Ultrasound assisted phytosynthesis of iron oxide nanoparticle

Short-term airborne ultrasound induced cell death in tobacco cells and changed their wall components

The effects of low-intensity ultrasound on plants such as piezoelectric and ultrasonic water baths, on plants have been extensively studied. However, the specific effect of airborne ultrasound on plant cells has yet to be reported. The present study was conducted to elucidate the physiological responses of plant cells to airborne US. Homogeneous suspension-cultured tobacco cells (Nicotiana tabacum L. cv Burley 21) were subjected to airborne US at 24 kHz in two pulsatile and continuous modes for 10 and 20 s. The study's outcome revealed that airborne US triggered the production of H2O2, elevated internal calcium concentration, and reduced antioxidant capacity upon cavitation. Alteration of covalently bound peroxidase and other wall-modifying enzyme activities was accompanied by reduced cellulose, pectin, and hemicellulose B but increased lignin and hemicellulose A. The biomass and viability of tobacco cells were also significantly decreased by airborne US, which ultimately resulting in PCD and secondary necrosis. The results highlight the potential risks of even short-time exposure to the airborne US on plant physiology and cell wall chemical composition raising significant concerns about its implications.

Iron oxide nanoparticles derived from Polyalthia korintii (Dunal) Benth. & Hook. F leaves extract exhibits biological and dye degradation potentials

Green synthesis of iron oxide nanoparticles using plant extracts is of tremendous interest owing to its cost effectiveness, ecofriendly and high efficiency compared to physical and chemical approaches. In the current study, we describe a green approach for producing iron oxide nanoparticles utilizing Polyalthia korintii aqueous leaf extract (PINPs). The prepared PINPs were assessed of their biological and dye degradation potentials. The physico-chemical characterization of PINPs using UV-Visible spectrophotometer, Fourier Transform Infrared Spectroscopy, X-Ray Diffraction studies, Field emission Scanning Electron Microscopy and Energy Dispersive X-ray spectroscopy analysis confirmed the synthesized sample comprised of iron oxide entity, predominantly spherical with the size range of 40-60 nm. Total Phenolic Content of PINPs is 59.36 ± 1.64 µg GAE/mg. The PINPs exhibited 89.78 ± 0.07% DPPH free radical scavenging and 28.7 ± 0.21% ABTS cation scavenging activities. The antibacterial activities were tested against different gram-positive and gram-negative bacteria and PINPs were more effective against Enterococcus faecalis and Klebsiella pneumoniae. Cytotoxicity of PINPs against K562 and HCT116 were measured and IC50 values were found to be 84.99 ± 4.3 µg/ml and 79.70 ± 6.2 µg/ml for 48 h respectively. The selective toxicity of PINPs was demonstrated by their lowest activity on lymphocytes, HEK293 cells, and erythrocytes. The toxicity (LC 50 values) against first, second, third and fourth instar larvae of Culex quinquefasciatus was 40 ± 1.5 mg/mL, 45 ± 0.8 mg/mL, 99 ± 2.1 mg/mL and 120 ± 3.5 mg/mL respectively. Finally, PINPs were utilized to as a catalyst for removal of textile dyes like Methylene blue and methyl orange in a fenton-like reaction. The results showed 100% dye degradation efficiency in a fenton like reaction within 35 min. Thus, the green synthesized PINPs exhibit antioxidant, antibacterial, antiproliferative, larvicidal and dye degradation potentials, indicating their suitability for biological and environmental applications.

Magnetic iron oxides nanocomposites: synthetic techniques and environmental applications for wastewater treatment

Nanomaterials are an emerging class of compounds with potential to advance technology for wastewater treatment. There are many toxic substances in industrial wastewater that are dangerous to the aquatic ecosystem and public health. These pollutants require the development of novel techniques to remove them from the environment. Iron oxide nanoparticles are being studied and develop as new technology to address the problem of environmental pollution due to their unique properties and effectiveness against different kind of pollutants. A variety of modified iron oxide nanoparticles have been developed through extensive research that mitigates the shortcomings of aggregation or oxidation and enhances their efficiency as novel remediator against environmental pollutants. In this review, we present synthetic approaches used for the preparation of iron oxide nanoparticles and their corresponding nanocomposites, along with the processes in which the materials are used as adsorbent/photocatalysts for environmental remediation. Applications explored includes adsorption of dyes, photocatalytic degradation of dyes, and adsorption of heavy metal ions. The use of iron oxides nanocomposite in real wastewater samples and recyclability of adsorbents and photocatalysts were also explored.

A sustainable green-approach for biofabrication of chitosan nanoparticles, optimization, characterization, its antifungal activity against phytopathogenic Fusarium culmorum and antitumor activity

Chitosan is a natural non-toxic, biocompatible, biodegradable, and mucoadhesive polymer. It also has a broad spectrum of applications such as agriculture, medical fields, cosmetics and food industries. In this investigation, chitosan nanoparticles were produced by an aqueous extract of Cympopogon citratus leaves as a reducing agent. According to the SEM and TEM micrographs, CNPs had a spherical shape, and size ranging from 8.08 to 12.01 nm. CNPs have a positively charged surface with a Zeta potential of + 26 mV. The crystalline feature of CNPs is determined by X-ray diffraction. There are many functional groups, including C꞊C, CH2-OH, C-O, C-S, N-H, CN, CH and OH were detected by FTIR analysis. As shown by the thermogravimetric study, CNPs have a high thermal stability. For the optimization of the green synthesis of CNPs, a Face centered central composite design (FCCCD) with 30 trials was used. The maximum yield of CNPs (13.99 mg CNPs/mL) was produced with chitosan concentration 1.5%, pH 4.5 at 40 °C, and incubation period of 30 min. The antifungal activity of CNPs was evaluated against phytopathogenic fungus; Fusarium culmorum. A 100% rate of mycelial growth inhibition was gained by the application of 20 mg CNPs/mL. The antitumor activity of the green synthesized CNPs was examined using 6 different cell lines, the viability of the cells reduced when the concentration of green synthesized CNPs increased, the IC50 dose of the green synthesized CNPs on the examined cell lines HePG-2, MCF-7, HCT-116, PC-3, Hela and WI-38 was 36.25 ± 2.3, 31.21 ± 2.2, 67.45 ± 3.5, 56.30 ± 3.3, 44.62 ± 2.6 and 74.90 ± 3.8; respectively.

Biogenic synthesis of iron oxide nanoparticles using leaf extract of Spilanthes acmella: antioxidation potential and adsorptive removal of heavy metal ions

The sequestration of contaminants from wastewater, such as heavy metals, has become a major global issue. Multiple technologies have been developed to address this issue. Nanotechnology is attracting significant interest as a new technology, and numerous nanomaterials have been produced for sequestrating heavy metals from polluted water due to their superior properties arising from the nanoscale effect. This study reports biosynthesis of iron oxide nanoparticles (IO-NPs) and their applications for adsorptive sequestration of various metal ions from aqueous solutions. Biosynthesis of IO-NPs has been carried out by using leaf extract of Spilanthes acmella, a medicinal plant. FTIR analysis of the leaf extract and biosynthesized IO-NPs marked the role of various functional groups in biosynthesis of IO-NPs. FESEM analysis revealed the average size range of IO-NPs as 50 to 80 nm, while polydisperse nature was confirmed by DLS analysis. EDX analysis revealed the presence of Fe, O, and C atoms in the elemental composition of the NPs. The antioxidant potential of the biosynthesized IO-NPs (IC50 = 136.84 µg/mL) was confirmed by DPPH assay. IO-NPs were also used for the adsorptive removal of As3+, Co2+, Cd2+, and Cu2+ ions from aqueous solutions with process optimization at an optimized pH (7.0) using dosage of IO-NPs as 0.6 g/L (As3+ and Co2+) and 0.8 g/L (Cd2+ and Cu2+). Adsorption isotherm analysis revealed the maximum adsorption efficiency for As3+ (21.83 mg/g) followed by Co2+ (20.43 mg/g), Cu2+ (15.29 mg/g), and Cd2+ (13.54 mg/g) using Langmuir isotherm model. The biosynthesized IO-NPs were equally efficient in the simultaneous sequestration of these heavy metal ions signifying their potential as effective nanoadsorbents.

Application of Iron Nanoparticle-Based Materials in the Food Industry

Due to their different properties compared to other materials, nanoparticles of iron and iron oxides are increasingly used in the food industry. Food technologists have especially paid attention to their ease of separation by magnetic fields and biocompatibility. Unfortunately, the consumption of increasing amounts of nanoparticles has raised concerns about their biotoxicity. Hence, knowledge about the applicability of iron nanoparticle-based materials in the food industry is needed not only among scientists, but also among all individuals who are involved in food production. The first part of this article describes typical methods of obtaining iron nanoparticles using chemical synthesis and so-called green chemistry. The second part of this article describes the use of iron nanoparticles and iron nanoparticle-based materials for active packaging, including the ability to eliminate oxygen and antimicrobial activity. Then, the possibilities of using the magnetic properties of iron nano-oxides for enzyme immobilization, food analysis, protein purification and mycotoxin and histamine removal from food are described. Other described applications of materials based on iron nanoparticles are the production of artificial enzymes, process control, food fortification and preserving food in a supercooled state. The third part of the article analyzes the biocompatibility of iron nanoparticles, their impact on the human body and the safety of their use.

A recent update on green synthesized iron and iron oxide nanoparticles for environmental applications

Nanotechnology is considered the budding discipline in various fields of science and technology. In this review, the various synthesis methods of iron and iron oxide nanoparticles were summarised with more emphasis on green synthesis - a sustainable and eco-friendly method. The mechanism of green synthesis of these nanomaterials was reviewed in recent literature. The magnetic properties of these nanomaterials were briefed which makes them unique in the family of nanomaterials. An overview of various removal methods for the pollutants such as dye, heavy metals, and emerging contaminants using green synthesized iron and iron oxide nanoparticles is discussed. The mechanism of pollutant removal methods like Fenton-like degradation, photocatalytic degradation, and adsorption techniques was also detailed. The review is concluded with the challenges and possible future aspects of these nanomaterials for various environmental applications.

Disrupting biofilm and eradicating bacteria by Ag-Fe3O4@MoS2 MNPs nanocomposite carrying enzyme and antibiotics

In this study, novel multilayered magnetic nanoparticles (ML-MNPs) loaded with DNase and/or vancomycin (Vanc) were fabricated for eliminating multispecies biofilms. Iron-oxide MNPs (IO-core) (500-800 nm) were synthesized via co-precipitation; further, the IO-core was coated with heavy-metal-based layers (Ag and MoS₂ NPs) using solvent evaporation. DNase and Vanc were loaded onto the outermost layer of the ML-MNP formed by nanoporous MoS₂ NPs through physical deposition and adsorption. The biofilms of S. mutans or E. faecalis (or both) were formed in a brain-heart-infusion broth (BHI) for 3 days, followed by treatment with ML-MNPs for 24 h. The results revealed that coatings of Ag (200 nm) and ultrasmall MoS₂ (20 nm) were assembled as outer layers of ML-MNPs successfully, and they formed Ag-Fe₃O₄@MoS₂ MNPs (3-5 μm). The DNase-Vanc-loaded MNPs caused nanochannels digging and resulted in the enhanced penetration of MNPs towards the bottom layers of biofilm, which resulted in a decrease in the thickness of the 72-h biofilm from 48 to 58 μm to 0-4 μm. The sustained release of Vanc caused a synergistic bacterial killing up to 96%-100%. The heavy-metal-based layers of MNPs act as nanozymes to interfere with bacterial metabolism and proliferation, which adversely affects biofilm integrity. Further, loading DNase/Vanc onto the nanoporous-MoS₂-layer of ML-MNPs promoted nanochannel creation through the biofilm. Therefore, DNase-and Vanc-loaded ML-MNPs exhibited potent effects on biofilm disruption and bacterial killing.

Smart and Multi-Functional Magnetic Nanoparticles for Cancer Treatment Applications: Clinical Challenges and Future Prospects

Iron oxide nanoparticle (IONPs) have become a subject of interest in various biomedical fields due to their magnetism and biocompatibility. They can be utilized as heat mediators in magnetic hyperthermia (MHT) or as contrast media in magnetic resonance imaging (MRI), and ultrasound (US). In addition, their high drug-loading capacity enabled them to be therapeutic agent transporters for malignancy treatment. Hence, smartening them allows for an intelligent controlled drug release (CDR) and targeted drug delivery (TDD). Smart magnetic nanoparticles (SMNPs) can overcome the impediments faced by classical chemo-treatment strategies, since they can be navigated and release drug via external or internal stimuli. Recently, they have been synchronized with other modalities, e.g., MRI, MHT, US, and for dual/multimodal theranostic applications in a single platform. Herein, we provide an overview of the attributes of MNPs for cancer theranostic application, fabrication procedures, surface coatings, targeting approaches, and recent advancement of SMNPs. Even though MNPs feature numerous privileges over chemotherapy agents, obstacles remain in clinical usage. This review in particular covers the clinical predicaments faced by SMNPs and future research scopes in the field of SMNPs for cancer theranostics.

Iron Oxide Nanoparticles-Plant Insignia Synthesis with Favorable Biomedical Activities and Less Toxicity, in the “Era of the-Green”: A Systematic Review

In the era of favoring environment-friendly approaches for pharmaceutical synthesis, “green synthesis” is expanding. Green-based nanomedicine (NM), being less toxic and if having biomedical acceptable activities, thence, the chemical methods of synthesis are to be replaced by plants for reductive synthesis. Iron oxide nanoparticles (IONPs) exhibited remarkable anti-microbial and anti-cancer properties, besides being a drug delivery tool. However, owing to limitations related to the chemical synthetic method, plant-mediated green synthesis has been recognized as a promising alternative synthetic method. This systematic review (SR) is addressing plant-based IONPs green synthesis, characteristics, and toxicity studies as well as their potential biomedical applications. Furthermore, the plant-based green-synthesized IONPs in comparison to nanoparticles (NPs) synthesized via other conventional methods, characteristics, and efficacy or toxicity profiles would be mentioned (if available). Search strategy design utilized electronic databases including Science Direct, PubMed, and Google Scholar search. Selection criteria included recent clinical studies, available in the English language, published till PROSPERO registration. After screening articles obtained by first electronic database search, by title, abstract and applying the PICO criteria, the search results yielded a total of 453 articles. After further full text filtrations only 48 articles were included. In conclusion, the current SR emphasizes the perspective of the IONPs plant-mediated green synthesis advantage(s) when utilized in the biomedical pharmaceutical field, with less toxicity.

TiO2-Modified Magnetic Nanoparticles (Fe3O4) with Antibacterial Properties

This paper presents the synthesis and characteristics of Fe₃O₄/C/TiO₂ hybrid magnetic nanomaterials with antibacterial properties. The materials used were obtained using a microwave-assisted two-stage precipitation method. In the first stage, magnetite nanoparticles (Fe₃O₄) were prepared with the precipitation method, during which an additional glucose layer was placed on them. Next, the surface of Fe₃O₄ nanoparticles was covered by TiO₂. It was observed that the addition of carbon and titanium dioxide caused a decrease in the average size of magnetite crystallites from 15.6 to 9.2 nm. Materials with varying contents of anatase phase were obtained. They were characterized in terms of phase composition, crystallite size, specific surface area, surface charge and the kinds of function groups on the surface. The results show a successful method of synthesizing hybrid magnetic nanoparticles, stable in a solution, with antibacterial properties under direct solar light irradiation. Compared to classical materials based on TiO₂ and used for water disinfection, the obtained photocatalytic nanomaterials have magnetic properties. Owing to this fact, they can be easily removed from water once their activity under direct irradiance in a given process has completed.

Influence of bionanoparticles to treat a slaughterhouse wastewater

Treatment of effluents from animal slaughterhouse industries is indispensable, standing out coagulation/flocculation/sedimentation processes. Bionanoparticles (BioNPs) (nanoparticles (NPs) functionalized with Moringa extracts (MO)) were studied as an alternative natural coagulant that would contribute to the microbial load reduction, without increasing the treated effluent toxicity. MO extracts were prepared with different salts, and then, in a kinetics study, different NPs mass and coagulant dosages were evaluated. In the best-defined conditions, microbial load, toxicity tests for the bioindicator Lactuca sativa, and NPs reuse evaluation were performed. Removals of 96.14% turbidity and 43.63% UV254nm were achieved when using 500 mg L-1 of BioNPs containing 60 mg of NPs for every 20 mL of MO extract prepared with 0.1 M CaCl2. The BioNPs with an external magnetic field also decreased the sedimentation time from 140 to 10 min compared to MO, and the process efficiency did not expressively decrease after reusing the recovered NPs. Through toxicity tests, BioNPs were not considered to leave residuals toxic to the Lactuca sativa in the treated effluent. Besides, the microbial load reduction was 97.33% for heterotrophic microorganisms and total mesophiles and 99.25% for moulds/yeasts. Therefore, a satisfactory primary treatment was achieved, contributing to the sustainability of industries.

A strategy to enhance the photocatalytic efficiency of α-Fe2O3

The photocatalytic dye degradation of pure α-Fe₂O₃ and different concentration of Co doped α-Fe₂O₃ is explored. Facile hydrothermal method were employed to prepare pristine, 2% and 4% Co-Fe₂O₃ nanoparticles. Further, synthesized product confirmation studies were employed from X-ray diffraction, UV-vis spectrometry, Fourier-transform infrared, Raman, scanning electron microscope and transmission electron microscope studies. The rhombohedral nanoparticles developed were enhanced photocatalytic action. Photocatalytic dye degradation studies were analyzed for prepared three samples and the photocatalytic efficacy of the obtained photocatalysts was compared experimentally. Methylene blue dye was degraded under UV-light irradiation with 364 nm. The results showed that 4% Co doped α-Fe₂O₃ sample exhibited better dye degradation with 92% efficiency. The 4% doping of cobalt ions enhanced the photocatalytic property of Fe₂O₃ and is a good candidate for methylene blue dye degradation above 90%. In addition, strategy for photocatalytic efficiency enhancement was proposed.

Recent innovations of ultrasound green technology in herbal phytochemistry: A review

Ultrasound (US) has become one of the most important techniques in green chemistry and emerging technologies. Many research investigations documented the usefulness of US in a wide range of applications in food science, nanotechnology, and complementary medicine, where effective extraction of natural products is important. However, as with all novel technologies, US has advantages and limitations that require clarification for full adaptation at an industrial scale. The present review discusses recent applications of US in herbal phytochemistry with the emphasis on US effects on chemical structures of bioactive compounds extracted from herbs and their bioactivities. The impact of different US processing conditions such as frequency, intensity, duration, temperature, and pressure on the effectiveness of the extraction process and the properties of the extracted materials are also discussed. Different frequencies and intensities of US have demonstrated its potential applications in modifying, determining, and predicting the physicochemical properties of herbs and their extracts. US has important applications in nanotechnology where it supports the fabrication of inexpensive and eco-friendly herbal nanostructures, as well as acoustic-based biosensors for chemical imaging of the herbal tissues. The application of US enhances the rates of chemical processes such as hydrolysis of herbal fibers, which reduces the time and energy consumed without affecting the quality of the final products. Overall, the use of US in herbal science has great potential to create novel chemical constructions and to be used as an innovative diagnostic system in various biomedical, food, and analytical applications.

Surface engineered iron oxide nanoparticles as efficient materials for antibiofilm application

Overuse of antibiotics has led to the development of multi drug resistant strains. Antibiotic resistance is a major drawback in the biomedical field since medical implants are prone to infection by biofilms of antibiotic resistant strains of bacteria. With increasing prevalence of antibiotic resistant pathogenic bacteria, the search for alternative method is utmost importance. In this regard, magnetic nanoparticles are commonly used as a substitute for antibiotics that can circumvent the problem of biofilms growth on the surface of biomedical implants. Iron oxide nanoparticles (IONPs) have unique magnetic properties that can be exploited in various ways in the biomedical applications. IONPs are engineered employing different methods to induce surface functionalization that include the use of polyethyleneimine and oleic acid. IONPs have a mechanical effect on biofilms when in presence of an external magnet. In this review, a detailed description of surface engineered magnetic nanoparticles as ideal antibacterial agents is provided, accompanied by various methods of literature review. This article is protected by copyright. All rights reserved.

Nanoparticle Beads of Chitosan-Ethylene Glycol Diglycidyl Ether/Fe for the Removal of Aldrin

This article reports on the preparation of iron nanoparticles (FeNPs) supported in chitosan beads (Chi-EDGE-Fe) for removing aldrin from aqueous solutions. The FeNPs and Chi-EDGE-Fe beads were characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and the Mössbauer spectroscopy (MS) techniques. TEM, XRD, and MS showed that the FeNPs had core-shell structures consisting of a core of either Fe0 or Fe2B and a shell of magnetite. Furthermore, SEM images showed that Chi-EDGE-Fe beads were spherical with irregular surfaces and certain degrees of roughness and porosity, whilst the sorbent mean pore size was 204 nm, and the occluded iron nanoparticles in the chitosan material had diameters of 70 nm and formed agglomerates. The sorbent beads consisted of carbon, oxygen, chlorine, aluminum, silicon, and iron according to the SEM-EDS analysis. Functional groups such as O-H, C-H, -CH2, N-H, C-O, C-OH, and Fe-OH were detected in the FTIR spectra. In addition, a characteristic band appeared at about 1700 cm−1 after the sorption process involving aldrin. MS also showed that the iron nanoparticles in the beads probably oxidized into NPs of α-Fe2O3 as a result of the supporting process. The isotherm of the aldrin removal followed the Langmuir–Freundlich model and presented a maximum adsorption capacity of 74.84 mg/g, demonstrating that chitosan-Fe beads are promising sorbents for the removal of toxic pollutants in aqueous solutions.

Green synthesis and environmental application of iron-based nanomaterials and nanocomposite: A review

Green chemistry has been proven to be an efficient route for nanoparticle synthesis. Plant extract based green synthesis of various nanoparticles is extensively studied since the last decade. This paper "Green synthesis and environmental application of Iron-based nanomaterials and nanocomposite: A review" unveils all the possible greener techniques for the synthesis of iron-based nanoparticles and nanocomposites. The use of different plant sources, microorganisms, and various biocompatible green reagents such as biopolymers, cellulose, haemoglobin, and glucose for the synthesis of iron nanoparticles reported in the last decade are summarized. The microwave method, along with hydrothermal synthesis due to their lower energy consumption are also been referred to as a green route. Apart from different plant parts, waste leaves and roots used for the synthesis of iron nanoparticles are extensively briefed here. This review is thus compact in nature which covers all the broad areas of green synthesis of iron nanoparticles (NPs) and iron-based nanocomposites. Detailed discussion on environmental applications of the various green synthesized iron NPs and their composites with performance efficiency is provided in this review article. The advantages of bimetallic iron-based nanocomposites over iron NPs in various environmental applications are discussed in detail. The hazards and toxic properties of green synthesized iron-based NPs are compared with those obtained from chemical methods. The prospects and challenges section of this article provides a vivid outlook of adapting such useful technique into a more versatile process with certain inclusions which may encourage and provide a new direction to future research.

Synthesis and Characterization of Magnetic Nanomaterials with Adsorptive Properties of Arsenic Ions

A new synthesis method of hybrid Fe₃O₄/C/TiO₂ structures was developed using microwave-assisted coprecipitation. The aim of the study was to examine the effect of the addition of glucose and titanium dioxide on adsorptive properties enabling removal of arsenic ions from the solution. The study involved the synthesis of pure magnetite, magnetite modified with glucose and magnetite modified with glucose and titanium dioxide in magnetite: glucose: titanium dioxide molar ratio 1:0.2:3. Materials were characterized by XRD, FT-IR, and BET methods. Magnetite and titanium dioxide nanoparticles were below 20 nm in size in obtained structures. The specific surface area of pure magnetite was approximately 79 m²/g while that of magnetite modified with titanium dioxide was above 190 m²/g. Obtained materials were examined as adsorbents used for removal As(V) ions from aqueous solutions. Adsorption of arsenic ions by pure magnetite and magnetite modified with titanium dioxide was very high, above 90% (initial concentration 10 mg/L), pH in the range from 2 to 7. The preparation of magnetic adsorbents with a high adsorption capacity of As(V) ions was developed (in the range from 19.34 to 11.83 mg/g). Magnetic properties enable the easy separation of an adsorbent from a solution, following adsorption.

Evolution of structural and magnetic properties in iron oxide nanoparticles synthesized using Azadirachta indica leaf extract

The novel superparamagnetic nature of magnetic nanoparticles (MNPs) has received significant attention in the wide variety of fields. However, the prerequisites to use these MNPs, particularly in biomedical applications are biocompatibility and high saturation magnetization (Ms). Thus, the development of a sustainable approach for the synthesis of biocompatible MNPs, which utilizes the redox properties of natural compounds from plant extracts, is highly desired. Herein, we have examined the growth of phase selective MNPs synthesized using Azadirachta indica (Neem) extract as a reducing and capping agent. The physical and biological properties of MNPs synthesized with the modified green hydrothermal method at different reaction times and temperatures were investigated. It was observed that the reaction time and temperature strongly modulated the magnetic and structural characteristics of MNPs. At lower reaction time and temperature of 200 °C for 2 h, primarily iron oxalate hydrate (Fe(C2O4).2(H2O)) was formed. Further, with increasing reaction temperature, the phase transformation from iron oxalate hydrate to pure magnetite (Fe3O4) phase was observed. The MNPs prepared with optimum conditions of 220 °C for 4 h show superparamagnetic nature with improved Ms value of 58 emu g−1. The antibacterial study of MNPs against gram-positive bacteria Staphylococcus aureus showed that the MNPs inhibits the growth of bacteria with the least inhibitory MNPs concentration of 6 μl. Thus, the MNPs obtained by this modified biogenic approach will widen the scope and their applicability in future biomedical applications.

Ultrasound assisted-phytofabricated Fe3O4 NPs with antioxidant properties and antibacterial effects on growth, biofilm formation, and spreading ability of multidrug resistant bacteria

Complicated issue in infectious illnesses therapy is increasing of multidrug resistant (MDR) bacteria and biofilms in bacterial infections. In this way, emerging of nanotechnology as a new weapon specifically in the cases of metal nanoparticle (MNPs) synthesis and MNPs surface modification has obtained more attention. In this study, ultrasound-assisted green synthesis method was utilized for the preparation of Fe₃O₄ NPs with novel shape (dendrimer) through leaf aqueous extract of Artemisia haussknechtii Boiss. Ultraviolet-visible spectroscopy, energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), atomic force microscopic (AFM), X-ray diffraction (XRD) techniques were applied for MNPs physicochemical characterization. Also, disc diffusion assay, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), planktonic and biofilm morphology of three pathogenic bacteria involving Serratia marcescens ATCC 13880, Escherichia coli ATCC 25922, and methicillin-resistant Staphylococcus aureus (MRSA) were evaluated upon treatment of Fe₃O₄ NPs as antiplanktonic and antibiofilm analysis. Results showed efficient antiplanktonic and antibiofilm activities of biosynthesized Fe₃O₄ NPs with average diameter size of 83.4 nm. Reduction in biofilm formation of S. aureus ATCC under Fe₃O₄ NPs stress was significant (66%) in higher MNPs concentration (100 μg/mL). In addition, as first report, spreading ability of S. aureus as important factor in colony expansion on culture medium was reduced by increasing of Fe₃O₄ NPs. Present study demonstrates striking antiplanktonic, antibiofilm, antispreading mobility and antioxidant aspects of one-pot biosynthesized Fe₃O₄ NPs with novel shape.

Green synthesis of metal oxide nanostructures using naturally occurring compounds for energy, environmental, and bio-related applications

This review summarizes the synthesis and functional applications of metal oxide nanostructures synthesized using plant-derived phytochemicals for energy, environmental, and biomedical applications.

Ultrasonic assisted green synthesis of Fe and Fe/Zn bimetallic nanoparticles for invitro cytotoxicity study against HeLa cancer cell line

Nanomaterial synthesis for the biomedical application is the latest improvement in nanotechnology. These nanomaterials can be used as therapeutic agent, drug carrier and also as activating agents. When the nanoparticles are prepared from biological sources, they show better medical competence with fewer side effects. Iron and zinc oxide nanoparticle have been found to exhibit good antimicrobial property; hence this bimetallic nanoparticle can be used for biomedical applications. Therefore the present work focused on synthesis of iron oxide and Fe/Zn bimetallic nano particle by Coriandrum sativum leaf extract as reducing agent using ultrasonic assisted method. The UV-Vis spectroscopy was used to confirm the synthesized nanoparticle. The crystallinity and shape of the particle formed was confirmed by XRD and SEM. The HeLa cell line and normal cell line were used to find the invitro cytotoxic activity of iron oxide and Fe/Zn bimetallic nanoparticle. Fe/Zn bimetallic nanoparticle and Iron oxide nanoparticle showed 61.96% and 54.95% cytotoxicity at 200 µg/ml concentration respectively against HeLa cancer cell line.