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It is well known the capacity of potassium ferrate (Fe(VI)) for the oxidation of pollutants or co-precipitation and adsorption of hazardous species. However, little information has been paid on the adsorption and co-precipitation contribution of the Fe(VI) resultant nanoparticles, the in situ hydrolytic ferric iron oxides. Here, the removal of arsenate (As(V)) and arsenite (As(III)) by Fe(VI) was investigated, which focused on the interaction mechanisms of Fe(VI) with arsenic, especially in the contribution of the co-precipitation and adsorption of its hydrolytic ferric iron oxides. pH and Fe(VI) played significant roles on arsenic removal; over 97.8% and 98.1% of As(V) and As(III) removal were observed when Fe(VI):As(V) and Fe(VI):As(III) were 24:1 and 16:1 at pH 4, respectively. The removal of As(V) and As(III) by in situ and ex situ formed hydrolytic ferric iron oxides was examined respectively. The results revealed that As(III) was oxidized by Fe(VI) to As(V), and then was removed though co-precipitation and adsorption by the hydrolytic ferric iron oxides with the contribution content was about 1:3. For As(V), it could be removed directly by the in situ formed particles from Fe(VI) through co-precipitation and adsorption with the contribution content was about 1:1.5. By comparison, As(III) and As(V) were mainly removed through adsorption by the 30-min hydrolytic ferric iron oxides during the ex situ process. The hydrolytic ferric iron oxides size was obviously different in the process of in situ and ex situ, possessing abundant and multiple morphological structures ferric oxides, which was conducive for the efficient removal of arsenic. This study would provide a new perspective for understanding the potential of Fe(VI) treatment on arsenic control., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In this critical review, we outline various covalent and non-covalent approaches for the functionalization of iron oxide nanoparticles (IONPs). Tuning the surface chemistry and design of magnetic nanoparticles are described in relation to their applicability in advanced medical technologies and biotechnologies including magnetic resonance imaging (MRI) contrast agents, targeted drug delivery, magnetic separations and immobilizations of proteins, enzymes, antibodies, targeting agents and other biosubstances. We review synthetic strategies for the controlled preparation of IONPs modified with frequently used functional groups including amine, carboxyl and hydroxyl groups as well as the preparation of IONPs functionalized with other species, e.g., epoxy, thiol, alkane, azide, and alkyne groups. Three main coupling strategies for linking IONPs with active agents are presented: (i) chemical modification of amine groups on the surface of IONPs, (ii) chemical modification of bioactive substances (e.g. with fluorescent dyes), and (iii) the activation of carboxyl groups mainly for enzyme immobilization. Applications for drug delivery using click chemistry linking or biodegradable bonds are compared to non-covalent methods based on polymer modified condensed magnetic nanoclusters. Among many challenges, we highlight the specific surface engineering allowing both therapeutic and diagnostic applications (theranostics) of IONPs and magnetic/metallic hybrid nanostructures possessing a huge potential in biocatalysis, green chemistry, magnetic bioseparations and bioimaging., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The research of nanomaterials for bio-imaging and theranostic are very active nowadays with unprecedented advantages in nanomedicine. Homologous targeting and bio-imaging greatly improve the ability of targeted drug delivery and enhance active targeting and treatment ability of nanomedicine for the tumor. In this work, lycorine hydrochloride (LH) and magnetic iron oxide nanoparticles coated with a colorectal cancer (CRC) cell membrane (LH-Fe 3 O 4 @M) were prepared, for homologous targeting, magnetic resonance imaging (MRI), and chemotherapy. Results showed that the LH-Fe 3 O 4 @M and Fe 3 O 4 @M intensity at HT29 tumor was significantly higher than that Fe 3 O 4 @PEG, proving the superior selectivity of cancer cell membrane-camouflaged nanomedicine for homologous tumors and the MRI effect of darkening contrast enhancement were remarkable at HT29 tumor. The LH-Fe 3 O 4 @M exhibited excellent chemotherapy effect in CRC models as well as LH alone and achieved a high tumor ablation rate but no damage to normal tissues and cells. Therefore, our biomimetic system achieved a homologous targeting, bio-imaging, and efficient therapeutic effect of CRC., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

When developing new nanoparticles for bio-applications, it is important to fully characterize the nanoparticle's behavior in biological systems. The most common techniques employed for mapping nanoparticles inside cells include transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). These techniques entail passing an electron beam through a thin specimen. STEM or TEM imaging is often used for the detection of nanoparticles inside cellular organelles. However, lengthy sample preparation is required (i.e., fixation, dehydration, drying, resin embedding, and cutting). In the present work, a new matrix (FTO glass) for biological samples was used and characterized by field emission scanning electron microscopy (FE-SEM) to generate images comparable to those obtained by TEM. Using FE-SEM, nanoparticle images were acquired inside endo/lysosomes without disruption of the cellular shape. Furthermore, the initial steps of nanoparticle incorporation into the cells were captured. In addition, the conductive FTO glass endowed the sample with high stability under the required accelerating voltage. Owing to these features of the sample, further analyses could be performed (material contrast and energy-dispersive X-ray spectroscopy (EDS)), which confirmed the presence of nanoparticles inside the cells. The results showed that FE-SEM can enable detailed characterization of nanoparticles in endosomes without the need for contrast staining or metal coating of the sample. Images showing the intracellular distribution of nanoparticles together with cellular morphology can give important information on the biocompatibility and demonstrate the potential of nanoparticle utilization in medicine., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Hepatocellular carcinoma (HCC) has a significant economic impact and a high mortality rate. Telmisartan (TLM) is a potential therapy for HCC, but it has a limited scope in drug delivery due to unpredictable distribution and poor bioavailability. The objective of this study was to prepare, design, and in vitro evaluate lactose-modified chitosan nanoparticles (LCH NPs) as a liver-targeted nanocarrier for TLM with the potential to offer a promising HCC therapy. The combination of chitosan with lactose was successfully attained using the Maillard reaction. TLM-LCH NPs were prepared, characterized, and optimized with the developed 2 3 full factorial design. The optimized formulation (F1) was in vitro and in vivo characterized. LCH was synthesized with an acceptable yield of 43.8 ± 0.56%, a lactosylation degree of 14.34%, and a significantly higher aqueous solubility (6.28 ± 0.21 g/L) compared to native chitosan (0.25 ± 0.03 g/L). In vitro characterization demonstrated that, F1 had a particle size of 145.46 ± 0.7 nm, an entrapment efficiency of 90.21 ± 0.28%, and a surface charge of + 27.13 ± 0.21 mV. In vitro TLM release from F1 was most consistent with the Higuchi model and demonstrated significantly higher release at pH 5.5. Moreover, a significantly higher ratio of liver to plasma concentration was observed with TLM-LCH NPs compared to plain TLM and unmodified TLM-NPs. The obtained results nominate TLM-LCH NPs as a promising carrier for enhancing liver targeting of TLM in treatment of HCC., (© 2023. The Author(s).)

A novel core-shell nanomaterial based on prussian blue (PB) coating on peculiar surface active maghemite nanoparticles (SAMNs), was developed. The synthetic process involves the direct crystallization of Fe(II)(CN)6(4-) onto the surface of SAMNs by simple incubation in water at controlled pH, demonstrating the presence of under-coordinated Fe(III) on nanoparticle surface. The coating reaction occurs in a narrow pH range and the synthetic procedure was optimized. The resulting SAMN@PB hybrid nanostructures were characterized by transmission and scanning electron microscopy, Mössbauer, UV-vis and FTIR spectroscopy and X-ray powder diffraction. The nanomaterial, characterized by high stability in alkaline media, behave as excellent electro-catalyst for hydrogen peroxide reduction. The stability of SAMN@PB hybrid has been investigated as a function of pH, showing excellent stability up to pH 9.0 and demonstrating the feasibility of SAMNs, superficially derivatized with prussian blue, to produce an efficient and extremely stable nanostructured material. This maghemite supported nanostructured prussian blue was applied to develop a sensor, based on a simple carbon paste electrode, which was able to catalyze the electro-reduction of hydrogen peroxide, in aqueous solutions, buffered at pH 7.0, at low applied potentials (0.0 V vs. SCE)., (© 2013 Elsevier B.V. All rights reserved.)

Nanoscale zero-valent iron (nZVI) particles and a composite containing a mixture of ferrate(VI) and ferrate(III) were prepared by thermal procedures. The phase compositions, valence states of iron, and particle sizes of iron-bearing compounds were determined by combination of X-ray powder diffraction, Mössbauer spectroscopy and scanning electron microscopy. The applicability of these environmentally friendly iron based materials in treatment of chemical warfare agents (CWAs) has been tested with three representative compounds, sulfur mustard (bis(2-chlorethyl) sulfide, HD), soman ((3,3'-imethylbutan-2-yl)-methylphosphonofluoridate, GD), and O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothiolate (VX). Zero-valent iron, even in the nanodimensional state, had a sluggish reactivity with CWAs, which was also observed in low degrees of CWAs degradation. On the contrary, ferrate(VI)/(III) composite exhibited a high reactivity and complete degradations of CWAs were accomplished. Under the studied conditions, the estimated first-order rate constants (≈ 10(-2)s(-1)) with the ferrate(VI)/(III) composite were several orders of magnitude higher than those of spontaneous hydrolysis of CWAs (10(-8)-10(-6)s(-1)). The results demonstrated that the oxidative technology based on application of ferrate(VI) is very promising to decontaminate CWAs., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Nanoparticles (NPs) have gained more attention as drug delivery systems. Folic acid (FA)-chitosan (CS) conjugates, because of their biodegradability, low toxicity, and better stability, offer a pharmaceutical drug delivery tool. The aim of this work was to fabricate CuS NPs modified by CS followed by grafting FA as a nanocarrier for the delivery of cytarabine (CYT) as an anticancer drug. In this work, CuS NPs modified by CS and FA were successfully synthesized. The structural properties of the nanocarrier were characterized by using scanning electron microscopy, Fourier transform infrared, X-ray diffraction, thermogravimetric analysis, and Brunauer-Emmett-Teller. The adsorption mechanism of CYT by adsorption isotherms, kinetics, and thermodynamics was deliberated and modeled. The in vitro CYT release behavior for the nanocarrier was 99% and 61% at pH 5.6 and 7.4, respectively. The adsorption behavior of CYT by CuS NP s -CS-FA was well explored by pseudo-second-order kinetic and Langmuir isotherm models by the coefficient of determination (R 2 > 0.99). Thermodynamic results showed that the uptake of CYT by CuS NPs-CS-FA was endothermic and spontaneous. The experimental results showed that CYT/CuS NP s -CS-FA can be proposed as an efficient nanocarrier for the targeted delivery of anticancer drugs., (© 2022 International Union of Biochemistry and Molecular Biology, Inc.)

Nanoscale zero-valent iron particles (NZVI) are widely used in a variety of industries owing to their advantageous mechanical, physical, and chemical properties. These particles can be released into environmental media, including water, soil, and air, through several pathways. NZVI in the ecosystem can be taken up, excreted and distributed within organisms, which is harmful to plants, animals and humans. Plants play a significant role as producers in the ecological circle and can both positively and negatively affect the ecological behavior of NZVI. Therefore, understanding the relationship between plants and NZVI is likely to be of great value for the assessment of NZVI-associated risks and future research directions. In this review, we summarize the current knowledge on the uptake, distribution, and accumulation of NZVI in plants; the phytotoxicity triggered by NZVI exposure at the physiological, biochemical, and molecular levels; and the defense mechanism used by plants to defend against NZVI-induced insults. We further discuss the toxic effects of NZVI on soil animals and microorganisms as well as the risk posed by the presence of NZVI in the food chain., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

In recent times, magnesium oxide (MgO) nanoparticles are proven to be an excellent antibacterial agent which inhibits the growth of bacteria by generating reactive oxygen species (ROS). Release of ROS by nanoparticles will damage the cell membrane of bacteria and leads to the leakage of bacterial internal components and cell death. However, chemically synthesized MgO nanoparticles may possess toxic functional groups which may inhibit healthy human cells along with bacterial cells. Thus, the aim of the present study is to synthesize MgO nanoparticles using leaf extracts of Amaranthus tricolor and photo-irradiation of visible light as a catalyst, without addition of any chemicals. Optimization was performed using Box-Behnken design (BBD) to obtain the optimum condition required to synthesize smallest nanoparticles. The parameters such as time of reaction, the concentration of precursor, and light intensity have been identified to affect the size of biosynthesized nanoparticles and was optimized. The experiment performed with optimized conditions such as 0.001 M concentration of magnesium acetate as precursor, 5 cm distance of light (intensity), and 15 min of reaction time (light exposure) has led to the formation of 74.6 nm sized MgO nanoparticles. The antibacterial activities of MgO nanoparticles formed via photo-irradiation and conventional biosynthesis approach were investigated and compared. The lethal dosage of E. coli for photo-irradiated and conventional biosynthesis MgO nanoparticles was 0.6 ml and 0.4 ml, respectively. Likewise, the lethal dosage of S. aureus for both biosynthesis approaches was found to be 0.4 ml. The results revealed that the antibacterial activity of MgO nanoparticles from both biosynthesis approaches was similar. Thus, photo-irradiated MgO nanoparticles were beneficial over heat-mediated conventional method due to the reduced synthesis duration.

Food safety is a priority issue for sustainable global development that can be affected by heavy metals, contributing to morbidity and even mortality in crop growth. Heavy metals often accumulate in the soil due to the use of extensive chemical fertilizers and pesticides; therefore, the current experiment was aimed to determine the effect of glutamate zerovalent iron nanoparticles (Glu-ZVFeNPs) and indole acetic acid (IAA) on physiological mechanism of lead (Pb +2 ) stress tolerance at 4 and 8 ppm in Zea mays variety. Seeds of the selected variety were collected from Cereal Crop Research Institute Persabaq Nowshera and planted in earthen pots in triplicate in the greenhouse of the Botany Department of the University of Peshawar. Nanoparticles were analyzed via scanning electron microscopy and energy dispersive X-ray analysis. Maximum growth responses were recorded from T12 (untreated + NPs + IAA), while minimum were recorded from T5 (8 ppm) indicating from the minimum amplitude of chlorophyll "a" and "b" contents, root length, shoot length, and root/shoot ratio. T5 (8 ppm) enhanced the values of osmolytes and antioxidant enzymes peroxidase and superoxide dismutase which has been ameliorated by the combined application of Glu-ZVFeNPs + IAA, indicating that the plant may resist the toxic effects of heavy metal stress at high concentration. From the present study, we concluded that adverse result of Pb +2 has been condensed by application of Glu-ZVFeNPs + IAA treatment as compared to the foliar application of IAA and Glu-ZVFeNPs individually., (© 2020 Wiley Periodicals LLC.)

Composites of iron oxide nanoparticles immobilized on the surface of various clay mineral matrices (muscovite, montmorillonite and vermiculite) have been prepared by the alkaline oxidative hydrolysis of iron sulphate in the presence of mineral matrices. The composites have been studied by Mössbauer spectroscopy, XRD, TEM and SQUID. Correspondence between the hyperfine parameters and the iron oxide particle size and magnetic behaviour has been proved. The prepared composites differ in magnetic properties, size and morphology of the iron oxide particles. [ABSTRACT FROM AUTHOR]

This review highlights potential application areas for carbon-based molecular nanoparticles, such as carbon dots, carbon nanotubes, graphene quantum dots, and carbon quantum dots. The success of nanomanufacturing hinges on robust collaboration between academia and industry to advance applicable manufacturing techniques. Choosing the right approach is crucial, one that integrates the carbon base of nanomaterials with the required properties and impurities, as well as the scalability of the process. Molecular, in this context, refers to the nanoscale carbon structures that form the basis of these materials, including their arrangement, bonding, and properties at the molecular level. The article also explores the characterization of different types of molecular nanomaterials. Nanomaterials are increasingly used in almost every contemporary industry, including construction, textiles, manufacturing, and computing. This article reviews the most prominent sectors globally that employ nanomaterials. Biomasses containing lignin, cellulose, and hemicellulose have become some of the most extensively studied. Initially, rice waste was utilized for bulk materials, but lately, the production of multifunctional materials has surged in interest. Carbon nanostructures derived from rice waste offer a broad spectrum of applications and enhanced biocompatibility. Recent advancements, challenges, and trends in the development of multifunctional carbon-based nanomaterials from renewable rice waste resources are considered. [ABSTRACT FROM AUTHOR]

In recent years, significant progress has been made in the subject of nanotechnology, with a range of methods developed to synthesize precise-sized and shaped nanoparticles according to particular requirements. Often, the nanoparticles are created by employing dangerous reducing chemicals to reduce metal ions into uncharged nanoparticles. Green synthesis or biological approaches have been used recently to circumvent this issue because biological techniques are simple, inexpensive, safe, clean, and extremely productive. Nowadays, much research is being conducted on how different kinds of nanoparticles connect to proteins and nucleic acids using molecular docking models. Therefore, this review discusses the most recent advancements in molecular docking capacity to predict the interactions between various nanoparticles (NPs), such as ZnO, CuO, Ag, Au, and Fe3O4, and biological macromolecules. [ABSTRACT FROM AUTHOR]

Magnetic nanofluids, also referred to as ferromagnetic particle levitation systems, are materials with highly responsive magnetic properties. Due to their magnetic responsiveness, excellent controllability, favorable thermal characteristics, and versatility, magnetic nanofluids have sparked considerable interest in both industrial manufacturing and scientific research. Magnetic nanofluids have been used and developed in diverse areas such as materials science, physics, chemistry and engineering due to their remarkable characteristics such as rapid magnetic reaction, elastic flow capacities, and tunable thermal and optical properties. This paper provides a full and in-depth introduction to the diverse uses of ferrofluids including material fabrication, fluid droplet manipulation, and biomedicine for the power and machinery sectors. As a result, magnetic nanofluids have shown promising applications and have provided innovative ideas for multidisciplinary research in biology, chemistry, physics and materials science. This paper also presents an overview of the device construction and the latest developments in magnetic-nanofluid-related equipment, as well as possible challenging issues and promising future scenarios. [ABSTRACT FROM AUTHOR]

Background: There is a continuous growth of interest in the development of nano-drug delivery systems that could combine therapy and diagnosis of cancer. Results: Novel multifunctional superparamagnetic iron oxide nanoparticles (SPIONs, chemically Fe3O4) conjugated with carboxymethyl sagocellulose (CMSC), and 5-fluorouracil (Fe3O4-CMSC-5FU) were synthesized. The conjugated nanoparticles have the magnetic properties of the SPIONs, which allows the nanoparticles to be localized at the target area by applying an external magnetic field. SPIONs generate heat upon exposure to laser lights, resulting in a photothermic effect. The drug-loading efficiency of 5-FU into the SPIONs-CMSC conjugated nanoparticles was 70 to 84% w/w which could release the drug at intracellular pH (5.4) of cancer cells and resist drug release at pH 7.2. In vivo studies using mice models confirmed the nanoparticles could efficiently deliver 5-FU only to the cancer cells and the anticancer effect was enhanced by laser-induced hyperthermia. Conclusions: The combination of targeted delivery of 5-FU with photothermal therapy (PTT) looks promising for selective killing of cancer cells. Furthermore, SPIONs are an excellent contrasting agent for use in computerized tomography (CT) imaging for determining the tumor location and monitoring the progress of the therapy. The focus of this work was the oncological application of multifunctional Fe3O4-CMSC-5FU nanoparticle conjugates, with an emphasis on therapeutic, diagnostic and prognostic purposes. [ABSTRACT FROM AUTHOR]

The biosynthesis technique and biogenic copper oxide nanoparticles (CuONPs) are commonly used in a variety of applications including medicine. Bare (CuONPs) and boron-doped copper oxide nanoparticles (B/CuONPs) were produced via the green synthesis method using Thymbra spicat ssp. spicata due to their nontoxic, coast effective and facile properties. The nanoparticles were characterized by using X-ray diffraction, fourier transform infrared, UV–visible spectroscopy, transmission electron microscopy, and Scanning electron microscopy with Energy Dispersive X-ray spectroscopy analysis. The produced nanoparticles performed antibacterial activity against human pathogenic organisms of both Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria by using the microdilution technique. B/CuONPs showed high activity on Gram-positive bacteria, while CuONPs showed high activity on Gram-negative bacteria. The cytotoxic effect synthesized CuONPs and B/CuONPs were evaluated against human hepatocarcinoma (HepG2) cells by using MTT, Annexin-V, Caspase-3/7, and confocal microscopic evaluations. Moreover, the in-silico results have shown for the first time that the active role in the Caspase-3/7 step of the triggered apoptosis pathway is due to the activity of Caspase-7. The results indicated that the biogenic CuONPs and B/CuONPs exerted potential anti-cancer and anti-bacterial activity on HepG2 and S. aureus and E. coli that imply to remarkable biological activity. The green synthesized nanoparticles have clearly proposed promising biogenic nanomaterials for biomedical treatments. [ABSTRACT FROM AUTHOR]

In this study, we investigated the removal of hexavalent chromium (Cr(VI)) through an innovative approach, which employed iron sulfide nanoparticles synthesized via a green chemistry technique, utilizing extracts derived from date palm seeds (referred to as ds-FeS). Batch studies, which were well represented by the Langmuir isotherm model, were conducted to determine the maximum removal capacities (qm) of ds-FeS nanoparticles at three different initial pH conditions (pH = 3, 7, and 9). Additionally, batch kinetic studies were conducted under varying conditions of initial Cr(VI) load (3.5, 9, 27, and 38 mg/g of nanoparticles), nanoparticle dose (25, 37, 50, and 75 g/g of Cr(VI)), and initial pH (3, 5, 7, and 9). Results demonstrated the positive impact of acidic pH during Cr(VI) removal by ds-FeS wherein the highest qm of 31.3 mg/g and initial rate of 6.95 mg/g·min (pseudo-second order kinetics) were observed at pH 3. Conversely, with an increase in pH to neutral and alkaline conditions, a decline in both qm and initial rates was observed. Measurements of solution pH, total chromium, and particle surface chemistry using X-ray diffraction and Fourier transform infrared spectrometry techniques revealed the crucial roles of reduction, surface precipitation, and complexation processes in Cr(VI) removal by ds-FeS nanoparticles. Overall, this study demonstrates the promising potential of environmentally friendly, date palm seed–derived iron sulfide nanoparticles for Cr(VI) removal. [ABSTRACT FROM AUTHOR]

The mononuclear ruthenium 1-Cl and dinuclear ruthenium 2-Cl complexes undergo a photo-induced ligand exchange in water, affording the corresponding 1-H2O and 2-H2O complexes. The use of indium tin oxide nanoparticles (nanoITOs) to explore the photo-electrochemistry of the in situ-generated 1-H2O and 2-H2O in solution revealed greater photocurrents produced by these two complexes when compared with an experiment using a buffer only. Interestingly, the high photocurrent shown by the dinuclear complex 2-H2O was accompanied by the deposition of its higher oxidation state (H2O)RuII–RuIII(OH), as evidenced with cyclic voltammetry, SEM and XPS. The IPCE and spectro-electrochemistry studies supported by TD-DFT calculations revealed the visible light harvesting ability of 1-H2O and 2-H2O in solution and the subsequent electron injection into the conduction band of the nanoITOs, enhanced in 2-H2O via a plausible chelating effect. [ABSTRACT FROM AUTHOR]

Background: Oxides of lanthanide rare-earth elements show great potential in the fields of imaging and therapeutics due to their unique electrical, optical and magnetic properties. Oxides of lanthanide-based nanoparticles enable high-resolution imaging of biological tissues by magnetic resonance imaging (MRI), computed tomography (CT) imaging, and fluorescence imaging. In addition, they can be used to detect, treat, and regulate diseases by fine-tuning their structure and function. It remains challenging to achieve safer, efficient, and more sensitive nanoparticles for clinical applications through the structural design of functional and nanostructured rare-earth materials. Result: In this study, we designed a mesoporous silica-coated core–shell structure of europium oxide ions to obtain near-infrared two-photon excitation fluorescence while maintaining high contrast and resolution in MRI. We designed enhanced 800 nm photoexcitation nanostructures, which were simulated by the finite-difference method (FDM) and finite-difference time-domain method (FDTD). The nanoparticle structure, two-photon absorption, up-conversion fluorescence, magnetic properties, cytotoxicity, and MRI were investigated in vivo and in vitro. The nanoparticle has an extremely strong optical fluorescence response and multiple excitation peaks in the visible light band under the 405 nm continuous-wave laser excitation. The nanoparticle was found to possess typical optical nonlinearity induced by two-photon absorption by ultrafast laser Z-scan technique. Two-photon excited fluorescence of visible red light at wavelengths of 615 nm and 701 nm, respectively, under excitation of the more biocompatible near-infrared (pulsed laser at 800 nm). In an in vitro MRI study, a T1 relaxation rate of 6.24 mM−1 s−1 was observed. MRI in vivo showed that the nanoparticles could significantly enhance the signal intensity in liver tissue. Conclusions: These results suggest that this sample has applied potential in visible light fluorescence imaging and MRI. [ABSTRACT FROM AUTHOR]

Toxic organic dyes released into aquatic sources as a result of industrial activities pose a significant threat to the environment. The removal of such dyes from water sources is a challenging task in the context of environmental emergencies. In this present effort, the strontium ferrite nanoparticles were synthesized by coprecipitation followed by a calcination method and is applied for photocatalytic degradation of such organic dyes. The ferrite nanoparticles were characterized by FTIR, XRD, VSM, SEM‐EDX, TEM, and HR‐TEM studies. In the existence of H2O2 under visible light, the catalyst performs efficient degradation of aniline blue (AB) and methyl violet (MV) dyes in a remarkably short interval of time. The superparamagnetic performance of the catalyst was confirmed by VSM, and thus it can be easily recovered from the degraded dye by applying an external magnet. The Fenton mechanism justifies the elevated rate of photo degradation, which generates hydroxyl and perhydroxyl radicals in the progress of the reaction. [ABSTRACT FROM AUTHOR]

This paper presents the methodology and computational results of simulated medical drug targeting (MDT) via induced magnetism intended for administering intravenous patient-specific doses of therapeutic agents in a Circle of Willis (CoW) model. The multi-physics computational model used in this work is from our previous works. The computational model is used to analyze pulsatile blood flow, particle motion, and particle capture efficiency in a magnetized region using the magnetic properties of magnetite (Fe3O4) and equations describing the magnetic forces acting on particles produced by an external cylindrical electromagnetic coil. A Eulerian–Lagrangian technique is implemented to resolve the hemodynamic flow and the motion of particles under the influence of a range of magnetic field strengths (Br = 2T, 4T, 6T, and 8T). Particle diameter sizes of 10 nm to 4 µm in diameter were assessed. Two dimensionless numbers are also investigated a priori in this study to characterize relative effects of Brownian motion (BM), magnetic force-induced particle motion, and convective blood flow on particle motion. Similar to our previous works, the computational simulations demonstrate that the greatest particle capture efficiency results for particle diameters within the micron range, specifically in regions where flow separation and vortices are at a minimum. Additionally, it was observed that the capture efficiency of particles decreases substantially with smaller particle diameters, especially in the superparamagnetic regime. The highest capture efficiency observed for superparamagnetic particles was 99% with an 8T magnetic field strength and 95% with a 2T magnetic field strength when analyzing 100 nm particles. For 10 nm particles and an 8T magnetic field strength, the particle capture efficiency was 48%, and for a 2T magnetic field strength the particle capture efficiency was 33%. Furthermore, it was found that larger magnetic field strengths, large particle diameter sizes (1 µm and above), and slower blood flow velocity increase the particle capture efficiency. The key finding in this work is that favorable capture efficiencies for superparamagnetic particles were observed in the CoW model for weak fields (Br < 4T) which demonstrates MDT as a possible viable treatment candidate for cardiovascular disease. [ABSTRACT FROM AUTHOR]

The TRAIL (TNF-related apoptosis-inducing ligand) apoptotic pathway is extensively exploited in the development of targeted antitumor therapy due to TRAIL specificity towards its cognate receptors, namely death receptors DR4 and DR5. Although therapies targeting the TRAIL pathway have encountered many obstacles in attempts at clinical implementation for cancer treatment, the unique features of the TRAIL signaling pathway continue to attract the attention of researchers. Special attention is paid to the design of novel nanoscaled delivery systems, primarily aimed at increasing the valency of the ligand for improved death receptor clustering that enhances apoptotic signaling. Optionally, complex nanoformulations can allow the encapsulation of several therapeutic molecules for a combined synergistic effect, for example, chemotherapeutic agents or photosensitizers. Scaffolds for the developed nanodelivery systems are fabricated by a wide range of conventional clinically approved materials and innovative ones, including metals, carbon, lipids, polymers, nanogels, protein nanocages, virus-based nanoparticles, dendrimers, DNA origami nanostructures, and their complex combinations. Most nanotherapeutics targeting the TRAIL pathway are aimed at tumor therapy and theranostics. However, given the wide spectrum of action of TRAIL due to its natural role in immune system homeostasis, other therapeutic areas are also involved, such as liver fibrosis, rheumatoid arthritis, Alzheimer's disease, and inflammatory diseases caused by bacterial infections. This review summarizes the recent innovative developments in the design of nanodelivery systems modified with TRAIL pathway-targeting ligands. [ABSTRACT FROM AUTHOR]

Micro and nano interdigitated electrode array (µ/n-IDEA) configurations are prominent working electrodes in the fabrication of electrochemical sensors/biosensors, as their design benefits sensor achievement. This paper reviews µ/n-IDEA as working electrodes in four-electrode electrochemical sensors in terms of two-dimensional (2D) planar IDEA and three-dimensional (3D) IDEA configurations using carbon or metal as the starting materials. In this regard, the enhancement of IDEAs-based biosensors focuses on controlling the width and gap measurements between the adjacent fingers and increases the IDEA's height. Several distinctive methods used to expand the surface area of 3D IDEAs, such as a unique 3D IDEA design, integration of mesh, microchannel, vertically aligned carbon nanotubes (VACNT), and nanoparticles, are demonstrated and discussed. More notably, the conventional four-electrode system, consisting of reference and counter electrodes will be compared to the highly novel two-electrode system that adopts IDEA's shape. Compared to the 2D planar IDEA, the expansion of the surface area in 3D IDEAs demonstrated significant changes in the performance of electrochemical sensors. Furthermore, the challenges faced by current IDEAs-based electrochemical biosensors and their potential solutions for future directions are presented herein. [ABSTRACT FROM AUTHOR]

Deterioration of soils over the years has led to a decline in crop yields and nutritional qualities, resulting from the oversupply of conventional fertilizers, which are unsustainable, costly and pose a threat to the environment. Nanoparticles are gaining a reputation in the field of agriculture for the remediation of soil degradation in a sustainable way. Recently, they have been recognized as potential fertilizers with properties that make them more absorbable and readily available for plant use than their bulk counterpart. However, there is less literature elaborating on the use of nanoparticles as agro-inputs for crop nutrition and protection. This review, therefore, provides insights into the application of nanoscaled nutrient elements such as silver, zinc, copper, iron, titanium, magnesium and calcium as fertilizers. In addition, the review explains the need for utilizing green synthesized nanomaterials as one of the ways to palliate the use of environmentally toxic chemicals in the cropping system and discusses the various benefits of nanoparticles, ranging from plant growth stimulation to defence against pathogens. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbon quantum dots are easily obtainable nanomaterials endowed with remarkable fluorescence properties for the detection of contaminations by heavy metals. In this report, we show that nanometric particles with high specificity for silver cations can be prepared by hydrothermal synthesis starting from citric and folic acid solutions. Solutions of these N-CQDs give a strong fluorescence emission in the violet region (385 nm) when excited at 330 nm, which can be quenched selectively by silver (I) cations at sub-nanomolar concentrations, while other cations do not give any effect. This remarkable feature was tentatively correlated with the stronger interactions between silver ion and small portions of the nanomaterial surface by comparing Ag+ and the isoelectronic Cd2+. [ABSTRACT FROM AUTHOR]

A novel endeavor based on the synthesis, characterization and study of a hybrid crystalline magnetic nanostructured material composed of bimetallic iron–rhodium nanoalloys, grown on nanodiamond nanotemplates, is reported in this study. The development of this hybrid magnetic nanomaterial is grounded in the combination of wet chemistry and thermal annealing under vacuum. In order to assess, evaluate and interpret the role and special properties of the nanodiamond supporting nanotemplates on the growth and properties of the bimetallic ferromagnetic Fe–Rh nanoparticles on their surfaces, unsupported free FeRh nanoparticles of the same nominal stoichiometry as for the hybrid sample were also synthesized. The characterization and study of the prepared samples with a range of specialized experimental techniques, including X-ray diffraction, transmission and scanning transmission electron microscopy with energy dispersive X-ray analysis, magnetization and magnetic susceptibility measurements and 57Fe Mössbauer spectroscopy, reveal that thermal annealing of the hybrid sample under specific conditions (vacuum, 700 °C, 30 min) leads to the formation of a rhodium-rich FeRh alloy nanostructured phase, with an average particle size of 4 nm and good dispersion on the surfaces of the nanodiamond nanotemplates and hard ferromagnetic characteristics at room temperature (coercivity of ~500 Oe). In contrast, thermal annealing of the unsupported free nanoparticle sample under the same conditions fails to deliver ferromagnetic characteristics to the FeRh nanostructured alloy phase, which shows only paramagnetic characteristics at room temperature and spin glass ordering at low temperatures. The ferromagnetic nanohybrids are proposed to be exploited in a variety of important technological applications, such as magnetic recording, magnetic resonance imaging contrast and magnetic hyperthermia agents. [ABSTRACT FROM AUTHOR]

The presence of nitrates in water in large amounts is one of the most dangerous health issues. The greatest risk posed by nitrates is hemoglobin oxidation, which results in Methemoglobin in the human body, resulting in Methemoglobinemia. There are many ways to eliminate nitrates from underground water. One of the most effective and selective methods is using zero-valent iron (ZVI) nanoparticles. ZVI nanoparticles can be easily synthesized by reducing ferric or ferrous ions using sodium borohydride. The prepared ZVI nanoparticles were examined by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), electron microscopy (TEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, and zeta potential. We aim to eliminate or reduce the nitrates in water to be at the acceptable range, according to the world health organization (WHO), of 10.0 mg/L. Nitrate concentration in water after and before treatment is measured using the UV scanning method at 220 nm wavelength for the synthetic contaminated water and electrochemical method for the naturally contaminated water. The conditions were optimized for obtaining an efficient removing process. The removal efficiency reaches about 91% at the optimized conditions. [ABSTRACT FROM AUTHOR]

The origin of fluorescence in carbon dots (C-dots) is still a puzzling phenomenon. The emission is, in most of the cases, due to molecular fluorophores formed in situ during the synthesis. The carbonization during C-dots processing does not allow, however, a fine control of the properties and makes finding the source of the fluorescence a challenging task. In this work, we present a strategy to embed a pre-formed fluorescent molecule, safranin O dye, into an amorphous carbonaceous dot obtained by citric acid carbonization. The dye is introduced in the melted solution of citric acid and after pyrolysis remains incorporated in a carbonaceous matrix to form red-emitting C-dots that are strongly resistant to photobleaching. Embedding dyes in amorphous C-dots represents an alternative method to optimize the emission in the whole visible spectrum. [ABSTRACT FROM AUTHOR]

The incorporation of ceramic nanoinclusions in carbon nanocomposites can induce additional functionality in the field of magnetic properties, piezoelectricity, etc. In this study, series of nanocomposites, consisting of different carbon nanoinclusions (carbon black, MWCNTs, graphene nanoplatelets, nanodiamonds) and magnetite nanoparticles incorporated into a commercially available epoxy resin were developed varying the filler type and concentration. Experimental data from the static tensile tests and dynamic mechanical analysis (DMA) demonstrated that the elastic tensile modulus and storage modulus of hybrid nanocomposites increase with an increase in filler content up to almost 100% due to the inherent filler properties and the strong interactions at the interface between the epoxy matrix and the nanoinclusions. Strong interactions are implied by the increasing values of the glass transition temperature recorded by differential scanning calorimetry (DSC). On the contrary, tensile strength and fracture strain of the nanocomposites were found to decrease with filler content. The results highlight the potentials and capabilities of developing hybrid multifunctional nanocomposites with enriched properties while holding their structural integrity. [ABSTRACT FROM AUTHOR]

Noble-metal nanoparticles (NMNPs), with their outstanding properties, have been arousing the interest of scientists for centuries. Although our knowledge of them is much more significant today, and we can obtain NMNPs in various sizes, shapes, and compositions, our interest in them has not waned. When talking about noble metals, gold, silver, and platinum come to mind first. Still, we cannot forget about elements belonging to the so-called platinum group, such as ruthenium, rhodium, palladium, osmium, and iridium, whose physical and chemical properties are very similar to those of platinum. It makes them highly demanded and widely used in various applications. This review presents current knowledge on the preparation of all noble metals in the form of nanoparticles and their assembling with carbon supports. We focused on the catalytic applications of these materials in the fuel-cell field. Furthermore, the influence of supporting materials on the electrocatalytic activity, stability, and selectivity of noble-metal-based catalysts is discussed. [ABSTRACT FROM AUTHOR]

Carbon-based nanoparticles create a huge group with substantial applications in the diagnosis and therapy of diseases. Herein, the mechanism of their outstanding properties was discussed to form a new insight for handling their issues and developing new applications in medical field. In addition, the strategies to remove the possible toxicity effects were gathered and a complete literature review about their production by economical methods was done. At the end of this article, the future applications of these nanoparticles and their new derivatives were noted. [ABSTRACT FROM AUTHOR]

In this study, we investigated electric explosion of iron wire in distilled water with different energy input adjusted by charging voltage. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS), showing the presence of iron and multiple iron-based compounds oxides with contents influenced by the experimental conditions. In particular, pure FeO(OH) nanoparticles were obtained using electric explosion of iron wire with energy input of 1125 J at charging voltage of 15 kV. Analysis of discharge current and resistive voltage data indicate that the high energy input induced by strong plasma discharge at high charging voltage is a key factor to form FeO(OH). This study presents a one-step method to synthesize FeO(OH) nanoparticles using electric explosion of iron wire. [ABSTRACT FROM AUTHOR]

Chemically pure (ligand-free) 5–70 nm iron nanoparticles were synthesized by electron-beam physical vapor deposition (EB-PVD) in a porous NaCl matrix. The influence of chemical composition, substrate temperature, and isothermal treatment on the dimensional, structural, and phase composition of nanoparticles in the Fe–O system was studied. For this purpose, independent molecular fluxes of Fe and NaCl were applied to a fixed substrate by electron-beam physical vapor deposition (EB-PVD) at substrate temperatures of 45–400°C to produce 3–30 wt.% Fe–NaCl condensates. With increasing iron content, substrate temperature, and heat treatment temperature, the average size of particles in the Fe–O system became greater. To study the oxidation kinetics of iron nanoparticles, the condensates produced at a substrate temperature of 45°C were isothermally treated in air at 200–650°C. The condensates were examined by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction, and aqueous solutions of the condensates by dynamic light scattering. Being of small size and thus having high adsorption capacity for air and moisture oxygen, iron exothermally oxidized in the condensate when the vacuum chamber was opened and the condensate was separated from the substrate. At different substrate temperatures and after heat treatment, the nanoparticles may contain pure iron and iron oxides Fe3O4 and Fe2O3. In the studied condensates, the α-Fe phase is present only when the iron content is more than 20 at.%. This is explained by the fact that not all nanoparticles (crystallites) have time to oxidize to the Fe3O4 phase with increase in their sizes. In addition, Fe3O4 nanoparticles additionally adsorb oxygen. The ratio between the atomic percentage of oxygen and iron depends on the amount of iron, decreases with increasing iron content of the condensate, and even exceeds the value for the stoichiometric composition of Fe2O3, being equal to 1.5. The study shows that the EB-PVD method is universal in the use of inorganic materials for the synthesis and retention of pure nanoparticles of metals and their oxides. [ABSTRACT FROM AUTHOR]

The drug loading efficiency of magnetite nanoparticles (MNPs) can be enhanced by coating with polyethylene glycol (PEG) which is a biocompatible polymer. The PEG-coated MNPs could be the potential candidates for carrying the drug molecules to the targeted sites. In this study, size-controlled MNPs were synthesized and functionalized with PEG of molecular weights 700, 2000 and 5000. The MNPs and PEGylated MNPs (PMNPs) samples were characterized through X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and surface area and pore size measurements by Brunauer, Emmett and Teller (BET) and Barrett–Joyner–Halenda (BJH) methods. The diffraction data showed that MNPs are purely crystalline with face cubic crystal structure, whereas the spherical shape of the particles was confirmed by TEM. The TGA supports thermal stability of nanoparticles which was markedly enhanced by coating with PEG. The BJH data (hysteresis loops) showed that MNPs were mesoporous in nature. After characterization, the PEGylated MNPs were loaded with gallic acid (GA). The spectroscopic evidences regarding the successful PEGylation and loading of GA onto PMNPswere acquired from FTIR spectroscopy. The in vitro sustained drug release efficacy of PMNPs was evaluated via UV–visible spectroscopy. Among all the synthesized samples, P750MNPs-10 showed the highest % drug release i.e., 98% into phosphate buffer saline (PBS) solution of pH 4.4 and 90% in PBS of pH 7.4. The highest % drug release at pH 10 may be attributed to smaller particle size with high surface area. The highest % drug release can also be associated with the weak interactions between P750MNPs-10 and GA through hydrogen bonding. [ABSTRACT FROM AUTHOR]

Nanocarriers-based immobilization strategies are a novel concept in the enhancement of enzyme stability, shelf life and efficiency. A wide range of natural and artificial supports have been assessed for their efficacy in enzyme immobilization. Nanomaterials epitomize unique and fascinating matrices for enzyme immobilization. These structures include carbon nanotubes, superparamagnetic nanoparticles and nanofibers. These nano-based supports offer stable attachment of enzymes, thus ensuring their reusability in diverse industrial applications. This review attempts to encompass recent developments in the critical role played by nanotechnology towards the improvement of the practical applicability of microbial enzymes. Nanoparticles are increasingly being used in combination with various polymers to facilitate enzyme immobilization. These endeavors are proving to be conducive for enzyme-catalyzed industrial operations. In recent years the diversity of nanomaterials has grown tremendously, thus offering endless opportunities in the form of novel combinations for various biotransformation experimentations. These nanocarriers are advantageous for both free enzymes and whole-cell immobilization, thus demonstrating to be relatively effective in several fermentation procedures. [ABSTRACT FROM AUTHOR]

The search for new nanomaterials has brought to the multifactorial industry several opportunities for use and applications for existing materials. Carbon nanotubes (CNT), for example, present excellent properties which allow us to assume a series of applications, however there is concern in the industrial scope about possible adverse health effects related to constant exposure for inhalation or direct skin contact. Thus, using cell models is the fastest and safest way to assess the effects of a new material. The aim of this study was to investigate the cytotoxic profile in LA9 murine fibroblast lineage, of a new multi-walled carbon nanotube (MWCNT) that was functionalized with tetraethylenepentamine (TEPA) to obtain better physical-chemical characteristics for industrial use. The modifications presented in the CNT cause concern, as they can change its initial characteristics, making this nanomaterial harmful. HR-TEM, FE-SEM and zeta potential were used for the characterization. Cytotoxicity and cell proliferation tests, oxidative and nitrosative stress analyzes and inflammatory cytokine assay (TNF-α) were performed. The main findings demonstrated a reduction in cell viability, increased release of intracellular ROS, accompanied by an increase in TNF-α, indicating an important inflammatory profile. Confirmation of the data was performed by flow cytometry and ImageXpress with apoptosis/necrosis markers. These data provide initial evidence that OCNT-TEPA has a cytotoxic profile dependent on the concentration of LA9 fibroblasts, since there was an increase in free radicals, inflammation induction and cell death, suggesting that continuous exposure to this nanoparticle can cause damage to different tissues in the organism. [ABSTRACT FROM AUTHOR]

Nanostructured titania (TiO2) is the most widely applied semiconducting oxide for a variety of purposes, and it is found in many commercial products. The vast majority of uses rely on its photo-activity, which, upon light irradiation, results in excited states that can be used for diverse applications. These range from catalysis, especially for energy or environmental remediation, to medicine—in particular, to attain antimicrobial surfaces and coatings for titanium implants. Clearly, the properties of titania are enhanced when working at the nanoscale, thanks to the increasingly active surface area. Nanomorphology plays a key role in the determination of the materials' final properties. In particular, the nucleation and growth of nanosized titania onto carbon nanostructures as a support is a hot topic of investigation, as the nanocarbons not only provide structural stability but also display the ability of electronic communication with the titania, leading to enhanced photoelectronic properties of the final materials. In this concise review, we present the latest progress pertinent to the use of nanocarbons as templates to tailor nanostructured titania, and we briefly review the most promising applications and future trends of this field. [ABSTRACT FROM AUTHOR]

Owing to their inherent features like smaller size and higher surface area exposed to reactants, iron oxide nanoparticles have gained enormous interest and are extensively used as magnetically recyclable catalysts for various organic reactions. Herein, we report highly hydrophilic, non-aggregated, and strongly positively charged (ζ potential: + 45.7 mV) ultra-small cerium cations/complexes- stabilized maghemite nanoparticles in water as an efficient and reusable nanoscaled catalyst for the nucleophilic addition reaction of various amines with α,β-unsaturated carbonyl compounds to give corresponding β-amino derivatives under ultrasonic irradiation. The developed protocol provides several merits such as high product yields, mild reaction conditions, reusable catalyst and easy workup. [ABSTRACT FROM AUTHOR]

Preventing water pollution and conserving water are major issues in the context of population growth and worldwide pollution, calling for advanced remediation techniques. Classical remediation techniques of water cleaning such as membrane adsorption are able to separate pollutants from water, yet the separated pollutants require additional treatment or disposal. Therefore, techniques that degrade the pollutant appear promising, provided that pollutants are organic and degradable. Here, we review the enzymatic degradation of organic pollutants with focus on methods to immobilize enzymes and nanoparticles as support materials. We discuss the degradation of pesticides, dyes, phenolic compounds and antibiotics. [ABSTRACT FROM AUTHOR]

The study on the health effects of combined exposure to various contaminants has been recommended by many authors. The objective of the present study was to examine the effects of the co-exposure to hematite and amorphous silicon dioxide (A-SiO2) nanoparticles on the human lung A549 cell line. The A549 cell line was exposed to 10, 50, 100, and 250 µg/ml concentrations of hematite and A-SiO2 nanoparticles both independently and in combination. Their toxicity in both circumstances was investigated by MTT, intracellular reactive oxygen species, cell glutathione content, and mitochondrial membrane potential tests, and the type of interaction was investigated by statistical analysis using Statistical Package for Social Sciences (SPSS, v. 21). Results showed that the independent exposure to either hematite or A-SiO2 compared with the control group produced more toxic effects on the A549 cell line. The toxicity of combined exposure of the nanoparticles was lower compared with independent exposure, and antagonistic interactive effects were detected. The findings of this study could be useful in clarifying the present debate on the health effects of combined exposure of hematite and A-SiO2 nanoparticles. Because of the complexities of combined exposures, further studies of this kind are recommended. [ABSTRACT FROM AUTHOR]

Magnetic drug carriers are aimed at transporting the loaded drugs to the target site with the application of an external field. To realize this, a clever design of magnetic nanoparticles and their surface modification have to be achieved. Herein, we report the synthesis of ErFeO3 nanoparticles and their magnetic characteristics. In addition, we report a β-cyclodextrin-polyethylene glycol-folate conjugate and utilize it for coating the magnetic nanoparticles. The crystallinity and grain size of the nanoparticles are characterized using X-ray diffraction. The elemental composition of the nanoparticles and their orbital states are determined using XPS spectroscopy. The polymer-coated nanoparticles are soft ferromagnetic. The anticancer drug, camptothecin, is loaded on the polymer-coated nanoparticles with a loading percentage of about 88%. The efficacy of camptothecin gets enhanced when loaded on the magnetic nanocarrier and released in a sustained manner. Compared to the free form, the drug loaded on the nanocarrier shows an enhanced anticancer activity. [ABSTRACT FROM AUTHOR]

Copper oxide nanoparticles (CuO NPs) have anticancer and antimicrobial activities. Moreover, they have a contrast enhancing effect in both MRI and ultrasound. Nonetheless, encapsulation is needed to control their toxic side effects and a mechanism for release on demand is required. A methodology is introduced herein for encapsulating and releasing CuO NPs from micelles by ultrasound induced hyperthermia and monitoring the process by MRI. For this aim, CuO NPs loaded poly(ethylene glycol)-block-poly(D,L-lactic acid) (PEG-b-PLA) micelles were prepared. Then, the profile of copper release with application of ultrasound was examined as a function of time and temperature using a colorimetric method. Finally, T1 weighted MRI images of suspensions and ex vivo poultry liver samples containing the CuO NPs loaded micelles were acquired before and after ultrasound application. The results confirmed that: (i) encapsulated NPs are detectible by MRI T1 mapping, depicting substantial T1 shortening from 1872 ± 62 ms to 683 ± 20 ms. (ii) Ultrasonic hyperthermia stimulated the NPs release with an about threefold increase compared to non-treated samples. (iii) Releasing effect was clearly visible by T1-weighted imaging (mean signal increase ratio of 2.29). These findings can potentially lead to the development of a new noninvasive methodology for CuO NPs based theranostic process. [ABSTRACT FROM AUTHOR]

The green synthesis of nanoparticles (NPs) using living cells is a promising and novelty tool in bionanotechnology. Chemical and physical methods are used to synthesize NPs; however, biological methods are preferred due to its eco-friendly, clean, safe, cost-effective, easy, and effective sources for high productivity and purity. High pressure or temperature is not required for the green synthesis of NPs, and the use of toxic and hazardous substances and the addition of external reducing, stabilizing, or capping agents are avoided. Intra- or extracellular biosynthesis of NPs can be achieved by numerous biological entities including bacteria, fungi, yeast, algae, actinomycetes, and plant extracts. Recently, numerous methods are used to increase the productivity of nanoparticles with variable size, shape, and stability. The different mechanical, optical, magnetic, and chemical properties of NPs have been related to their shape, size, surface charge, and surface area. Detection and characterization of biosynthesized NPs are conducted using different techniques such as UV–vis spectroscopy, FT-IR, TEM, SEM, AFM, DLS, XRD, zeta potential analyses, etc. NPs synthesized by the green approach can be incorporated into different biotechnological fields as antimicrobial, antitumor, and antioxidant agents; as a control for phytopathogens; and as bioremediative factors, and they are also used in the food and textile industries, in smart agriculture, and in wastewater treatment. This review will address biological entities that can be used for the green synthesis of NPs and their prospects for biotechnological applications. [ABSTRACT FROM AUTHOR]

Magnetic ferrite materials have been extensively studied for a range of technological applications, such as magnetic motors, recording media, and millimetre-wave devices. In this context, the nanosized epsilon phase of Fe2O3 (ϵ-Fe2O3) attracts significant attention due to its high coercive field at room temperature. Here, we report the in-situ aerogel nanoreactor growth of magnetic ϵ-Fe2O3 nanoparticles, exhibiting a coercive field (Hc) of 4000 Oe. We show that the control of nanoreactor plays an important role in the growth of ϵ-Fe2O3 nanoparticles. The findings provide a versatile reaction pathway for the growth of magnetically hard ferrite nanoparticles. [ABSTRACT FROM AUTHOR]

Shape-controlled metal nanomaterials are considered as a unique class of catalysts because of their synergistic size- and shape-dependent catalytic properties. This work reports the synthesis of a novel size- and shape-controlled catalyst, consisting of highly dispersed MnOx nanoparticles (average particle size of 4.5 nm) on shape-controlled SiO2 nanospheres (250–300 nm) for selective cyclohexene oxidation using air as the oxidant under solvent- and base-free conditions. The MnOx/SiO2 catalyst exhibited an excellent cyclohexene conversion (~ 92%) with a high selectivity (~ 96%) to the allylic products (2-cyclohexene-ol and 2-cyclohexene-one) under mild conditions, outperforming various SiO2 supported CoOx, FeOx, and CuOx catalysts. The better performance of shape-controlled MnOx/SiO2 nanocatalyst is due to high redox nature of Mn, uniform dispersion of smaller sized MnOx nanoparticles, and synergetic interaction between MnOx and SiO2 spheres, as evidenced by XPS and TEM studies. Further, the MnOx/SiO2 catalyst could be reused at least 5 times for selective cyclohexene oxidation with a negligible loss in its catalytic performance, indicating the excellent stability of shape-controlled metal nanocatalysts in organic synthesis under economically viable and mild conditions. Shape-controlled MnOx/SiO2 nanocatalyst shows an excellent catalytic activity and a high selectivity to allylic products in the oxidation of cyclohexene under mild conditions [ABSTRACT FROM AUTHOR]

Superparamagnetic iron oxide nanoparticles (SPIONs) and core-shell type nanoparticles, consisting of SPIONs coated with mesoporous silica and/or lipid, were synthesised and tested for their potential theranostic applications in drug delivery, magnetic hyperthermia and as a contrast agent. Transmission Electron Microscopy (TEM) confirmed the size of bare and coated SPIONs was in the range of 5–20 nm and 100–200 nm respectively. The superparamagnetic nature of all the prepared nanomaterials as indicated by Vibrating Sample Magnetometry (VSM) and their heating properties under an AC field confirm their potential for hyperthermia applications. Scanning Column Magnetometry (SCM) data showed that extrusion of bare-SPION (b-SPION) dispersions through a 100 nm polycarbonate membrane significantly improved the dispersion stability of the sample. No sedimentation was apparent after 18 h compared to a pre-extrusion estimate of 43% settled at the bottom of the tube over the same time. Lipid coating also enhanced dispersion stability. Transversal relaxation time (T2) measurements for the nanoparticles, using a bench-top relaxometer, displayed a significantly lower value of 46 ms, with a narrow relaxation time distribution, for lipid silica coated SPIONs (Lip-SiSPIONs) as compared to that of 1316 ms for the b-SPIONs. Entrapment efficiency of the anticancer drug, Doxorubicin (DOX) for Lip-SPIONs was observed to be 35% which increased to 58% for Lip-SiSPIONs. Moreover, initial in-vitro cytotoxicity studies against human breast adenocarcinoma, MCF-7 cells showed that % cell viability increased from 57% for bSPIONs to 82% for Lip-SPIONs and to 87% for Lip-SiSPIONs. This suggests that silica and lipid coatings improve the biocompatibility of bSPIONs significantly and enhance the suitability of these particles as drug carriers. Hence, the magnetic nanomaterials prepared in this work have potential theranostic properties as a drug carrier for hyperthermia cancer therapy and also offer enhancement of contrast agent efficacy and a route to a significant increase in dispersion stability. [ABSTRACT FROM AUTHOR]

Novel Palladium nanoparticles supported nano Magnesium ferrite catalyst (Pd/MgFe2O4) was synthesized by one-step ultrasound assisted coprecipitation. In-situ formed by-products assisted salt cage calcination approach was employed to control the particle size by minimizing the risk of nanoparticle aggregation during calcination. Palladium nanoparticles were grafted on the surface of nanocrystalline MgFe2O4 without using any reducing agents, capping agents and surface modifiers. The catalyst preparation method was having minimum process operations and can be used for synthesis of various potential nanocatalytic systems. The catalyst was extensively characterized by using various techniques SEM-EDS, TEM, FT-IR, XPS, XRD, VSM, BET, and ICP-AES. Pd/MgFe2O4 was magnetically separable and shown its potential utility for ligand less Suzuki-Miyaura coupling reaction using green solvent system Water and Ethanol. The nanocatalyst shows consistent activity and excellent reusability in the synthesis of Biaryls with excellent yields. In addition, the prepared catalytic nanoparticles were successfully applied in the synthesis of 5-(4-phenoxyphenyl)-7H-pyrrolo[2,3-d]pyrimidin-4-ylamine an intermediate for preparing the marketed anticancer drug PCI-32765 under the name IMBRUVICA® (Ibrutinib-BTK inhibitor). [ABSTRACT FROM AUTHOR]

In this research, Fe3O4/SiO2/TiO2-Ag (FST-Ag) nanoparticles were provided with chemical techniques (sol–gel) during successive steps. At first, Fe3O4 nanoparticles were synthesized via co-precipitation method. Then, Fe3O4/SiO2 (FS) core/shell particles were prepared in presence of different amounts of TEOS precursor. Next, deposition of TiO2 shells was obtained using hydroxypropyl cellulose (HPC) polymer (as a surfactant) to prevent the agglomeration. Finally, Ag nanoparticles deposited on Fe3O4/SiO2/TiO2 (FST) core/shell/shell structure using polyvinyl pyrrolidone (PVP) polymer. The prepared nanoparticles were characterized by XRD, FESEM (with EDX), and TEM techniques. Magnetic properties of the prepared composites were studied by VSM. The result revealed Fe3O4/SiO2/TiO2-Ag nanoparticle photo-catalyst with core/shell magnetic structure were synthesized successfully at each step in presences of suitable additives. Photocatalytic performance of the nanoparticles indicated that Ag nanoparticles increased the removal of methylene blue up to 83% after 3 h. The magnetic properties of these particles also showed that after deposition of layers, nanoparticles have a good ability for the recovery and separation from the solution. [ABSTRACT FROM AUTHOR]