iNOS and phosphorylated 4E-BP1 expression, and an increase in Arg-1 expression., Conclusion: Intracellular iron overload may exacerbate joint cartilage damage by promoting synovial macrophage M1 polarization through phosphorylation of 4E-BP1 in the mTORC1-p70S6K/4E-BP1 pathway., 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 The Authors. Published by Elsevier B.V. All rights reserved.)

Sepsis is a life-threatening condition involving dysfunctional organ responses stemming from dysregulated host immune reactions to various infections. The lungs are most prone to failure during sepsis, resulting in acute lung injury (ALI). ALI is associated with oxidative stress and inflammation, and current therapeutic strategies are limited. To develop a more specific treatment, this study aimed to synthesise Prussian blue nanozyme (PBzyme), which can reduce oxidative stress and inflammation, to alleviate ALI. PBzyme with good biosafety was synthesised using a modified hydrothermal method. PBzyme was revealed to be an activator of haem oxygenase-1 (HO-1), improving survival rate and ameliorating lung injury in mice. Zinc protoporphyrin, an inhibitor of HO-1, inhibited the prophylactic therapeutic efficacy of PBzyme on ALI, and affected the nuclear factor-κB signaling pathway and activity of HO-1. This study demonstrates that PBzyme can alleviate oxidative stress and inflammation through HO-1 and has a prophylactic therapeutic effect on ALI. This provides a new strategy and direction for the clinical treatment of sepsis-induced ALI., Competing Interests: Declaration of competing interest All authors disclosed no relevant relationships., (Copyright © 2024. Published by Elsevier B.V.)

Prussian blue nanozymes (PBNs) with multiple enzyme activities are prepared and their activities of antitumor in nasopharyngeal carcinoma cells (CEN2) are also explored in this research. On the one hand, it shows that PBNs can exert the catalase-like (CAT-like) activity to decompose hydrogen peroxide (H 2 O 2 ) into non-toxic H 2 O in CEN2 cells. The O 2 release of H 2 O 2 catalysed by PBNs effectively alleviates the hypoxic environment of tumors, which inhibits the glycolysis of tumor and reduces the production of lactic acid. On the other hand, we also find that PBNs also has peroxidase-like (POD-like) enzymatic activity, which can catalyze the production of·OH from H 2 O 2 in tumor cells and result in tumor cell apoptosis. This study lays a solid biomedical foundation for the development of safe and non-toxic nanozymes, as well as the expansion of their application in tumor treatment., Competing Interests: Declaration of Compting Interest The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The rational development of efficient nanozymes for the colorimetric detection of targets is still challenging. Herein, Prussian blue analogues of Ni-Co-MoS 2 nano boxes were fabricated for colorimetric detection of glyphosate and copper ions owing to its peroxidase like activity. At the sensing system, the Ni-Co-MoS 2 nano boxes display high peroxidase activity, which could catalytically oxidize the colourless TMB to blue colour oxTMB. In presence of glyphosate in this sensing system the blue colour is diminished, ascribed to the inhibit the catalytic activity of Ni-Co-MoS 2 nano boxes. Concurrently, the addition of copper ion, which result in blue colour was reappear due to the generation of glyphosate-copper complex formation. The Ni-Co-MoS 2 nano boxes based colorimetric sensing platform was developed to sensitive detection of glyphosate and copper ions with low detection limit of 3 nM for glyphosate and 3.8 nM for copper. This method also displays satisfactory outcomes from real samples analysis and its good accuracy. Therefore, this work provides a great potential for rapid detection of the targets from the environments., 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.)

Chronic wound infections, particularly multidrug-resistant microbe-caused infections, have imposed severe challenges in clinical administration. The therapeutic effectiveness of the current strategy using conventional antibiotics is extremely unsatisfactory. The development of novel treatment strategies to inhibit the infections caused by multidrug-resistant bacteria is highly desired. In this work, based on the combination of nanocompounds with the assistance of NIR laser, an antibacterial strategy was designed for MRSA-infected abscesses in diabetic mice. The nanocompounds named Ag@Chi-PB were prepared by using chitosan-coated Prussian blue (PB) as a nanocarrier for silver nanoparticles anchoring. Combined with near-infrared (NIR) laser, the nanocompounds were more efficient at killing Escherichia coli (E. coli) and Methicillin-resistant staphyllococcus aureus (MRSA) in vitro. Notably, MRSA was significantly removed in vivo and promoted diabetic abscess healing by the combined therapy of this nanocompound and NIR laser, owing to the synergistic antibacterial effect of photothermal therapy and release of Ag + . Meanwhile, the nanocompound showed satisfactory biocompatibility and superior biosafety. Collectively, the combination therapy of this nanocompound with the assistance of NIR laser may represent a promising strategy for clinical anti-infection., Competing Interests: Declaration of Competing Interest The authors declare that they are not aware of any competing interests or personal relationships that might appear to have influenced the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

This work reports an improved enzyme-linked immunosorbent assay (ELISA) via the interaction between prussian blue nanoparticles (PBNPs) and amines for aflatoxin B1 (AFB1) detection. The effect of different amines on the structure and properties of PBNPs was systematically investigated. Amines with pK b  < 7, like ethylenediamine (EDA), can decompose structure of PBNPs, leading to the reduction of extinction coefficient and photothermal effect. Whereas, amines with large pK b  > 7, such as o-phenylenediamine (OPD), could undergo catalytic oxidation by PBNPs, resulting in the production of fluorescent and colored oxidation products. Accordingly, EDA and OPD were used to construct improved ELISA. Specifically, silica nanoparticles, on which AFB1 aptamer and amino binding agent (ethylenediaminetetraacetic acid disodium salt, EDTA•2Na) were previously assembled via carboxyl-amino linkage, are anchored to microplates by AFB1 and antibody. EDA concentration can be regulated by EDTA•2Na to affect extinction coefficient and photothermal effect of PBNPs, thereby achieving visual colorimetric and portable photothermal signal readout (Model 1). OPD concentration can also be controlled by EDTA•2Na, thus generating colorimetric and ultrasensitive fluorescent signals through PBNPs catalysis (Model 2). The proposed strategy not only opens new avenue for signal readout mode of biosensing, but also provides universal technique for hazards., 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. Published by Elsevier B.V.)

A two-stage method for 137Cs concentrating from seawater has been developed and adopted using composite ferrocyanide sorbents CFS Ni-K and CFS Zn-K(F). The suggested approach showed high efficiency that gives the opportunity to assess 137Cs content in the seawater without using low-background detectors. The data on 137Cs content has been obtained for the Japan, Okhotsk, and Bering seas using the suggested strategy. [ABSTRACT FROM AUTHOR]

In the process of producing gas reservoir, after the high salt formation water flows into the wellbore, the salt dissolved in the formation water will gradually separate out to form salt plugging due to the sharp decrease of temperature and pressure, resulting in the decrease of gas volume in gas wells. Chemical desalination is one of the important means to solve the problem of salt plugging. Sodium ferrocyanide was selected as an alternative inhibitor. Firstly, static technological parameters, such as inhibitor concentration, temperature, and service period were optimized, and the effect of pressure drop, temperature and flow rate on inhibitor performance was discussed. Then, the field application of the inhibitor in the blocked Daji 1 - 7 gas well was demonstrated. Results showed that the addition of sodium ferrocyanide significantly increased the chlorine ion concentration of formation water from 80.6 g/L to 144.1 g/L, which indicated that sodium chloride recrystallization was inhibited. Scanning Electron Microscopy (SEM) results revealed that the addition of the inhibitor induced the doping of several prismatic crystals into numerous dense small cubic crystals. The size of the cubic crystals reduced to 39 µm. The length of prismatic crystals in the presence of the inhibitor was only 200 µm and was less than that of crystals in the absence of the inhibitor. [ABSTRACT FROM AUTHOR]

Ferrocyanides with general formula AIxBIIy[Fe(CN)6], where A and B are cations, are thought to accept many substitutions on the A and B positions. In this communication, the synthesis and crystal structure of Cs²Sr[Fe(CN)6] are reported. The latter was obtained from K2Ba[Fe(CN)6] particles, put in contact with caesium and strontium ions. Hence, a simultaneous ion-exchange mechanism (Cs for K, Sr for Ba) occurs to yield Cs2Sr[Fe(CN)6]. The synthesis protocol shows that K2BaFe(CN)6 particles can be used for the simultaneous trapping of radioactive caesium and strontium nuclides in water streams. Cs2Sr[Fe(CN)6] adopts the cryolite structure type and is isotypic with the known compound Cs2Na[Mn(CN)6] [dicaesium sodium hexa­cyanidomanganate(III)]. The octa­hedrally coordinated Sr and Fe sites both are located on inversion centres, and the eightfold-coordinated Cs site on a general position. [ABSTRACT FROM AUTHOR]

In the present study electrochemical detection of a-lipoic acid (α-LA) was carried out with a poly(Vanillin) modified platinum electrode p(VA)/PtE in Brinton Robinson buffer (BR) solution. The platinum electrode surface's was modified with cyclic voltammetry method. The prepared Pt electrode was characterized by cyclic voltammetry in ferrocyanide and scanning electron microscopy (SEM) images. The number of cycles and scan rate effects were studied using square wave voltammetry (SWV) in BR buffer containing 1 mM α-LA. The electrochemical oxidation of α-lipoic acid on the modified Pt electrode is influenced by the pH and it is an irreversible reaction in which one electron and one proton are transferred. Electrolyte type and pH effect were studied. The anodic peak current shows a linear increase with α-LA concentrations ranging from 0.03 mM to 2.00 mM at pH 5, the detection limit being of 0.025 mM. The α-lipoic acid quantification in synthetic urine samples was made by SWV with the modified Pt electrode. [ABSTRACT FROM AUTHOR]