Magnetic Metal Nanoparticles Research Articles

Microfluidic Synthesis of Magnetic Nanoparticles for Biomedical Applications.

Magnetic nanoparticles have attracted great attention and become promising candidates in the biomedicine field due to their special physicochemical properties. They are generally divided into metallic and non-metallic magnetic nanoparticles, according to their compositions. Both of the two types have shown practical values in biomedicine applications, such as drug delivery, biosensing, bioimaging, and so on. Research efforts are devoted to the improvement of synthesis strategies to achieve magnetic nanoparticles with controllable morphology, diverse composition, active surface, or multiple functions. Taking high repeatability, programmable operation, precise fluid control, and simple device into account, the microfluidics system can expand the production scale and develop magnetic nanoparticles with desired features. This review will first describe different classifications of promising magnetic nanoparticles, followed by the advancements in microfluidic synthesis and the latest biomedical applications of these magnetic nanoparticles. In addition, the challenges and prospects of magnetic nanoparticles in the biomedical field are also discussed.

Magnetic bimetallic nanoparticles confined growth for enhancement of electromagnetic loss in void@Fe@SiO2/Co/C particles

The dispersion of diverse magnetic metallic in a single particle plays an important role in microwave absorption; however, its contribution is not clear due to the challenge of controllable synthesis of magnetic bimetallic nanoparticles in one micro/nanostructure. Herein, a series of magnetic bimetallic nanoparticles separately confined growth in a hollow multi-shell microsphere with proper impedance matching characteristic were prepared, which can be used as theoretical models to elucidate magnetic coupling effect between diverse magnetic metallic nanoparticles in a single particle on electromagnetic attenuation. The coupling effect of magnetic Co and Fe nanoparticles dispersed in different shell effectively enhance the microwave absorption performance of void@Fe@SiO2/Co/C particles with minimum reflection loss (RLmin) of −62.3 dB (RL=-20 dB, 99 % absorption) at a thickness of 2.05 mm, provoking the maximum radar cross-section (RCS) reduction value of perfect electric conductor (PEC) 37.37 dBm2. Meanwhile, broad effective bandwidth (EBW, RL≤-10 dB, ≥90 % absorption) response of 7.04 GHz at a thickness of 2.44 mm was achieved. These findings can provide guidance for the designation of novel magnetic broadband microwave absorbing materials (MAMs).

Synergistic Role of the AuAg-Fe3O4 Nanoenzyme for Ultrasensitive Immunoassay of Dengue Virus.

A combination of magnetic and noble metal nanoparticles (NPs) has recently emerged as a potential substance for rapid and sensitive immunosorbent assays. However, to make the assay an alternative method for Enzyme-linked immunosorbent assay, the individual role of each nanoparticle must be explored properly. In this work, an immunoassay has been proposed using two antibody-conjugated iron oxide nanoparticles (Fe3O4NPs) and gold-silver bimetallic nanoparticles (AuAgNPs) to enhance the sensitivity of virus detection by colorimetric TMB/H2O2 signal amplification. A synergistic effect is monitored between Fe3O4NPs and AuAgNPs, which is explored for colorimetric virus detection. The sensor exploits the synergistic effect between the nanoparticles to successfully detect a wide range of dengue virus-like particle (DENV-LP) concentrations ranging from 10 to 100 pg/mL with a detection limit of up to 2.6 fg/mL. In the presence of a target DENV-LP, a sandwich-like structure is formed, which restricts the electron transfer and the associated synergistic effect between the nanoparticles, restricting the TMB oxidation process. Therefore, the synergistic effect is the key to the present work, which accounts for the enhanced rate of the enzymatic reaction on TMB and makes the current method of virus detection more sensitive and reliable compared to the others.

Femtosecond laser writing of ant-inspired reconfigurable microbot collectives

Microbot collectives can cooperate to accomplish complex tasks that are difficult for a single individual. However, various force-induced microbot collectives maintained by weak magnetic, light, and electric fields still face challenges such as unstable connections, the need for a continuous external stimuli source, and imprecise individual control. Here, we construct magnetic and light-driven ant microbot collectives capable of reconfiguring multiple assembled architectures with robustness. This methodology utilizes a flexible two-photon polymerization strategy to fabricate microbots consisting of magnetic photoresist, hydrogel, and metal nanoparticles. Under the cooperation of magnetic and light fields, the microbots can reversibly and selectively assemble (e.g., 90° assembly and 180° assembly) into various morphologies. Moreover, we demonstrate the ability of assembled microbots to cross a one-body-length gap and their adaptive capability to move through a constriction and transport microcargo. Our strategy will broaden the abilities of clustered microbots, including gap traversal, micro-object manipulation, and drug delivery.

Single Particle Analysis-Enhanced DNA Walking Machine for Sensitive miRNA Detection.

DNA walking machines have achieved significant breakthroughs in areas such as biosensing, bioimaging, and early cancer diagnosis, facilitated by the self-assembly of DNA or its combination with other materials, such as magnetic beads and metal nanoparticles. However, current DNA walking machine strategies are constantly challenged by inadequate analytical sensitivity, while sophisticated signal amplification procedures are often indispensable. Single-particle inductively coupled plasma mass spectrometry (SP-ICPMS) provides superior sensitivity and can effectively discriminate between background noise and detected signals due to the large number of metal atoms in a nanoparticle and the concentrating effect of single nanoparticle detection. In this study, we present a novel approach utilizing single nanoparticle counting and duplex-specific nuclease (DSN)-assisted signal amplification to construct a 3D DNA walking machine for detecting the aggressive prostate cancer (PCa) biomarker miRNA-200c. The proposed strategy showed an improvement in sensitivity with a detection limit (LOD) of 0.93 pM (28 amol) and was successfully applied in human serum samples. To the best of our knowledge, this is the first report of the DNA walking machine with single nanoparticle counting study.

Activation of peroxymonosulfate with ZIF-67-derived Co/N-doped porous carbon nanocubes for the degradation of Congo red dye

In this study, porous carbon nanocubes encapsulated magnetic metallic Co nanoparticles (denoted as Co@N-PCNC) was prepared via pyrolyzing ZIF-67 nanocubes precursor at 600 °C and characterized by various technologies. It was used to activate peroxymonosulfate (PMS) to degrade Congo red (CR) dye efficiently. Over 98.45% of 50 mg L−1 CR was degraded using 0.033 mM PMS activated by 75 mg L−1 Co@N-PCNC within 12 min. The free radical quenching experiments were performed to reveal the nature of the reactive oxygen species radicals generated throughout the catalytic oxidation of CR. The effects of common inorganic anions and the water matrix on CR removal were studied. Moreover, the results of the kinetic study revealed the suitability of the pseudo-first-order and Langmuir–Hinshelwood kinetic models for illustrating CR degradation using the Co@N-PCNC/PMS system. Ultimately, the Co@N-PCNC displayed good operational stability, and after five cycles, the CR removal rate can still maintain over 90% after 12 min.

Pore-confined strategy to achieve controllable growth of Co/CoO in carbon nanofibers for the fabrication of lightweight and enhanced microwave absorbers

In recent years, magnetic metal nanoparticles (NPs)/carbon nanofibers (CNFs) composites have become very promising electromagnetic waves (EMWs) absorbers. However, how to achieve controllable growth of magnetic metals in CNFs is still an urgent problem to be solved. Herein, we reported a pore-confined strategy for constructing the porous Co/CoO/CNFs. By introducing different amounts of acetone (0.20 g, 0.30 g and 0.40 g) into the aqueous phase spinning solution to construct the porous structure, we achieved uniform distribution of Co/CoO NPs and ultimately obtained the porous Co/CoO/CNFs microwave absorbers (MAs) with excellent microwave absorption performance. Thanks to the excellent impedance matching and enhanced polarization loss, the porous Co/CoO/CNFs obtained the minimum reflection loss (RL) of −52.2 dB with a thickness of 3.0 mm, and the effective bandwidth (EBW) was 3.02 GHz when the acetone addition in the spinning solution was 0.30 g. Therefore, the pore-confined strategy proposed herein is conducive to the design of the MAs with excellent performance and low infilling rates based on CNFs. Furthermore, the porous structure of CNFs also improves the lightweight performance of the MAs.

Biosynthesized BiFe2O4@Ag nanoparticles mediated Scenedesmus obliquus induce apoptosis in AGS gastric cancer cell line

The use of magnetic metal nanoparticles has been considered in cancer treatment studies. In this study, BiFe2O4@Ag nanoparticles were synthesized biologically by Scenedesmus obliquus for the first time and their anticancer mechanism in a gastric cancer cell line was characterized. The physicochemical properties of the nanoparticles were evaluated by fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic Light Scattering (DLS), and zeta potential analyses. Cell viability and nuclear damage were investigated by the MTT and Hoechst staining assays, respectively. Flow cytometry analysis was performed to determine the frequency of the necrotic and apoptotic cells as well as cell cycle analysis of the nanoparticles-treated cells. Physicochemical characterization showed that the synthesized particles were spherical, without impurities, in a size range of 38–83 nm, with DLS size and zeta potential of 295.7 nm and -27.7 mV, respectively. BiFe2O4@Ag nanoparticles were considerably more toxic for the gastric cancer cells (AGS cell line) than HEK293 normal cells with IC50 of 67 and 117 µg/ml, respectively. Treatment of AGS cells with the nanoparticles led to a remarkable increase in the percentage of late apoptosis (38.5 folds) and cell necrosis (13.4 folds) and caused cell cycle arrest, mainly at the S phase. Also, nuclear fragmentation and apoptotic bodies were observed in the gastric cancer cells treated with the nanoparticles. This study represents BiFe2O4@Ag as a novel anticancer candidate against gastric cancer that can induce cell apoptosis through DNA damage and inhibition of cell cycle progression.

Silica coated MOFs-derived composites with excellent electromagnetic wave absorption and corrosion resistance

The microwave absorber with excellent corrosion resistance is an ideal layer for stealth applications in marine environments. Silica coated MOF-derived anti-corrosion absorbers were successfully fabricated by the Stöber method. The resulting powder demonstrated excellent performance not only in microwave absorption but also in corrosion resistance. The effective absorption bandwidth (EAB) of coated-12 reached 4.1 GHz and the minimum reflection loss (RLmin) came to −59.8 dB at 15.18 GHz in a 1.3 thickness with an 80 wt% filling ratio. The outstanding absorption performance is put down to the matched impedance and the various loss mechanism synergy. Besides, the electrochemical corrosion test revealed that the compact silica coating protected the inner corrodible magnetic metal nanoparticles from the outer corrosive environment. This work provides a reasonable and feasible method for synthesizing an excellent microwave absorber suitable for harsh environments.

Hydrazine metal complexes as a single source in the mechanochemical preparation of metallic magnetic nanoparticles and investigation of their magnetic hyperthermia properties

Ferromagnetic metallic cobalt and nickel nanoparticles were synthesized by intramolecular metal-hydrazine ligand oxidation reduction reaction in basic media and the solid state. Nickel nanoparticles Ni1 and Ni2 are obtained from two complexes, Ni(N2H4)2(C2O4) and Ni(N2H4)2(HCO2)2, respectively. X-ray powder diffraction (XRD) and energy-dispersive X-ray (EDX) data show pure fcc crystal structures of nanoparticles. Scanning electron microscopy (SEM) images revealed both Ni1 and Ni2 nanoparticles have agglomerated sphere morphologies. The crystallite size estimated by using the Scherer method for Ni1 and Ni2 were 18.7 and 6.2 nm. Vibrating sample magnetometer (VSM) data show the coercivity of metallic nickel samples Ni1 and Ni2 are 50 and 153 Oe, respectively. Both nanoparticles cause an increase in the temperature of water under applied alternative magnetic field and showed specific loss power (SLP) of 70 W/g and 104.8 W/g, respectively. The same method is used in preparation of cobalt nanoparticles from two complexes, Co(N2H4)2(C2O4) and Co(N2H4)2(HCO2)2. XRD analysis data show both nanoparticles have hcp crystal structure. SEM images show nanosheet structure with sheet thickness of 10 to 30 nm. Coercivity of Co1 and Co2 nanoparticles obtained by VSM and Hc are 182 and 171 Oe, respectively. In spite of high coercivity in both Co1 and Co2 nanoparticles, the magnetic hyperthermia heating effects are not observed in practice and specific loss power (SLP) is zero.

Investigating morphological, optical and magnetic properties of blended novel ZnO-Ag/NiFe2O4 nanocomposite

Metal oxide nanoparticles and magnetic nanoparticles are combined to create magnetic nanocomposites (MNCs) with unique physical, chemical, and biological properties. A new ZnO-Ag/NiFe2O4 ternary magnetic nanocomposite was created in the current study using a simple and straightforward solid-phase mixing process with subsequent thermal treatment. The structural, optical, and magnetic properties of the ZnO-Ag/NiFe2O4 nanocomposite were studied using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDAX), vibrating sample magnetometry (VSM), and Raman spectroscopy. Brunauer–Emmett–Teller (BET) analysis was performed to analyze the surface area and average pore diameter of the nanocomposite. Cyclic voltammetry and photoelectrochemical analysis were performed to study the electrical behavior and charge carrier concentrations. According to XRD studies, the ZnO-Ag/NiFe2O4 nanocomposite is composed of the hexagonal wurtzite of ZnO and the spinel cubic structure of NiFe2O4. FESEM analysis revealed that the crystals of the nanocomposite were nearly spherical, and EDAX elemental mapping indicated that the elements were evenly dispersed across the sample without any impurities. The average diameter of the ZnO-Ag/NiFe2O4 nanocomposite obtained from the TEM images was nearly 50.65 nm. The specific surface area and average pore diameter of the ZnO-Ag/NiFe2O4 nanocomposite were 13.58 m2/g and 4.33 nm, respectively, according to BET analysis. CV analysis revealed a sharp increase in the specific capacitance of the ZnO-Ag/NiFe2O4 nanocomposite. The specific capacitances of the 1 M NaOH electrolyte, ZnO nanoparticles and ZnO-Ag/NiFe2O4 nanocomposite were 55.7302 F/g, 53.947 F/g, and 87.229 F/g, respectively, at a 0.05 V/s scan rate. With a coercive field (Hc) of 167 Oe, remnant magnetization (Mr) of 0.73 emu/g, and saturation magnetization (Ms) of 6.58 emu/g, the blended magnetic nanocomposite ZnO-Ag/NiFe2O4 exhibited superparamagnetic behavior at ambient temperature. Using an external permanent magnet, the ZnO-Ag/NiFe2O4 nanocomposite may be extracted from the reaction mixture, indicating its probable environmental and biomedical application.

Magnetic Metallic Nanoparticles Coated with Carbon for the Catalytic Removal of Bromate from Water

Bromate, often detected in drinking water, is associated with a significant risk of cancer. Catalytic reduction has been recognized as an effective treatment technique to remove ions by reducing them over metal catalysts in the presence of a reducing agent, usually hydrogen. This work aims to synthesize metallic magnetic nanoparticles of iron oxide (FeO) and mixed iron oxides with manganese (MnFeO), cobalt (CoFeO), and copper (CuFeO) coated with carbon via chemical vapor deposition (C-MNP) to be applied as catalysts to the reduction of bromate in water. The use of magnetic nanoparticles coated with carbon enables catalyst recovery via magnetic separation and takes advantage of the catalytic properties of the carbon materials. The iron particles proved to be the most promising catalysts for the reduction of bromate into bromide, the highest removal being obtained with the CFeO@CVD750 sample, resulting in a 99% conversion after 120 min of reaction under the conditions tested. Due to its magnetic nature, the catalytic material was easily removed after the reaction and applied in four consecutive cycles without losing its catalytic properties. These results highlight the great potential of carbon-coated magnetic nanoparticles for reducing bromate in water.

Revolutionizing Imaging and Diagnostics: Harnessing Metallic Nanoparticles and Nanocarriers for Cutting-Edge Theranostics

The field of medical diagnostics and therapeutics is currently undergoing a transformative revolution, driven by the rapid advancements in nanotechnology. This paper explores the promising potential of metallic nanoparticles and nanocarriers in the realm of theranostics, a fusion of therapy and diagnostics, offering unprecedented opportunities for precision medicine and patient care. The integration of metallic nanoparticles and nanocarriers into medical applications has opened new frontiers for non-invasive imaging and targeted therapy. This review provides an in-depth analysis of metallic nanoparticles, including gold, silver, and magnetic nanoparticles, highlighting their unique physicochemical properties that make them ideal candidates for imaging and therapeutic purposes. Additionally, we discuss the evolution of nanocarriers, such as liposomes, micelles, and dendrimers, and their role in enhancing drug delivery, bioavailability, and treatment specificity. The versatility of metallic nanoparticles and nanocarriers in both imaging and therapeutic applications is showcased through their utilization in areas such as cancer diagnosis, drug delivery, and the management of neurological disorders. Furthermore, their potential to enable real-time monitoring of treatment responses and disease progression is explored, empowering clinicians with essential tools for personalized medicine. Challenges and considerations related to toxicity, biocompatibility, and regulatory hurdles are also discussed, shedding light on the need for further research and collaboration between scientists, clinicians, and regulatory bodies. As metallic nanoparticles and nanocarriers continue to evolve, they promise to revolutionize the landscape of medical diagnostics and therapy, ultimately improving patient outcomes and enhancing the effectiveness of healthcare practices. This paper serves as a comprehensive overview of the current state and future prospects of these groundbreaking technologies, contributing to the advancement of theranostics and its wide-reaching implications for the healthcare industry.

β‐Cyclodextrin‐Modified Cobalt Nanoparticles as 5‐Fluorouracil Carriers

AbstractMetal nanoparticles having magnetic properties are exciting for application in the directed transport of anticancer drugs encapsulated in them. To ensure drug‐loading capacity and controlled release, surface modification with host molecules is a fascinating choice. In this paper, we report the synthesis and surface modification of magnetic cobalt metal nanoparticles with oligosaccharide host molecules (β‐cyclodextrin) tethered on the surface. A β‐cyclodextrin‐folate derivative is synthesized and characterized using Infrared‐, Nuclear Magnetic Resonance‐, and Matrix‐Assisted Laser Deposition Ionization‐Time of Flight mass spectrometry. The size of the cobalt nanoparticles carrying the host molecule on the surface is ~10 nm. The nanoparticles are characterized using X‐Ray Diffraction, Transmission Electron Microscopy, particle size analyzer, Energy‐Dispersive X‐ray, and X‐ray Photoelectron Spectroscopy. The bare magnetic nanoparticles also show a strong saturation magnetization of 142.21 emu g−1. The chemotherapeutic drug 5‐fluorouracil is loaded on the surface‐modified cobalt nanoparticles through host: guest complexation mode and its controlled release is measured in‐vitro. The slow release is spread over more than 14 days, and a complete release of the loaded therapeutic cargo is not reached. The release is pH‐dependent and changes with acidic levels of the medium. The anticancer activity of the drug‐loaded nanocarrier on MDA‐MB‐231 (breast cancer) cells is investigated. The mechanism of cell death is studied, and the cells are found inhibited in the synthesis phase. Flow cytometric analysis shows that 79.70 % of the empty nanocarrier‐treated and 74.86 % 5‐fluorouracil‐loaded nanocarrier‐treated MDA‐MB‐231 cells were in the early apoptosis phase. This new combination nanocarrier is intriguing owing to its structural and magnetic properties, and the action on cell lines.

Research progress in the detection of common foodborne hazardous substances based on functional nucleic acids biosensors.

With the further improvement of food safety requirements, the development of fast, highly sensitive, and portable methods for the determination of foodborne hazardous substances has become a new trend in the food industry. In recent years, biosensors and platforms based on functional nucleic acids, along with a range of signal amplification devices and methods, have been established to enable rapid and sensitive determination of specific substances in samples, opening up a new avenue of analysis and detection. In this paper, functional nucleic acid types including aptamers, deoxyribozymes, and G-quadruplexes which are commonly used in the detection of food source pollutants are introduced. Signal amplification elements include quantum dots, noble metal nanoparticles, magnetic nanoparticles, DNA walkers, and DNA logic gates. Signal amplification technologies including nucleic acid isothermal amplification, hybridization chain reaction, catalytic hairpin assembly, biological barcodes, and microfluidic system are combined with functional nucleic acids sensors and applied to the detection of many foodborne hazardous substances, such as foodborne pathogens, mycotoxins, residual antibiotics, residual pesticides, industrial pollutants, heavy metals, and allergens. Finally, the potential opportunities and broad prospects of functional nucleic acids biosensors in the field of food analysis are discussed.

Electrospinning of bitter gourd shape CoNiSe2@N carbon nanofibers as absorbers for electromagnetic wave attenuation

Among all designated microwave absorbers, the combination of magnetic metal with carbon nanomaterials has been considered as one of the most effective ways for the absorption of electromagnetic wave (EMW). The incorporation of doped magnetic metal nanoparticles (NPs) with carbon nanomaterials provides excellent magnetic loss. Additionally, carbon matrix possesses tunable dielectric properties and designable microstructure which could further improving the performance of the EMW absorption. Herein, N-doped carbon nanofibers doped with CoNiSe2 NPs was fabricated by electrospinning, carbonization and selenization process using for the EMW absorbers. The lowest reflection loss (RL) of −47.7 dB at the thickness of 2.1 mm while an effective absorption bandwidth (EAB) of 7.12 GHz at the thickness of 2.4 mm was achieved. The enhanced EMW attenuating properties can be attributed to the multiple EMW reflections, interfacial polarization between the fibers and magnetic loss facilitated by CoNiSe2 NPs. This work provides a promising strategy for introducing multiple components to improve the EMW absorbing properties and can be potentially extended to the fabrication of other functional anti-electromagnetic materials.

3D spatially-confined magnetic anodes towards advanced lithium ion batteries

Magnetic transition-metal oxides show great prospect as alternatives to prevail anodic carbonaceous substances for lithium ion battery in virtue of their splendid theoretical capacity. However, in addition to their intrinsic poor electronic conductivity, the severe agglomeration of the forming magnetic metal nanoparticles during discharging will deteriorate their actual electrochemical performance in a strong magnetic field environment. Here, we demonstrate a 3D spatially-confining magnetic anode to settle all these dilemmas, in which conversion-type magnetic Fe3O4 nanoparticles with a thin carbon encapsulation layer are anchoring onto 3D nickel nanotube arrays skeleton (Ni/Fe3O4@C NTAs). The carbon shell spatially confines the agglomeration of Fe nanoparticles and maintains the exceptional integrity of structure. The Ni/Fe3O4@C NTAs anode exhibits high-capacity lithium storage (∼1286 mAh g−1 at 0.1 C) and superior rate/cycle capability (retaining ∼97 % of initial reversible value at 1 C after long-term 1000 cycles).

Antidiabetic and antioxidant effect of magnetic and noble metal nanoparticles of Clitoria ternatea

Diabetes is a chronic metabolic endocrine disorder associated with diabetic complications that result in microvascular and macrovascular complications due to oxidative stress, neurodegeneration, and peripheral cell damage. Oxidative stress is characterized by the development of reactive oxygen species (ROS) which progresses by hampering antioxidant enzyme activities. Phytomolecules from different plant sources like leaves, flowers, fruits, etc are reported to possess super-antioxidant properties. Hence these phytomolecules can be good leads in the treatment and management of diabetes. Metal nanoparticles have evolved to increase the potency, efficacy, and safety of different drug delivery systems owing to their superior physicochemical properties. This research work is designed for the synthesis of magnetic and noble metal nanoparticles by green synthesis of fresh flower aqueous extract of Clitoria ternatea. A mechanistic evaluation of the magnetic (cobalt oxide) and noble metal (gold) nanoparticles has been designed by in-vitro and in-vivo models of a streptozotocin-induced diabetes model. The cobalt oxide and gold nanoparticles showed a significant (p < 0.05) decrease in the diabetic enzyme levels (α-amylase, α-glucosidase, and xanthine oxidase). In vitro and in vivo studies of the antioxidant activity of both nanoparticles also revealed the increased potential of antioxidant activity. In-vivo studies of both nanoparticles exhibited anti-diabetic properties by significantly enhancing the level of insulin. The cholesterol profiling of both nanoparticles proved the reduction of levels of serum cholesterol, triglycerides, HDL, VLDL, LDL, and creatinine content signifying the decreasing risk of macrovascular complications associated with diabetes. However, gold nanoparticles produced a more protective effect as compared to cobalt oxide nanoparticles. The study concludes that the magnetic and gold nanoparticles conjugated with Clitoria ternatea exhibited potential anti-diabetic and antioxidant activities in a streptozotocin-induced diabetic rat model.

Topological MOFs deformation for the direct preparation of electromagnetic functionalized Ni/C aerogels with good hydrophobicity and thermal insulation

Magnetic carbon-based aerogels are nowadays a kind of emerging candidates for high-performance electromagnetic wave absorbing materials (EWAMs), because their unique structural advantages lay a good foundation for the propagation and attenuation of electromagnetic (EM) wave. However, traditional post-treatment methods for magnetic carbon-based aerogels often face difficulties in maintaining aerogel structure, regulating the content of magnetic components, and dispersing magnetic particles. Herein, we first induce a topological deformation of bulky Ni-MOF particles to generate Ni-MOF aerogel assembled by crosslinked fibers, and then convert this intermediate aerogel to final Ni/C composite aerogels (NCCAs) through controllable high-temperature pyrolysis. This novel strategy achieves high loading and uniform dispersion of magnetic metal nanoparticles throughout carbon skeleton. Pyrolysis temperature plays a very important role to determine the overall attenuation capability and impedance matching of NCCAs, because it has a remarkable impact on the dielectric loss of carbon skeleton but negligible effect on magnetic loss. When the temperature is 700 °C, the optimum product (NCCA-2) will show the best EM absorption performance among this series of composites, including strong reflection loss and broad effective absorption bandwidth. Surprisingly, the integrated advantages of aerogel structure and MOFs transformation not only render NCCA-2 as a highly competitive candidate for high-performance EWAMs as compared with various Ni/C composites, but also bestow it on excellent hydrophobic and thermal insulation properties.

Inorganic Nanomaterials Used in Anti-Cancer Therapies:Further Developments

In this article, we provide an overview of the progress of scientists working to improve the quality of life of cancer patients. Among the known methods, cancer treatment methods focusing on the synergistic action of nanoparticles and nanocomposites have been proposed and described. The application of composite systems will allow precise delivery of therapeutic agents to cancer cells without systemic toxicity. The nanosystems described could be used as a high-efficiency photothermal therapy system by exploiting the properties of the individual nanoparticle components, including their magnetic, photothermal, complex, and bioactive properties. By combining the advantages of the individual components, it is possible to obtain a product that would be effective in cancer treatment. The use of nanomaterials to produce both drug carriers and those active substances with a direct anti-cancer effect has been extensively discussed. In this section, attention is paid to metallic nanoparticles, metal oxides, magnetic nanoparticles, and others. The use of complex compounds in biomedicine is also described. A group of compounds showing significant potential in anti-cancer therapies are natural compounds, which have also been discussed.