Prussian Blue Research Articles

Toxicity and antidotal treatment by synthesized and optimized ferric(III) hexacyanoferrate(II) for thallium

Abstract Background The active pharmaceutical ingredient (API) of USFDA-approved Radiogardase®-Cs capsule is ferric(III) hexacyanoferrate(II) which is commonly known as Prussian blue insoluble (PB). It enhances the elimination of radioactive or non-radioactive caesium/thallium (Cs(I)/Tl(I)) from the body. The API of Radiogardase®-Cs capsules is not available commercially; therefore, in-house API was synthesized and evaluated. The present study includes toxicity evaluation and in vivo Tl(I) removal efficacy of in-house synthesized and optimized PB prepared by direct (PB-1) and indirect (PB-2) synthesis methods. PB-1 and PB-2 were evaluated for acute and sub-acute oral toxicity in accordance with OECD guidelines in rats. Results No significant changes were observed in treatment groups as compared to the control group of acute and sub-acute oral toxicity studies. The food intake, water consumption, body weight, clinical signs, organ weight and histopathological, biochemical and haematological parameters were monitored. The study found no evidence of mortality. The results indicated that the synthesized PB-1 and PB-2 were safe. As a result, the study further examined PB-1 and PB-2 for removal of Tl(I) in rats. A significant increase in Tl(I) removal was observed when PB-1 and PB-2 were administered orally to rats in comparison to no treatment group. The Tl(I) removal efficacy of PB-1 and PB-2 was comparable to Radiogardase®-Cs treated group. Results showed reduction in the body burden of Tl(I) as well as a higher level of elimination of Tl(I) in faeces and urine. Conclusions The study provides substantial support regarding Tl(I) removal efficacy and safety of in-house synthesized PB-1 and PB-2 which can be used for formulation development.

Significantly enhanced alkaline stability and cyanide suppression of Prussian blue analogues using montmorillonite for high-performance cesium removal

Radiocesium (Cs+) treatment is getting more attention as Japan plans to dump wastewater from Fukushima nuclear meltdown into the Pacific Ocean. Prussian blue is a star material and medicine for intracellular and extracellular therapy of Cs+. However, it and its analogues are essentially unstable in alkali-solution and seawater due to break down easily into the hazardous cyanide substance. In this study, copper ferrocyanide/magnetic montmorillonite composites (KCuFC/M−MT) were prepared using an in-situ synthetic method. This method can inhibit the decomposition of Prussian blue analogues (PBAs) and the production of toxic cyanide. The 5KCuFC/M−MT composites exhibit excellent Cs+ adsorption properties (204.48 mg/g), good material chemical stable over a wide pH region (2 ≤ pH ≤ 12), safe amount of cyanide release (<0.2 mg/L, EPA, USA), and low-toxic to human hepatocytes (HepG2 cells), which are promising for the application in radioactive wastewater treatment. The adsorption mechanism and stabilization mechanism were systematically studied. This study provides a reference for the control radioactive Cs+ hazards by using clay material stabilized ferrocyanide material and provides a new direction for the research of cesium-control materials. This research solves the problem of basic instability of PBAs and expands new application fields for PBAs, especially decorporation agent for internal contamination by radiocesium.

Tracking intracellular nuclear targeted-chemotherapy of chidamide-loaded Prussian blue nanocarriers by SERS mapping

The novel histone deacetylase drug chidamide (CHI) has been proven to regulate gene expression associated with oncogenesis via epigenetic mechanisms. However, huge side effects such as non-targeting, poor intracellular accumulation and low nuclear entry efficiency severely restrict its therapeutic efficacy. Dual-targeted nanodrug delivery systems have been proposed as the solution. Herein, we developed a CHI-loaded drug delivery nanosystem based on Prussian blue (PB) nanocarrier, which combines surface-enhanced Raman scattering (SERS) tracking function with cancer cell/nuclear-targeted chemotherapy capability. With the property of background-free SERS mapping, PB nanocarriers can serve as tracking agents to localize intracellular CHI. The incorporation of targeted molecules specifically enhances the cancer cell/nuclear internalization and chemotherapeutic effects of CHI-loaded PB nanocarriers. In vitro cytotoxicity assay clearly shows that the constructed CHI-loaded PB nanocarriers have significant inhibitory on Jurkat cell proliferation. Furthermore, SERS spectral analysis of Jurkat cells incubated with the CHI-loaded PB nanocarriers reveals obvious features of cellular apoptosis: DNA skeleton fragmentation, chromatin depolymerization, histone acetylation, and nucleosome conformation change. Importantly, this CHI-loaded PB nanocarrier will provide a new insight for lymphoblastic leukemia targeted chemotherapy.

Killing three birds with one stone: Tumor-membrane-decorated Prussian blue nanovaccines for synergistic management of skin tumors, radiation dermatitis and wounds

Unhealed wounds following the resection of malignant skin tumors, featuring incomplete tumor tissue resection, full-thickness cutaneous defects, wound infection and radiation dermatitis, represent the main causes of prolonged recovery time, poor prognosis, and elevated tumor recurrence. Herein, a tumor cell membrane-decorated Prussian blue (PB) nanovaccine, referred to as PBVac, was fabricated via camouflage of PB nanozymes with the tumor cell membrane as tumor antigens and CpG oligodeoxynucleotides (ODNs) as adjuvants. Reinforcement by the tumor cell membrane substantially enhanced the tumor targeting potential of PBVac, achieving tumor-selective targeting and therapeutic efficacy. The bioactivity of PB nanozymes conferred PBVac with remarkable photothermal activity, antibacterial and antioxidant effects, curing wounds and radiation dermatitis by stimulating angiogenesis, antioxidation and anti-infection. The enhanced antitumor immunity of PBVac conferred by improved antigenicity was also assessed in a tumor challenge assay. PBVac could provide tumor antigens and molecular adjuvants for the priming of an efficient adaptive immune response, suppressing tumor growth. The combined merits of PBVac (photothermal, antibacterial and antioxidant capacities, and tumor membrane antigen) make it a novel nanoplatform that could be utilized as a safe and efficient therapeutic for synergistic management of skin tumors, radiation dermatitis and wounds.

Breaking the barriers: Engineering the crystalline-amorphous interface of Fe3O4@Fe electrode material for unparalleled energy storage and water splitting efficiency

Innovatively regulating the crystalline-amorphous (c-a) interface of electrode materials is critical for enhancing supercapacitor and electrochemical water splitting performance. In this research, an oxygen defect-rich Fe3O4@Fe electrode material with a unique and tunable c-a interface was synthesized using prussian blue (PB) as a template. The resulting interface facilitates electron transport and ion diffusion, increases the charge storage active sites, and enhances energy storage capacity. Density functional theory (DFT) simulations demonstrated that oxygen defects can effectively enhance ionic conductivity and facilitate electrochemical water splitting. The optimal Fe3O4@Fe electrode exhibits remarkable specific capacitance (1526.766 mF cm−2 at 1 mA cm−2) and exceptional oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) performance, with overpotential values of 231 and 359 mV at 10 mA cm−2, respectively. Furthermore, as an overall water splitting electrocatalyst, the optimal Fe3O4@Fe can reach 10 mA cm−2 at a battery voltage of 1.645 V, demonstrating its tremendous potential as a highly efficient electrocatalyst.

Novel Electrochemiluminescent Immunosensor Using Dual Amplified Signals from a CoFe Prussian Blue Analogue and Au Nanoparticle for the Detection of Lp-PLA2.

Coronary heart disease (CHD) poses an important threat to human health, and its pathogenesis is the formation of atheromatous plaques in coronary ventricles. Compared to other biomarkers, lipoprotein-associated phospholipase A2 (Lp-PLA2), which is involved in multiple processes of atherosclerosis, is a noticeable inflammatory biomarker related to CHD. Herein, using a multifunctional nanocomposite containing a CoFe Prussian blue analogue (PBA) and Au nanoparticles (AuNPs) (AuNPs@CoFe PBA) as a sensing substrate, an electrochemiluminescent (ECL) immunosensor was developed for the highly sensitive detection of Lp-PLA2. Benefiting from the synergistic effect of the PBA and AuNPs, the nanocomposite exhibits excellent peroxidase-like activity and can catalyze the luminol-ECL reaction, amplifying the ECL signal by ∼29-fold. Meanwhile, the enlarged specific surface area of the nanocomposite and the presence of abundant AuNPs allow the immobilization of more antibody proteins, thereby improving the sensing response of the immunosensor. When the target Lp-PLA2 is captured by the antibody on the sensor surface, the sensor emits a reduced ECL signal because of the increased mass and electron transfer resistance due to the formation of the immune complex. Under optimized conditions, the constructed ECL immunosensor exhibits a broad linear range from 1 to 2200 ng/mL and a low detection limit of 0.21 ng/mL. Additionally, the ECL immunosensor exhibits high specificity, stability, and reproducibility. This work provides a new approach to diagnose CHD and broadened the application of the PBA in the field of ECL sensors.

Multianalytical Study of the Blue Pigments Usage in Serbian Iconography at the Beginning of the 18th-Century

Traditional Serbian religious art originated in Byzantine culture and conserved Byzantine elements until modern times. However, since the end of the 17th century, many changes in traditional icon painting have been introduced. Previous studies focused on the changes in iconography and style, but very little attention was paid to the changes in painting materials and techniques. This research focuses on the blue pigments on icons from the first half of the 18th century. Eight icons with blue areas of a different hue were selected for the study. Due to its rarity in nature, price, and iconographical importance, the blue pigment was particularly praised by painters. Therefore, the choice of the blue pigment can be related to historical information to trace influences and the development of the painter’s practice. Imaging techniques, several portable, non-destructive analytical techniques, such as XRF and FTIR, followed by optical microscopy and SEM-EDX analysis of the samples were used to characterize blue pigments and the painting technique. An analysis showed that icon painters at the beginning of the 18th century used pigments such as azurite, an indigo-organic colourant of plant origin, and Prussian blue. Contrary to the traditional belief that natural ultramarine blue was used, it was not confirmed in any studied examples.

The Goiânia incident, the semiotics of danger, and the next 10,000 years

The Goiânia Incident In September 1987, two men in Goiânia, Brazil, discovered an abandoned international standard capsule containing less than 100 g of cesium-137 chloride. The material was unguarded, and the warning systems were inadequate and inscrutable. The men took the capsule and sold it for scrap, and within days the city would be contaminated with highly radioactive material. Within weeks, 112,000 individuals would be screened for radioactive contamination, 249 would be exposed to radioactive materials, 46 would receive medical treatment for radioactive contamination, and four would die from acute radiation sickness. The citywide radioactive contamination occurred, in part, due to arbitrary and unfamiliar written warning systems. The individuals who discovered the cesium-137 capsule were illiterate and unfamiliar with the radiation trefoil logo, which was first used in 1946 in California, United States of America. As a result, written language and visual symbols were useless warnings against the dangerous contents of the capsule. Management of cesium-137 exposure in 2023 Cesium-137 enters the body through ingestion or inhalation. This isotope emits beta and gamma radiation, both forms of ionizing radiation which damage living tissues. The radiation dose lethal to 50% of an exposed population within 60 days (LD50/60) is approximately 3.5 to 4 Gray (Gy) without medical intervention. However, this dose increases to around 6-7 Gy when medical support is provided, which typically includes antibiotics, blood transfusions, granulocyte-macrophage colony-stimulating factor, and Prussian blue. Prussian blue binds to cesium, thereby facilitating its elimination from the body. Lessons learned regarding radioactive waste disposal and the next 10,000 years The radiological disaster in Goiânia was due in large part to the failures of various agencies to warn of danger and minimize access to radioactive material. Barriers to risk communication included a lack of a universal semiotic language regarding radioactive hazards, which was compounded by the illiteracy of the scrappers and their inability to recognize the radioactivity warning trefoil. There is no society in which every member understands written language or recognizes every symbol. Given that the teletherapy unit was abandoned in an urban environment, there were no administrative or engineering controls in place to prevent human beings from becoming exposed to radioactive material. Conclusions As little as 100 g of highly radioactive material, such as cesium-137, may lead to massive environmental contamination, fatalities and permanent disability due to acute radiation sickness, wreak havoc, and disrupt society on a scale that is challenging for public health officials to manage. Thousands of tons of radioactive materials from the waste products of nuclear weapons and power plant manufacture will have to be stored for at least 100,000 years to prevent danger to human life and society. Public health officials and governments must build systems to keep humans safe and physically isolated from these radioactive materials for as long as possible.

Construction of a SERS platform for sensitive detection of aflatoxin B1 based on CRISPR strategy.

Aflatoxin B1, a pathogen in the aflatoxin family, has attracted much attention due to the harmfulness in production and life. However, the common methods like high performance liquid chromatography used for detection of AFB1 have deficiency in complicated pretreatment processes, and the purification effect is not ideal. Herein, a SERS platform based on CRISPR strategy was designed for sensitive detection of AFB1. By synthesizing core-shell nanoparticles embedded with Raman silent region dye molecules, Prussian blue (PB), the detection of the sensor reduced background interference and the SERS signal was calibrated. At the same time, the high-efficiency reverse cleavage activity of cas12a was used to convert non-nucleic acid targets into nucleic acid, so as to achieve the effect of sensitive detection of AFB1 with a detection limit of 3.55 pg/mL. This study provides a new thought for SERS detection of non-nucleic acid targets in the future.

Determination of Cyanide at Trace Levels by Computational Scanning Densitometry

Introduction: Cyanide is one of the most commonly present anions in industrial effluents, highly toxic to human and animal life. Therefore, its determination in aqueous media by simple, portable, and quick methods is required. Objective: This study aims to develop a simple and quick method to determine this anion at the micro level in aqueous media without using any expensive instrument. Method: The method is based on treating the microliter sample of aqueous cyanide with the classical Lassaigne’s reagents on a TLC plate. After heating in an oven for a few minutes, a deep blue spot of ferric ferrocyanide complex appeared on the plate. The color depth of the spots was measured by scanning the TLC plate and analyzing the image with an indigenous software package. Result: As a result of fusion with metallic sodium, carbon and nitrogen of the organic compound combine to form cyanide, which first reacts with Fe(II) to form hexacyanoferrate ion [Fe(CN)6]4- that further combines with Fe(III) to create a neutral deep blue colored coordination complex, ferric ferrocyanide Fe4[Fe(CN)6]3. Discussion: This process converts real-world colors into numeric computer data consisting of rows and columns of pixels. Each pixel will consist of three numeric components, i.e., red, green, and blue. The pixel's color will be one of 16.8 million possible color combinations (256 shades of red, green, and blue each). Conclusion: From the comparison of results obtained by the proposed method and standard ion-selective electrode method, it can be concluded that the former method for determining micro quantities of cyanide in aqueous samples using computational densitometry is a simple, accurate, and adequately precise method without the involvement of sophisticated instrumentation.

Multicolor aptasensors for pesticide multiresidues detection in agricultural products using bioorthogonal surface-enhanced Raman scattering tags

Realizing accurate pesticide multiresidue detection in a complex matrix is still a challenge for point-of-care sensing methods. Herein, we introduced background-free and multicolor aptasensors based on bioorthogonal surface-enhanced Raman scattering (SERS) tags and successfully applied them to analyze multiple pesticide residues. The excellent anti-interference and multiplex capability are due to the application of three bioorthogonal Raman reporters involving 4-ethenylbenzenamine (4-EBZM), Prussian blue (PB) and 2-amino-4-cyanopyridine (AMCP) with alkynyl and cyano groups, which demonstrated apparent Raman shift peaks at 1993 cm−1, 2160 cm−1, and 2264 cm−1 in the biologically Raman-silent region, respectively. Ultimately, a detection range of 1–50 nM for acetamiprid, atrazine and malathion was achieved with detection limits of 0.39, 0.57 and 0.16 nM, respectively. The developed aptasensors were successfully used to determine pesticide residues in real samples. These proposed multicolor aptasensors offer an effective strategy for pesticide multiresidue detection with advantages of anti-interference, high specificity and high sensitivity.

An electrode for a high-performance asymmetric supercapacitor made of rGO/PANI/PB ternary nanocomposite

The electrodeposition technique was used to create Prussian blue (PB), binary: rGO/PB, PANI/PB, rGO/PANI, and ternary: rGO/PANI/PB nanocomposites. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and Brunauer–Emmett–Teller (BET) methods were used to describe the samples. The results demonstrated the covering of PB by the rGO and PANI. The electrochemical characteristics of the studied materials were examined using cyclic voltammetry (CV), galvanostatic charge and discharge (GCD), and electrochemical impedance spectroscopy (EIS) in 2 M Na2SO4. The specific capacitance follows the order: rGO/PANI/PB > rGO/PB > PANI/PB > rGO/PANI> PANI > rGO > PB. The rGO/PANI/PB nanocomposite electrode exhibits a specific capacitance of 336 F. g−1 in 2 M Na2SO4 at a discharge current density of 1 A. g−1 with 92 % retention of its original capacitance after 3000 cycles. The remarkable electrochemical performance of the ternary rGO/PANI/PB nanocomposite is attributed to its synergistic effects among individual components. The ternary electrode's high electrochemical performance indicates that it might be employed as an electrode for commercial supercapacitors. An asymmetric supercapacitor (ASC) was built using a positive electrode of rGO/PANI/PB and a negative electrode of activated carbon (AC). The arranged (ASC) operates continuously within the potential range of 0–1.8 V and delivers a high energy density of 56.3 Wh. kg−1 at a power density of 8804 W. kg−1, as well as 92 % retention of its original capacitance after 3000 cycles.

An Injectable and Antifouling Supramolecular Polymer Hydrogel with Microenvironment-Regulatory Function to Prevent Peritendinous Adhesion and Promote Tendon Repair.

The imbalance of extrinsic and intrinsic healing of tendon is thought to be the main cause of peritendinous adhesions. In this work, we prepare an injectable supramolecular poly(N-(2-hydroxypropyl) acrylamide) (PHPAm) hydrogel merely via side chain hydrogen-bonding crosslinks. This PHPAm exhibits good antifouling and self-healing properties. The supramolecular hydrogel simultaneously loaded with Prussian blue (PB) nanoparticles and platelet lysate (PL) is exlpored as a functional physical barrier, which could significantly resist the adhesion of fibrin and fibroblasts, attenuate the local inflammatory response, and enhance the tenocytes activity, thus balancing extrinsic and intrinsic healing. The PHPAm hydrogel is shown to prevent peritendinous adhesions considerably by inhibiting NF-κB inflammatory pathway and TGF-β1/Smad3-mediated fibrosis pathway, thereby significantly improving tendon repair by releasing bioactive factors to regulate the tenocytes behavior. This work provides a new strategy for developing physical barriers to prevent peritendinous adhesions and promote tissue repair effectively. This article is protected by copyright. All rights reserved.

Photothermal and Catalytic Performance of Multifunctional Cu-Fe Bimetallic Prussian Blue Nanocubes with the Assistance of Near-Infrared Radiation.

Copper and iron are the basic metal elements that have attracted much attention in industry. Prussian blue (PB) is a significant class of metal-organic frameworks (MOFs); however, the lack of such linkages between the structure and properties, as well as properties differences, limits their potential applications. In this paper, the Cu-based Prussian blue nanocubes with and without Fe doping were synthesized. With the increasing reaction time, the morphology of the Cu-based Prussian blue nanocubes without Fe doping (PB:Cu NCs) changes from cuboidal to circular, and finally grows back to cuboidal. However, Cu-based Prussian blue nanocubes with Fe doping (PB: CuFe NCs) grow directly from the cube and eventually collapse. The nanocubes show a notable red shift with the tunable spectra from 400 nm to 700 nm. Compared with PB: Cu NCs, the PB: CuFe NCs have higher temperature rise under 808 nm irradiation and better photothermal efficacy. The catalytic efficiency of PB: CuFe NCs changes with the pH and reaches its maximum value of 1.021 mM with a pH of 5.5. The enhanced catalytic reaction by the near-infrared radiation plasmonic photothermal effect is also confirmed. This work highlights the potential of the developed PB: Cu and PB: CuFe NCs for photothermal-enhanced co-catalysis nanomaterials.

Iron-based hybrid polyionic complexes as chemical reservoirs for the pH-triggered synthesis of Prussian blue nanoparticles

HypothesisHybrid polyion complexes (HPICs) obtained from the complexation in aqueous solution of a double hydrophilic block copolymer and metal ions can act as efficient precursors for the controlled synthesis of nanoparticles. In particular, the possibility to control the availability of metal ions by playing on the pH conditions is of special interest to obtain nanoparticles with controlled size and composition. ExperimentsHPICs based on Fe3+ ions were used to initiate the formation of Prussian blue (PB) nanoparticles in presence of potassium ferrocyanide in reaction media with varying pH values. FindingsComplexed Fe3+ ions within HPICs can be easily released by adjusting the pH value either through the addition of a base/acid or by using a merocyanine photoacid. This allows to modulate the reactivity of Fe3+ ions with potassium ferrocyanide present in solution. As a result, PB nanoparticles with different structures (core, core–shell), composition and controlled size are obtained.

Efficient lithium extraction using redox-active Prussian blue nanoparticles-anchored activated carbon intercalation electrodes via membrane capacitive deionization

Global demand for lithium (Li) resources has dramatically increased due to the demand for clean energy, especially the large-scale usage of lithium-ion batteries in electric vehicles. Membrane capacitive deionization (MCDI) is an energy and cost-efficient electrochemical technology at the forefront of Li extraction from natural resources such as brine and seawater. In this study, we designed high-performance MCDI electrodes by compositing Li+ intercalation redox-active Prussian blue (PB) nanoparticles with highly conductive porous activated carbon (AC) matrix for the selective extraction of Li+. Herein, we prepared a series of PB-anchored AC composites (AC/PB) containing different percentages (20%, 40%, 60%, and 80%) of PB by weight (AC/PB-20%, AC/PB-40%, AC/PB-60%, and AC/PB-80%, respectively). The AC/PB-20% electrode with uniformly anchored PB nanoparticles over AC matrix enhanced the number of active sites for electrochemical reaction, promoted electron/ion transport paths, and facilitated abundant channels for the reversible insertion/de-insertion of Li+ by PB, which resulted in stronger current response, higher specific capacitance (159 F g−1), and reduced interfacial resistance for the transport of Li+ and electrons. An asymmetric MCDI cell assembled with AC/PB-20% as cathode and AC as anode (AC//AC-PB20%) displayed outstanding Li+ electrosorption capacity of 24.42 mg g−1 and a mean salt removal rate of 2.71 mg g min−1 in 5 mM LiCl aqueous solution at 1.4 V with high cyclic stability. After 50 electrosorption-desorption cycles, 95.11% of the initial electrosorption capacity was retained, reflecting its good electrochemical stability. The described strategy demonstrates the potential benefits of compositing intercalation pseudo capacitive redox material with Faradaic materials for the design of advanced MCDI electrodes for real-life Li+ extraction applications.

Fabrication of self-assembled Prussian blue graphene hydrogel for highly selective removal of radioactive cesium in water: Adsorption study

This paper reports a simple and cost-effective method for fabrication of a 3D porous and redox-active Prussian blue-graphene (PBG) hydrogel using ferrous ions to reduce graphene oxide sheets. The hydrogel was obtained via sonication for 5 min only at a low temperature of 40 °C without the need of purification or centrifugation. The hydrogel exhibited high selectivity for cesium ions due to the cubic framework of iron centers bound by cyanide bridges, which allows for intercalation of additional cations. The hydrogel's centered-cubic phase of Prussian blue was confirmed through XRD, and its existence was demonstrated through FTIR and XPS. The BET surface area measurements revealed that the composite's adsorptive surface area increased as compared to magnetic PBGO. Furthermore, the hydrogel's adsorption potential for cesium ions increased to 4.67 mmol/g (621.11 mg/g) compared to the previous work, fitting well with the Langmuir isotherm and the pseudo-second order kinetic model. Moreover the optimal values for temperature and pH for cesium ions removal were found to be 30 °C and neutral, respectively.

3D Neighborhood Nanostructure Reinforces Biosensing Membrane

AbstractThe electron signals in the cell can be rapidly and accurately transmitted by the spatially confined and adjacently distributed enzyme pairs anchored in the cytomembrane. As inspiration, by leverage of tannic acid‐3‐aminopropyltriethoxysilane‐Fe (TA‐APTES‐Fe) ternary coating, for the first time, a mesoporous biosensing membrane is developed by orderly assembly and targeted confinement of Prussian blue (PB) and glucose oxidase (GOx) with neighborhood nanostructure in the 3D mesoporous carbon nanotubes (CNTs) membrane electrode. The mesoporous biosensing membrane extends the triple‐phase boundary from conventional 2D contact to 3D contact, promotes the transfer rates of the cascade reactants, enhances the proximity of PB, GOx, and the electrode, and achieves in–situ removal of interferents, thereby elevating the utilization of PB, enhancing the cascade reaction efficiency, increasing the availability of the electroactive hydrogen peroxide (H2O2), and improving its stability. It exhibits superior sensitivity (31.2 µA mM−1) and long‐term stability in continuous glucose monitoring with a negligible response drift for up to 8 h. In addition, the multienzyme mimic functions of PB are employed to imitate the “loosening‐degradation” membrane cleaning process via bubble scrubbing and Fenton oxidation, thereby fully regenerating the fouled biosensing membrane. This work provides a novel design strategy for biosensors toward efficient, reliable, and stable sensing.

Erythrocyte-Cancer Hybrid Membrane-Camouflaged Prussian Blue Nanoparticles with Enhanced Photothermal Therapy in Tumors.

Prussian blue (PB) nanoparticles have been widely used in photothermal therapy research due to the efficient photothermal conversion ability. In this study, PB was modified with a bionic coating using a hybrid membrane of red blood cell membranes and tumor cell membranes to prepare bionic photothermal nanoparticles (PB/RHM), which can further improve the blood circulation ability and tumor targeting of the nanoparticles to achieve efficient photothermal therapy for tumor treatment. In vitro formulation characterization showed that PB/RHM was a monodisperse spherical core-shell structured nanoparticle with a diameter of 207.2 nm and effectively retained the cell membrane proteins. The in vivo biological evaluation results showed that PB/RHM could effectively accumulate into the tumor tissue, inducing a rapid temperature increase in the tumor site to 50.9 °C within 10 min, inhibiting tumor growth efficiently with a tumor inhibition rate of 93.56% and with good therapeutic safety. In summary, this paper provided a hybrid film-modified Prussian blue nanoparticle with efficient photothermal anti-tumor capacity and safety.

Structural regulation of Mn-based Prussian blue induced by zinc-substitution for enhanced sodium storage performance

Mn-based Prussian blue (NMF) is a prospective choice for sodium-ion battery cathode materials because of its high theoretical specific capacity, high charge/discharge voltage plateau, cheap raw materials and eco-friendly. However, it undergoes serious capacity fading during cycling owing to the unstable Jahn-Teller distortion caused by the oxidation of Mn2+ to Mn3+. In this work, the structural regulation of NMF is achieved through zinc substitution, and the effect of structural adjustment caused by zinc substitution on the sodium storage properties of NMF is studied in detail. The experimental results verify that NZMF still maintain cubic structure with high content of sodium, less [Fe(CN)6] vacancies and low level of crystal water. Moreover, the four coordination of Zn-N is lower than six coordination of Mn-N, confining the nucleus growth, thereby reducing the powders size of NZMF. The smaller powder size of NZMF with higher surface area results in shortened sodium ion diffusion path and accelerated the charge transfer. In addition, the electrochemically inactive zinc plays a pillar role in maintaining its structural stability. Consequently, NZMF reveals better rate capacity and cycling stability than original NMF. In particular, its capacity can be maintained at 68.6 mAh g−1 under a high current density of 1600 mA/g, and the capacity retention is 76.5% at 800 mA/g after 1000 cycles. This work provides a new insight to improve the structural stability of Prussian blue.