Bimetallic Oxide Nanoparticles Research Articles

Flexible Ni‐Based Bimetallic Spinel Oxide (NiM2O4, M = Mn, Fe, Co) Electrodes for Supercapacitor Applications

Herein, the single‐phase Ni‐based bimetallic spinel oxide (NiM2O4, M = Mn, Fe, Co) nanoparticles are successfully synthesized by sol–gel method and coated on a carbon cloth substrate to form flexible electrodes for supercapacitor applications. The effects of transition metal activity, calcination temperature, surface, and textural properties on the electrochemical properties of spinel electrode materials are demonstrated. It is found that lowering the calcination temperature results in a decrease in crystallite size and particle size, leading to an increase in surface area and pore volume. X‐Ray absorption spectroscopy reveals the presence of Mn2+/3+, Fe2+/3+, and Co2+/3+ in materials. According to the electrochemical studies, NiMn2O4 electrode in Na2SO4 electrolyte exhibits electrical double‐layer capacitance behavior, while NiFe2O4 and NiCo2O4 electrodes in KOH electrolyte exhibit pseudocapacitive behavior. All electrode materials have low solution resistance and charge transfer resistance. NiCo2O4 provides the highest specific capacitance (85.60 F g−1 at 2.5 A g−1) followed by NiFe2O4 and NiMn2O4. It seems likely that the high electrochemical activity of Co2+/3+ and small particle size of NiCo2O4 nanoparticles play an important role in improving the redox process and charge transfer, which may enhance the electrochemical performance of this electrode material.

Mycofabrication of bimetal oxide nanoparticles (CuO/TiO2) using the endophytic fungus Trichoderma virens: Material properties and microbiocidal effects against bacterial pathogens

Bimetallic oxide nanoparticles (NPs) have gained the interest of researchers owing to the synergistic mechanism of action by the elements present. Mycosynthesis of nanostructures is a promising, facile, and an environmentally friendly approach. In the present study, CuO/TiO2 NPs were produced using the cell-free filtrate of the endophytic fungus Trichoderma virens. The reaction of the fungal filtrate with the two metal salts, CuSO4.5H2O and TiO2, resulted in the mycosynthesis of the CuO/TiO2 NPs. The prepared bimetal oxide NPs were characterized using XRD, FTIR spectroscopy, EDX, DLS, zeta potential analysis, XPS, Raman scattering, FESEM, and HRTEM. The mycosynthesized CuO/TiO2 NPs exhibited diffraction peaks characteristic of the monoclinic CuO and tetragonal rutile TiO2 crystal planes. Homogeneity and stability were observed as a result of the biological moieties present in the fungal filtrate, which capped the CuO/TiO2 NPs. The prepared CuO/TiO2 NPs were distributed as flake/plate-like and quasi-spherical/nanorod CuO and TiO2 NPs, respectively. A broad-spectrum antibacterial effect was recorded, with zones of inhibition as follows: foodborne pathogens Escherichia coli (14.34 mm), Salmonella enterica serovar Typhimurium (11.32 mm), and Staphylococcus aureus (9.63 mm); and phytopathogenic bacteria involving Clavibacter michiganensis subsp. michiganensis (Cmm, 12.16 mm), C. michiganensis subsp. capsici (Cmc, 11.26 mm), wild type and streptomycin-resistant Pectobacterium carotovorum subsp. carotovorum (Pcc, 11.06 and 12.37 mm, respectively), and wild type and streptomycin-resistant Xanthomonas citri pv citri (Xcc, 12.48 and 12.69 mm, respectively). The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of the CuO/TiO2 NPs were determined using the broth microdilution assay. NP-treated bacterial cells at sub-MICs had rough surfaces with membrane defects and exhibited shrinkage, reduction of cell edges, cracks, and fractures on their surfaces. This study provides insights into the potential of the mycosynthesized CuO/TiO2 NPs as alternative nano-antimicrobial agents, which could be employed for future biomedical, agricultural, and pharmaceutical applications.

Morphostructural studies of pure and mixed metal oxide nanoparticles of Cu with Ni and Zn

Nano-scale interactions between pure metal or metal-oxide components within an oxide matrix can improve functional performance over basic metal oxides. This study reports on the synthesis of monometallic (CuO), bimetallic (CuO–NiO) and trimetallic (CuO–NiO–ZnO) oxide nanoparticles (NPs) via the co-precipitation method and investigation of morphostructural properties. All of the synthesized metal oxide NPs were calcined at 550 °C temperature and annealed under vacuum. In this work, we applied Scherrer formula, modified Scherrer equation, Williamson-Hall plots, and Halder-Wagner plots to calculate the average crystallite size. The XRD data analysis showed that average crystallite sizes of the as-synthesized metal oxide phases were between 4 nm and 76 nm and average diameters calculated from SEM image were between 15 nm and 83 nm. The XRD studies also disclosed that average crystallite size and lattice microstrain of the CuO phases remain almost same (43 nm–46 nm and 2.074×10−3 to 2.665×10−3) for pure CuO and mixed CuO–NiO; but in case of mixed CuO–NiO–ZnO it is found to decrease in size to 11 nm where lattice microstrain increases to 9.653×10−3. Line broadening of diffraction peaks from microstrain contribution was between 0.02 and 0.01. Degree of crystallinity (%) of CuO phases found to decrease from 81 to 71. Dislocation density of CuO phases found to increase from 6.63×10−4nm−2 to 12.68×10−3nm−2. X-ray density of CuO phases increased from 6.48 to 6.53 g/cm3. Where this calculated small dislocation density well agreed with the high crystallinity. Crystal structure and specific surface area were determined from lattice constants and X-ray density. These synthesized nanopowders showed the existence of monoclinic, cubic, and hexagonal phases. The obtained NPs of multi-metal oxide explained more than one phases with different size, shape, and morphology at nano scale.

Synthesis and photocatalytic properties of zinc-copper bimetallic oxide nanoparticles for removal of reactive blue 19 dye in aqueous suspension

ABSTRACT This research investigates the photocatalytic removal of reactive blue 19 (RB19) dye utilising Zn-Cu (zinc-copper) bimetallic oxide nanocatalysts under UV irradiation. The nanocatalysts were prepared via the co-precipitation technique and thoroughly characterised using different procedures including XRD, FTIR, BET-BJH, FESEM, TEM, and EDX. BET-BJH analysis revealed a specific surface area of 59.774 m2/g for the Zn-Cu bimetallic oxide nanocatalyst. Response surface methodology (RSM) was employed to optimise operational factors such as catalyst amount, pH, H2O2 amount, and UV power, with a quadratic model showing high reliability (R2 = 0.89). Under optimal conditions (4 mg catalyst amount, pH 6.68, 0.42 mL H2O2 dose, 23 W UV power, and 45 min reaction time), the maximum RB19 removal reached 77.14%, increasing to 98.33% after 120 min. The kinetic study revealed a reaction rate constant of 0.884 min−1, indicating efficient removal. Zn-Cu bimetallic oxides demonstrated superior RB19 removal capacity, with only a 5.92% reduction in removal yield after 5 consecutive reuse cycles. This study underscores the potential of Zn-Cu bimetallic oxide nanocatalysts for efficient removal of RB19 dye in suspension media.

Harnessing bimetallic oxide nanoparticles on ionic liquid functionalized silica for enhanced catalytic performance

The present study reports on harnessing bimetallic (V and Ni) oxide nanoparticles supported on ionic liquid-functionalized silica for enhancing catalytic performance in epoxidation and hydrogenation reactions. The as-synthesized catalyst was ably characterized through various techniques such as FTIR, X-ray diffraction (XRD), N2 adsorption−desorption isotherms, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). A selective organic transformation of Isophorone to Homalinol via two-steps tandem reaction significantly promoted by synthesized catalyst. During epoxidation and hydrogenation reactions, V-NiNPs@SILP catalyst demonstrated excellent catalytic performance, leading to 98.23 % conversion with 99.06 % selectivity. Moreover, the synthesized catalyst exhibited recyclability for five consecutive cycles with minute loss in activity.

Synergistic electrochemical sensing of 2,4-dinitrotoluene via bimetallic nickel-cobalt oxide nanoparticles

This study presents a comprehensive investigation into the synthesis, characterization, and application of an exceptionally sensitive electrochemical sensor designed for the ultrasensitive detection of 2,4-dinitrotoluene (DNT), a notorious explosive compound. The sensor employs bimetallic nickel-cobalt oxide (NiCo2O4) nanoparticles, synthesized through a facile hydrothermal method. Extensive analytical techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), and x-ray photoelectron spectroscopy (XPS), were employed to validate the crystallinity and purity of the NiCo2O4 nanoparticles. These nanoparticles, possessing remarkable properties, form the core of our electrochemical sensor, enabling it to offer heightened sensitivity and selectivity even under ambient conditions. Most notably, this sensor boasts an impressively low limit of detection (LOD) of 18 nM, coupled with a broad linear detection range (LDR) spanning from 10 nM to 100 nM. The sensor exhibits robust sensitivity, excellent selectivity, and an outstandingly low detection threshold, collectively demonstrating its potential for precise and accurate detection of DNT. This research underscores the significant potential of bimetallic oxide nanoparticles, specifically NiCo2O4, in the precise quantification of nitro-aromatic analytes. This study opens up promising avenues for assessing hazardous compounds in complex environmental matrices, thereby contributing to the advancement of electrochemical sensing. Additionally, this novel sensing platform holds substantial promise for enhancing security measures and environmental monitoring through its improved sensitivity and selectivity in the detection of explosives.

Effect of ZnMgO2 nanoparticles used as a nanofertilizer: promoting the growth activities of rice seedlings

Novel ZnMgO2 bimetallic nanoparticles were synthesized using Cinchona succirubra leaf extract and used as a nano fertilizer, promoting the growth activities of rice seedlings, α-amylase and antioxidant activity with average particle sizes of 24.8 nm.

Pyridinic and Pyrrolic-N induced carbon nanotubes support bimetallic oxide nanoparticles as high-performance electrocatalysts for oxygen reduction reaction

In-expensive MnO2-based nanostructure has been considered the ideal electrode material for oxygen reduction reaction (ORR) in fuel cell technology. Regardless of their highly active ORR performance, the fuel cross-over capacity and stability of MnO2-based catalysts are still far from satisfying. Herein, we report the highly active SnO2 nanoparticles (NPs) integrated on N-induced carbon nanotube (SnO2@NC) are combined with MnO2 nanoparticles through the electrodeposition to form effective nanostructured in which the MnO2 NPs and SnO2@NC in situ grown on a glassy carbon electrode (MnO2/SnO2@NC) with well-controlled reaction parameters, that exhibits superior ORR activity for the first time. We assessed the marginal role of pyridinic-N and pyrrolic-N in the electrocatalytic ORR activity, synthesis of MnO2/SnO2 bimetallic oxide electrocatalysts, and distribution behavior of NPs. Bimetallic MnO2/SnO2@NC electrode has unique synergistic interactions between MnO2/SnO2 NPs and NC support, which increases electro-active sites, and fast charge transfers towards ORR as compared to other as-prepared electrodes on account of the rational design of the electrode-electrolyte interface plays a significant role in expediting the ORR kinetics. Additionally, the surface nanostructure features, crystalline structure, as well as electronic chemical states of the MnO2/SnO2 NPs embedded in N-induced CNTs, were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Furthermore, bimetallic MnO2/SnO2@NC nanostructure leads an outstanding ORR performance in the 0.1 M KOH electrolyte, delivering a halfwave potential (-0.878 V) and remarkable limiting current density (-4.14 mA cm−2) and much better tolerance to the ethanol cross-over effect with high stability. Thus, the present strategy opens a new path to the design of a pyridinic-N and pyrrolic-N-oriented bimetallic oxide nanostructure as a high-active electrocatalyst for ORR application.

Design and synthesis of hierarchical MnO–Fe3O4@C/expanded graphite composite for sensitive electrochemical detection of bisphenol A

Hierarchically nanostructured binary transition metal oxide-based materials with high conductivity and catalytic activity are quite attractive for the electrochemical quantitative detection of environmental pollutants due to their natural abundance, variable oxidation state, and excellent synergies between metal sites. Herein, a new hierarchical MnO–Fe3O4@C/expanded graphite (EG) composite is designed and synthesized through a simple and in situ annealing method with the utilization of bimetallic organic framework (FeMn-MOF)/EG precursor. The synthesized MnO–Fe3O4@C/EG composite possesses a unique hierarchical nanoarchitecture that small-sized bimetallic oxide nanoparticles of 10–40 nm completely encapsulated by amorphous carbon layers of 2–4 nm are uniformly distributed on the EG platform. This distinctive structure combines the advantages of high conductivity, excellent catalytic activity, and strong stability. Resultantly, when it is applied to monitor environmental endocrine disruptors, the sensor exhibits a significant catalytic effect on the electrochemical oxidation of bisphenol A (BPA), inducing an amplified response current. In addition, the sensor shows a wide linear range of 1–50 μM and 50–400 μM for the BPA monitor, giving a sensitivity of 5208.8 and 1641.9 μA mM−1 cm−2, respectively. This study offers a new approach to design hierarchical binary metal oxide-based sensing materials as well as to explore their electrochemical properties and applications for the determination of emerging contaminants.

Bimetallic oxide Mg-Cu nanoparticles synthesis and application in photometric sensing of trypsin in the presence of tap water, ammonia, and glutamine

The concentration of biomolecules such as trypsin and ammonia in bodily fluids are indicators of health conditions including pancreatic diseases and acute liver failure respectively. The maximum UV-Visible intensity and wavelength shifts of Mg-Cu bimetallic oxide nanoparticles (BNPs) were found to be proportional to changes in trypsin and ammonia concentration. The BNPs could selectively detect trypsin in tap water containing ions, ammonia, and glutamine at concentrations as low as 0.0003%v/v. The synthesis of Mg-Cu BNPs was accomplished by ablating a mixture of Mg and Cu powders and Mg and Cu colloids using a Nd:YAG 1064 nm laser in isopropanol alcohol and HCl. The BNPs demonstrated higher optical absorbance intensity in the UV-Visible range compared to their monometallic constituents, making them more suitable for use in biochemical sensing of trypsin and ammonia. The BNPs exhibited a massive 730-fold increase in electrical conductivity compared to monometallic Mg nanoparticles (0.001 mS/cm vs. 0.73 mS/cm). Field emission scanning electron microscopy was used to visualize the NP morphologies, revealing pyramidal and quasi-spherical BNPs with diameters as small as 5 nm.

Enhanced Photocatalytic Degradation of Malachite Green Dye Using Silver-Manganese Oxide Nanoparticles.

Efficient and excellent nanoparticles are required for the degradation of organic dyes in photocatalysis. In this study, silver-manganese oxide nanoparticles (Ag-Mn-NPs) were synthesized through a wet chemical precipitation method and characterized as an advanced catalyst that has enhanced photocatalytic activity under sunlight irradiation. The nanoparticles were characterized using scanning electron microscopy (SEM), XRD, UV-vis light spectra, and energy-dispersive X-ray (EDX) spectroscopy, revealing their spherical and agglomerated form. The EDX spectra confirmed the composition of the nanoparticles, indicating their presence in oxide form. These bimetallic oxide nanoparticles were employed as photocatalysts for the degradation of malachite green (MG) dye under sunlight irradiation in an aqueous medium. The study investigated the effects of various parameters, such as irradiation time, catalyst dosage, recovered catalyst dosage, dye concentration, and pH, on the dye's photodegradation. The results showed that Ag-Mn oxide nanoparticles exhibited high photocatalytic activity, degrading 92% of the dye in 100 min. A longer irradiation time led to increased dye degradation. Moreover, a higher catalyst dosage resulted in a higher dye degradation percentage, with 91% degradation achieved using 0.0017 g of the photocatalyst in 60 min. Increasing the pH of the medium also enhanced the dye degradation, with 99% degradation achieved at pH 10 in 60 min. However, the photodegradation rate decreased with increasing dye concentration. The Ag-Mn oxide nanoparticles demonstrate excellent potential as a reliable visible-light-responsive photocatalyst for the efficient degradation of organic pollutants in wastewater treatment.

Bimetallic-based CuxCo3−xO4 nanoparticle-embedded N-doped reduced graphene oxide toward efficient oxygen evolution reaction and hydrogen evolution reaction for bifunctional catalysis

The fabrication of efficient electrocatalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is essential for hydrogen production to obtain sustainable renewable energy. Owing to the increase in chemical complexity, multimetallic catalysts provide flexibility to alter their electronic structure to attain high intrinsic catalytic activity via synergistic effects. In this study, bimetallic copper-cobalt oxide nanoparticles (CuxCo3−xO4 NPs) embedded on nitrogen-doped reduced graphene oxide (N-RGO) substrates are fabricated as catalysts for the OER and HER via a facile solution-hydrothermal synthesis. In the fabricated N-RGO-supported Cu-doped Co3-xO4 nanoparticle (CuxCo3−xO4 NPs@N-RGO) hybrid catalyst, the RGO sheet acts as a conductive network to promote electron transfer, thereby increasing the electrical conductivity of the catalyst. Additional active sites acting as bridged sites from the Cu and N dopants improve the catalytic activity, resulting in outstanding electrochemical activity for OER and HER. The optimal Cu0.35Co2.65O4 NPs@N-RGO catalyst exhibits an overpotential of 170 mV at 10 mA cm−2 for HER and a low overpotential of 270 mV for the OER in basic media, which are comparable to those of Pt/C and IrO2. The synthesized catalyst is a promising bifunctional catalyst for overall water splitting.

Exploration of polydopamine capped bimetallic oxide (CuO-NiO) nanoparticles inspired by mussels for enhanced and targeted paclitaxel delivery for synergistic breast cancer therapy

Integration of antitumor drug and metallic nanoparticles in a polymeric nanosystem with effective properties is an emerging and promising tool to improve tumor treatment. Nevertheless, there is still a clinical need for multifunctional nanoparticles (NPs) to be developed for an “all-in-one” platform with specific targeting, less side effects and high therapeutic efficacy. In this research, pH-responsive bimetallic oxide-multifunctional NPs wrapped by polydopamine polymer for simultaneous cancer cell targeting and drug delivery were synthesized based on simple metal nanoparticle-ligand interactions. We explored a unique nanosystem of mussel inspired, polydopamine complexed with copper/nickel oxide NPs (CuO-NiO@PDA NPs). CuO-NiO@PDA NPs were then loaded with anticancer drug paclitaxel (PTX) via electrostatic or π-π stacking interaction and functionalized with folic acid (FA), a tumor-targeting ligand, to form CuO-NiO@PDA-PTX/FA NPs. Results highlight therapeutic potential of CuO-NiO@PDA/FA NPs as paclitaxel delivery nanocarrier in breast cancer therapy with sustained drug release pattern due to their increased stability, biocompatibility and antitumor efficacy. Cell viability was demonstrated in vitro using AO/EB dual staining, and its anticancer potential was confirmed by a reactive oxygen species (ROS) assay and mitochondrial membrane potential staining experiments. Consequently, our designed CuO-NiO@PDA-PTX/FA NPs appear to be promising multipurpose nanocarriers with therapeutic potential for MCF-7 tumor targeting and penetration.

Antimicrobial and anticancer activities of biosynthesized bimetallic silver-zinc oxide nanoparticles (Ag-ZnO NPs) using pomegranate peel extract

AbstractIn the last two decades, nanomaterials have received much attention for the treatment of multidrug-resistant microbes that threaten human health. In the current study, the novelty and scientific significance concentrated on the biogenic synthesis of bimetallic silver-zinc oxide nanoparticles (Ag-ZnO NPs) using pomegranate peel extract (PPE) for the first time. The new constructed bimetallic Ag-ZnO NPs possessed the synergistic activity at a low concentration to avoid toxicity and elevate the superior potential. UV-Vis. characterization illustrated that Ag-ZnO NPs were small in size (15.8 nm), which was observed at 395.0 nm. The SEM image of Ag-ZnO NPs, incorporated with PPE, exhibited uniform Ag-ZnO NP surfaces with a clear surface appearance. It can be detected that Ag-ZnO NPs were isolated typically as a rounded particle across the PPE, which showed as brilliant NPs combined and stabilized with the prepared PPE. Results also revealed that Ag-ZnO NPs exhibited potential antibacterial activity toward Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, and Enterococcus faecalis where minimum inhibitory concentrations (MICs) were 62.5, 125, 15.62, 62.5, and 250 µg/ml. Likewise, Ag-ZnO NPs appeared antifungal activity against Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus, and Aspergillus brasiliensis, where MICs were 7.81, 31.25, 125, and 62.5 µg/ml, respectively. Moreover, Ag-ZnO NPs exhibited anticancer activities against MCF7 and Caco2, where IC50 was 104.9 and 52.4 µg/ml, respectively. Additionally, these concentrations are safe in use where results of cytotoxicity on Vero normal cell line confirmed that IC50 was 155.1 µg/ml. Overall, bimetallic Ag-ZnO NPs were for the first time, successfully biosynthesized using PPE; also, they had a promising antibacterial, antifungal, and anticancer activities.

Iron tolerant Bacillus badius mediated bimetallic magnetic iron oxide and gold nanoparticles as Doxorubicin carrier and for hyperthermia treatment

Among the different types of nanoparticles (NPs), iron oxide magnetic nanoparticles (IOMNPs) and bimetallic gold-magnetic iron oxide NPs (Au-IOMNPs) are gaining impetus for biomedical applications. Due to their unique properties such as super-paramagnetic behaviour, biocompatibility, and ease of surface modification, IOMNPs become suitable for drug delivery and hyperthermia applications. In this study, iron tolerant bacterium Bacillus badius was used in the optimized biogenic synthesis of gold NPs (AuNPs), IOMNPs, and bimetallic Au-IOMNPs and functionalized with doxorubicin (Dox). When analyzed by MTT assay, Dox functionalized Au-IOMNPs showed cytotoxicity against MCF7 cells line with an IC50 value of 147 μg/mL. Noteworthy, IOMNPs were found suitable for hyperthermia treatment as the temperature rise was up to 48 °C under an applied current of 400 Oe. Thus, this study demonstrated the application of Bacillus badius mediated IOMNPs and Au-IOMNPs for Dox delivery and hyperthermia treatment.

A facile and novel synthesis of bimetallic copper-manganese oxide nanoparticles anchored on carbon nanotubes

In the current contribution, copper-manganese bimetallic oxide nanoparticles attached to carbon nanotube surfaces have been created utilizing a straightforward method rather than complicated machinery. The employed sources of Cu and Mn were copper sulfate and potassium permanganate, which were combined with modified carbon nanotubes and thermally treated at 250, 350, and 450 °C, respectively. As the annealing temperature rises from 250 to 450 °C, the copper-manganese bimetallic oxide nanoparticles adhered to the surface of the carbon nanotubes gradually grow in size from 9 to 45 nm. XRD and FTIR methods were used to study structural characteristics. The existence of copper-manganese bimetallic oxide phases was established based on the results. The peak height and sharpness of the XRD data were also improved by increasing the annealing temperature, reflecting an improvement in the crystallinity. A broadband dielectric spectroscopy (BDS) was used to show how the applied frequency affected the dielectric characteristics.

Fabrication of Dye‐Sensitized Solar Cells Based on Novel Mixed Tungsten–Molybdenum and Tungsten–Titanium Oxides Nanoparticles Prepared by Impulse Underwater Plasma

Herein, a new method for synthesizing advanced nanocomposite materials based on tungsten, molybdenum, and titanium oxides by pulsed underwater plasma is reported. This is an environmentally friendly, energy‐saving, and simple method for obtaining bimetallic oxide nanoparticles with inhomogeneous defect structures. The chemical composition and morphology of the obtained particles are explored by electron microscopy and X‐ray diffraction spectroscopy. Four types of mixed‐oxide particles of tungsten–molybdenum and tungsten–titanium are synthesized and used to make the photoanodes for dye‐sensitized solar cells (DSSCs). The best DSSC shows a fill factor of 51% and a short‐circuit current density of 4.8 mA cm−2, resulting in a conversion efficiency of 4.11% and an improvement over the cells prepared from pure titanium or tungsten oxides.

BIOSSENSOR PARA NÍVEL DE INSULINA SANGUÍNEO EM ATLETAS

ABSTRACT Introduction: The pancreas releases insulin to assist the human body in utilizing blood glucose. It regulates metabolism by promoting the absorption of glucose into the blood. Objective: This work aimed to create an electrochemical biosensor based on magnetic graphene nanomaterial to measure insulin levels in athletes’ blood. Method: A magnetic graphene nanocomposite created by graphene oxide (GO) and Fe-Ni bimetallic oxides on a glassy carbon electrode was synthesized using the electrochemical deposition method (GCE). Results: The immediate electrical deposition of Fe-Ni bimetallic oxide nanoparticles with the spherical shape on the GO nanosheet without aggregations was validated by structural characterizations of Fe-Ni/GO/GCE using XRD and SEM. The electrochemical results for insulin determination showed good sensitivity and anti-interference capability. The applicability and accuracy of the proposed electrochemical sensor to detect insulin were explored by blood serum samples from sportsmen. Conclusion: The results assigned acceptable RSD values (3.31% to 4.30%) and confirmed the feasibility of the proposed sensor for detecting athletes’ blood insulin. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Calcination-controlled performance optimization of iron-vanadium bimetallic oxide nanoparticles for synergistic tumor therapy.

Calcination has been widely demonstrated as a favorable protocol for producing various inorganic nanomaterials for tumor therapy. However, little attention has been paid to its effect on the biotherapeutic efficacy of inorganic nanomaterials. Herein, we compare the effects of different calcination atmospheres on the therapeutic efficacy of Fe-V-O (FVO) nanomaterials. We find that compared with FVO nanomaterials synthesized by calcination in air, those prepared by argon calcination have a lower metallic valence state and a higher near-infrared light absorption capacity, hence resulting in significantly better biosafety and higher chemodynamic therapy (CDT)/photothermal therapy (PTT) efficacy. This study demonstrates that the therapeutic efficacy of inorganic nanomaterials can be optimized by employing different thermal treatment atmospheres, which provides new insights into the development of efficient anti-tumor agents.

Bimetallic oxide nanoparticles contained hollow spheres with sodium as a core: a promising energy storage advanced structure

The bimetallic oxide nanoparticles as outer shell with sodium entrapped as a core part of a hollow porous core–shell (HoPoCs) can be a promising battery electrode composition. Till now, scientists are struggling to synthesize ternary metal oxide hollow spheres due to the reactions between diverse cations and anions of different metal precursors. Also, the extremely reactive character of sodium prevents it from remaining alone without compound formation is unveiled. Here for the first time, we entrapped sodium and synthesized bimetallic nanoparticles contained outer shell hollowsphere (Na@ZnO@MoO2) successfully by sorption (absorption + adsorption) of two metal precursors (sodium molybdate dihydrate and zinc chloride) in two steps without adding any reaction inhibiting agent. As a result, significantly Na is entrapped as a core and ZnO and MoO2 nanoparticles forming the outer shell of the sphere. ‘Na’ entrapment is confirmed by X-ray photoelectron spectroscopy and high-angle annular dark-field scanning transmission electron microscopy elemental mapping. We employed our sodium entrapped HoPoCs bimetallic oxide nanoparticles sphere (Na@ZnO@MoO2) as a battery anode getting advantages from their structural specialty shows excellent battery properties promising for application in energy storage technologies. The initial specific capacity of these HoPoCs-Na@ZnO@MoO2 sphere is 940 mAh/g (1C), with exceptional stability (790 mAh/g) after 1000 cycles at a current density of 2C) and excellent rate capability. This approach will motivate the synthesis of other superior reactive element entrapped core–shell metal oxides for next-generation rechargeable batteries and other advanced suitable applications like microreactor, protector of explosive materials, and so on.