Synthesis Of Magnetite Nanoparticles Research Articles

Biosynthesis and recycling of magnetite nanocatalysts from Fe-rich sludge

Iron salts are widely used in municipal infrastructure to treat drinking water, prevent the corrosion of sewer lines and enhance phosphorus/nitrogen removal. The added iron salts deposit in sludge, leading to an increase in the cost of sludge disposal. Here, we demonstrated the feasibility of recycling magnetite nanoparticles (MNPs) produced from Fe-rich sludge under anaerobic conditions with indigenous microorganisms. The genus Geobacter was found to play the primary role in MNP synthesis. The produced MNPs were spherical with a size ranging from 12 to 24 nm. Compared to commercialized MNPs, the extracellular polysaccharides protected their surficial Fe2+ from being oxidized. The biosynthesized MNPs had a catalytic performance similar to that of commercialized MNPs but with high reusability after multiple cycles. These results demonstrate that the biosynthesis of MNPs is a novel and applicable way to recycle value-added products from Fe-rich sludge.

Effect of pH and Dye Concentration on the Photocatalytic Efficiency of Fe3O4 Nanoparticles Synthesized via Greener Route using Commiphora berryi and its Antibacterial Activity against Staphylococcus aureus and Escherichia coli

Green synthesis of magnetite nanoparticles is extremely developing methodology because of its bio compatibility nature. In the present work, iron oxide nanoparticles (IONPs) were synthesized by simple Co-precipitation method with the use of Commiphora berryi plant exudates. The formed iron oxide nanoparticles were characterized by FTIR, XRD and SEM techniques. Photocatalytic activity of synthesized iron oxide nanoparticles was determined against Methylene blue (MB) dye in aqueous medium. Iron oxide nanoparticles acted as a photocatalyst and decompose the dye under solar irradiation. Results show that 73 % of degradation efficiency was attained after 150 minutes with a nanoparticle dosage 0.5 mg/L which makes the IONPs as potential applicant for various effluent treatment methods. Further the results indicate that the efficiency increases with increasing pH and decrease with increasing the MB dye dosage. Antimicrobial activity of IONPS was studied against E.coli and S. aureus. IONPs show excellent antibacterial activity for both the organisms; with 16.5 mm and 16.75 mm zone of inhibition respectively for E.coli and S. aureus.

Antifungal Potential of Green Synthesized Magnetite Nanoparticles Black Coffee-Magnetite Nanoparticles Against Wilt Infection by Ameliorating Enzymatic Activity and Gene Expression in Solanum lycopersicum L.

Tomato plants are prone to various biotic and abiotic stresses. Fusarium wilt is one of the most devasting diseases of tomatoes caused by Fusarium oxysporum f. sp. lycopersici, causing high yield and economic losses annually. Magnetite nanoparticles (Fe3O4 NPs) are one of the potent candidates to inhibit fungal infection by improving plant growth parameters. Spinach has been used as a starting material to synthesize green-synthesized iron oxide nanoparticles (IONPs). Various extracts, i.e., pomegranate juice, white vinegar, pomegranate peel, black coffee (BC), aloe vera peel, and aspirin, had been used as reducing/stabilizing agents to tune the properties of the Fe3O4 NPs. After utilizing spinach as a precursor and BC as a reducing agent, the X-ray diffraction (XRD) pattern showed cubic magnetite (Fe3O4) phase. Spherical-shaped nanoparticles (∼20 nm) with superparamagnetic nature indicated by scanning electron microscopy (SEM) monographs, whereas energy-dispersive X-ray gives good elemental composition in Fe3O4 NPs. A characteristic band of Fe-O at ∼ 561 cm–1 was exhibited by the Fourier transform infrared (FTIR) spectrum. X-ray photoelectron spectroscopy (XPS) results confirmed the binding energies of Fe 2p3/2 (∼710.9 eV) and Fe 2p1/2 (∼724.5 eV) while, Raman bands at ∼310 cm–1 (T2 g), ∼550 cm–1 (T2 g), and 670 cm–1 (A1 g) indicated the formation of Fe3O4 NPs synthesized using BC extract. The in vitro activity of BC-Fe3O4 NPs significantly inhibited the mycelial growth of F. oxysporum both at the third and seventh day after incubation, in a dose-dependent manner. In vivo studies also exhibited a substantial reduction in disease severity and incidence by improving plant growth parameters after treatment with different concentrations of BC-Fe3O4 NPs. The increasing tendency in enzymatic activities had been measured after treatment with different concentrations of NPs both in roots and shoot of tomato plants as compared to the control. Correspondingly, the upregulation of PR-proteins and defense genes are in line with the results of the enzymatic activities. The outcome of the present findings suggests that Fe3O4 NPs has the potential to control wilt infection by enhancing plant growth. Hence, Fe3O4 NPs, being non-phytotoxic, have impending scope in the agriculture sector to attain higher yield by managing plant diseases.

Magnetite nanoparticles synthesized using grape fruit extract: synthesis, morphology, hyperthermia application and catalytic activity in hydrogen peroxide decomposition

The paper presents a simple one-step "green" approach to the synthesis of magnetite nanoparticles. The magnetite nanoparticles were synthesized using fruit extract obtained from grape peels and grape pulp. The formation of magnetite nanoparticles was confirmed by X-ray diffraction analysis (XRD), infrared spectroscopy (IR), Mössbauer spectroscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The crystallites sizes of magnetite nanoparticles are 7 and 14 nm for Fe3O4-peel and Fe3O4-pulp samples, respectively. Scanning electron microscopy images show that the samples consist of agglomerated nanoparticles. The synthesized magnetite nanoparticles showed good prospects for their use in magnetic hyperthermia. SAR values ​​of 0.488 W/g and 1.330 W/g for Fe3O4-peel and Fe3O4-pulp samples, respectively. The synthesized magnetic nanoparticles show excellent colloidal stability in the aqueous solutions. The maximum hyperthermia temperatures are 42.28 °C and 42.48 °C for Fe3O4-peel and Fe3O4-pulp samples, respectively. Studies of the catalytic activity of magnetite were performed in decomposition of hydrogen peroxide in a batch mode. The degrees of H2O2 decomposition are 67.5% and 65.25% for the Fe3O4-peel and Fe3O4-pulp samples respectively. The high catalytic activity of the synthesized samples makes them promising candidates for the decomposition of hydrogen peroxide in wastewater disinfection.

Polymeric Composite of Magnetite Iron Oxide Nanoparticles and Their Application in Biomedicine: A Review.

A broad spectrum of nanomaterials has been investigated for multiple purposes in recent years. Some of these studied materials are magnetics nanoparticles (MNPs). Iron oxide nanoparticles (IONPs) and superparamagnetic iron oxide nanoparticles (SPIONs) are MNPs that have received extensive attention because of their physicochemical and magnetic properties and their ease of combination with organic or inorganic compounds. Furthermore, the arresting of these MNPs into a cross-linked matrix known as hydrogel has attracted significant interest in the biomedical field. Commonly, MNPs act as a reinforcing material for the polymer matrix. In the present review, several methods, such as co-precipitation, polyol, hydrothermal, microemulsion, and sol-gel methods, are reported to synthesize magnetite nanoparticles with controllable physical and chemical properties that suit the required application. Due to the potential of magnetite-based nanocomposites, specifically in hydrogels, processing methods, including physical blending, in situ precipitation, and grafting methods, are introduced. Moreover, the most common characterization techniques employed to study MNPs and magnetic gel are discussed.

Review Article: Synthesis of Fe3O4 Nanoparticle and Its Application for Glassy Carbon Electrode Modification

Nanomaterials have various unique properties and characteristics so that they can apply in many sectors. One of the most popular nanoparticles today is magnetite nanoparticles. Magnetite particles have several properties such as being super magnetic, having a high saturation field, chemical stability, biocompatibility, and low production costs. The purpose of this article is to review the synthesis of magnetite nanoparticles and their application to Glassy Carbon Electrode (GCE) modification. This modified GCE can applied as an electrochemical sensor to detect various organic and inorganic substances. In this study, type synthesis methods of magnetite nanoparticles which taken from kind literature well investigation include coprecipitation, sol-gel, microemulsion, hydrothermal, and thermal decomposition. The five routes have their respective advantages and disadvantages. Then the nano magnetite made can applied to modify the GCE as an electrochemical sensor that can detect uric acid, bacteria, and even metals dissolved in water.

Facile controllable synthesis of magnetite nanoparticles via a co-precipitation approach

Facile controllable synthesis of magnetite nanoparticles via a co-precipitation approach

A single rapid route synthesis of magnetite/chitosan nanocomposite: Competitive study

At last decides, the modification of synthesis protocol towards shorter reaction time, fewer steps, and lower resources cost was needed. The synthesis of magnetite (Fe3O4) polymer nanocomposite is heavily studied nowadays due to its promising applications. In this study, magnetite chitosan nanocomposite was synthesized through two competitive routes; a new single route synthesis based on co-precipitation at hydrothermal conditions, and the second route a conventional multi-synthetic route based on using the blending solution method after magnetite nanoparticles synthesis by the co-precipitation method of magnetite. The synthesized Fe3O4 and its nanocomposites are characterized by several techniques, including Fourier transition infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibration sample magnetometer (VSM). The results showed magnetite polymer nanocomposite synthesized via a single synthetic route had less particle size, more distribution in the chitosan matrix, and higher magnetization saturation than that synthesized via a multi-synthetic route. Adsorption of Rodamine 6G dye on magnetite chitosan nanocomposite was studied in different parameters. The adsorption results showed a rapid process following the Tempkin isotherm.

Review on Plant Mediated Green Synthesis of Magnetite Nanoparticles for Pollution Abatement, Biomedical and Electronic Applications

In nature, the iron oxide is found in various forms. It is chemically mixed to form iron oxides (compounds). Magnetite has helpful uses in different areas, such as medicinal carriers, MRI-contracting agents, tumour therapies, industrial, laboratory dyes adsorption and wastewater treatment of toxic metals such as mercury and arsenic. Magnetic iron oxide nanoparticles are generated using various methods such as wet, dry or microbiological processes. The drawbacks of conventional nanoparticles including attrition and pyrolysis include a defective surface formation, poor efficiency rates, high development costs and high energy consumption. The first approach is the green biosynthesis of the nanoparticles in which the metal atoms are clusters. The organic compounds can both minimize and cover nanoparticles in the process of synthesis in green materials. In recent years, nanocarriers, especially for poorly soluble medicines, have received growing attention for oral chemotherapy. Early disease bacteria, biopsy, cells, DNA, glucose and viruses are identified by biosensing. While several basic characteristics have different advantages and potential for biomedical use of magnets of iron oxides, more toxicological research is required on as-synthesized magnet iron oxide nanoparticles with clearly defined requirements for toxicity assessment.

Optimization by Box–Behnken Design and Synthesis of Magnetite Nanoparticles for Removal of the Antibiotic from an Aqueous Phase

Some environmental problems caused by the intrusion of active drug ingredients, especially antibiotics, into water resources pose a serious threat. Ciprofloxacin (CIP) is an antibiotic from the group of fluoroquinolones that is used extensively in the treatment of bacterial infections. The presence of drug residues in the environment, especially in water resources, is an essential issue due to their stability and nondegradability. This study is aimed at investigating the efficiency of magnetite (Fe3O4) nanoparticles and the effect of independent variables, including initial concentrations of CIP (35-80 mg/L), adsorbent doses (20–60 mg), and pH values (4–10) at reaction time (80 min) for the removal efficiency of CIP antibiotics based on the Box-Behnken design (BBD) method. The analysis of variance (ANOVA) results indicated that a quadratic model was convenient for modeling CIP removal. The first step, the coprecipitation method, was appropriate for the preparation of Fe3O4 nanoparticles and developed as highly efficient adsorbents. Synthesized nanoparticles were later characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and Fourier transform infrared spectra (FT-IR). The results of XRD have shown that angles for the peaks at [Formula: see text], which corresponded to the crystal planes 220, 311, 400, 422, 511, 440, and 535, respectively, were consistent with standard peaks of magnetite and a cubic face structure. The obtained results indicated that the CIP removal efficiency was 74.44% under optimum operation parameters: initial concentration of CIP 44.15 (mg/L), adsorbent dosage of 59.6 (mg), [Formula: see text], and contact time of 80 min. In fact, a cooperative agreement between model prediction and experimental data using BBD with significant [Formula: see text] values of 0.95 was observed. Based on the results, magnetite nanoparticles have an excellent ability to remove antibiotics from an aqueous phase.

Biogenic Synthesis of Magnetite Nanoparticles Using Leaf Extract of Thymus schimperi and Their Application for Monocomponent Removal of Chromium and Mercury Ions from Aqueous Solution

Currently, plant templated synthesis of magnetite iron oxide nanoparticles (Fe3O4 NPs) was emerged for multifunctional purposes. In this study, the leaf extract of the plant Thymus schimperi was utilized to synthesize Fe3O4 NPs. The synthesized NPs were characterized by using technical tools such as X‐ray diffraction (XRD) spectroscopy, Fourier transform infrared (FT‐IR) spectroscopy, scanning electron microscopy‐energy dispersive X‐ray (SEM‐EDX) analysis, and ultraviolet‐visible (UV‐Vis) spectroscopy, and thermal analysis (TGA‐DTA). The XRD result corroborated the presence of desired phase formation having pure cubic face centered phase structure with average crystallite particle size ranging from 20 nm to 30 nm. SEM micrographs confirmed microstructural homogeneities and remarkably different morphology of Fe3O4 NPs. Mercury (II) and chromium (VI) removal efficiencies of Fe3O4 NPs were found to be 90% and 86% from aqueous solution at initial concentration of 20 mg/L, respectively. Various factors which affect the metal ion removal efficiency such as metal ion initial concentrations, pH, contact time, and adsorbent dosage were also studied. The optimum pH and contact time for chromium ion adsorption were pH 5 and 60 min and that of mercury were observed to be pH 7 and 90 min, respectively. The Langmuir isotherm was best fitted for sorption of Hg(II) ion, and the Freundlich isotherm was best fitted with sorption of Cr(VI) ion onto the surface of Fe3O4 NPs. The mechanism of adsorption of both Hg(II) and Cr(VI) ions was obeyed pseudo 2nd order kinetics. The recorded percent removal efficiencies revealed that these Fe3O4 NPs synthesized through leaf extract of the plant called Thymus schimperi have demonstrated excellent potentiality in the remediation of heavy metal ions. The synthesized Fe3O4 NPs were regenerated (reused) for adsorptive removal of Hg(II) and Cr(VI) for five consecutive cycles without significant loss of removal efficiency. Fe3O4 NPs were reused with only 4.17% loss of removal efficiency against Hg(II) and only 3% loss of removal efficiency against Cr(VI) metal ions.

A novel study on the preferential attachment of chromophore and auxochrome groups in azo dye adsorption on different greenly synthesized magnetite nanoparticles: investigation of the influence of the mediating plant extract's acidity.

In this paper, the adsorption of Evans blue (EB) and methyl orange (MO) azo dyes on four greenly synthesized magnetite nanoparticles has been studied to investigate the effect of the mediating plant extract's acidity on magnetite surface reactivity in azo dye adsorption. Magnetite surface reactivity has been studied through the analysis of preferential attachment of dye chromophore and auxochrome groups on magnetite nanoparticles, and adsorption yields. According to the contents of chromophore and auxochrome groups in dye structures, the mediating plant extract's acidity effect on acid site types and densities was also deduced. Used plants for the green synthesis were: Artemisia herba-alba (L), Matricaria pubescens (L), Juniperus phoenicea (L), and Rosmarinus officinalis (L), and their extract pHs were respectively 5.25, 5.05, 4.63, and 3.69. The four greenly synthesized samples of magnetite were characterized by XRD, SEM, ATR-FTIR, and UV-Vis techniques. The novelty of this paper lies in highlighting the influence of the mediating plant extract's acidity on the greenly synthesized magnetite surface reactivity towards the preferential attachment of chromophore and auxochrome functional groups in azo dye adsorption, where obtained results show that the mediating plant extract's acidity has a clear effect on the preferential attachment of chromophore and auxochrome groups on magnetite surfaces as well as on azo dyes' adsorption yields and capacities. Indeed, the decrease in the plant extract's acidity leads to an increase in the attachment of chromophore groups and a decrease in the attachment of auxochrome groups. So, it leads to an increase in Lewis acid site density and a decrease in Brønsted acid site density of magnetite surfaces. Also, the decrease of the plant extract's acidity leads to an increase in the studied dye adsorption yields, and this is because the majority of functional groups of MO and EB dyes are chromophores that attach to Lewis acid sites. The difference found in adsorption yields of EB and MO on all four magnetite samples is due to the fact that the ratio of chromophore/auxochrome groups in EB is remarkably greater than that in MO. The linear and non-linear pseudo-first-order and pseudo-second-order kinetics of the adsorption as well as the intra-particle diffusion mechanism have been analyzed. Obtained results indicate that in all adsorption processes the adsorption kinetics followed a linear pseudo-first-order kinetic model, and film diffusion is the step that controlled adsorption mechanisms. The thermodynamic studies of EB and MO adsorption processes on the four magnetite surfaces have been analyzed in the temperature range of 303.15–318.15 K. Obtained results reveal the endothermic nature of the adsorption in all cases.

Preferential and enhanced adsorption of methyl green on different greenly synthesized magnetite nanoparticles: investigation of the influence of the mediating plant extract's acidity.

Four magnetite nanoparticle (NP) samples have been greenly synthesized using four aqueous plant extracts, which are Artemisia herba-alba (L), Rosmarinus officinalis (L), Matricaria pubescens (L), and Juniperus phoenicia (L). The pH of these extracts are acidic (5.25, 5.05, 4.63, and 3.69, respectively). The synthesized samples were characterized by XRD, SEM, ATR-FTIR, and UV-Vis. This work aimed to study the preferential and enhanced adsorption of methyl green (MG) on the four greenly synthesized Fe3O4 surfaces by coupling three processes: MG adsorption in ambient dark conditions as the first process, followed by the thermocatalysis of the MG/Fe3O4 residual solution in the second process, and finally photocatalysis by the UV irradiation of MG/Fe3O4 residual solution after carrying out thermocatalysis. The novelty of this study lies in highlighting the influence of the mediating plant extract’s acidity on the magnetite NPs’ physicochemical characteristics, which impact the preferential and enhanced MG adsorption. The studied physicochemical characteristics are the functional hydroxyl group density on the magnetite surface, grain size, and band gap energy. It was found that the plant extract’s acidity has a clear effect on the studied physicochemical properties. The analysis of the FTIR spectra showed that the hydroxyl group densities differ on the four magnetite samples. Furthermore, the calculated grain sizes of the magnetite samples based on XRD spectra data vary from 29.27 to 41.49 nm. The analysis of the UV-Vis spectra of the four magnetite samples showed that the estimated direct band gap energies vary from 2.87 to 2.97 eV. The obtained results showed that the decrease of the mediating plant extract’s acidity leads to an increase in the hydroxyl group density on magnetite surfaces, which resulted in an increase in the MG adsorption capacities and yields in the first process of adsorption. Thus, MG adsorption was more preferred on greenly synthesized magnetite surfaces mediated by plant extracts with low acidity (Artemisia herba-alba (L) and Rosmarinus officinalis (L)). Furthermore, the increase of the plant extract’s acidity leads to a decrease in the particle size and an increase in the band gap energy and, therefore, to the decrease of the electron/hole pair recombination speed upon electron excitation. So, magnetite greenly synthesized from a more acidic mediating plant extract showed higher thermo- and photocatalytic activities for MG adsorption (Juniperus phoenicia (L) and Matricaria pubescens (L)). However, under photocatalysis, the enhancement is even more significant compared to thermocatalysis.

Reaction Mechanisms of the Electrosynthesis of Magnetite Nanoparticles Studied by Electrochemical Impedance Spectroscopy.

This work presents a mechanistic study of the electrochemical synthesis of magnetite nanoparticles (NPs) based on the analysis of the electrochemical impedance spectroscopy (EIS) technique. After a discussion of the mechanisms reported in the literature, three models are devised and a prediction of their EIS spectra is presented. The approach consisted of the simulation of EIS spectra as a tool for assessing model validity, as EIS allows to characterize the relaxation of adsorbed intermediates. The comparison between the simulated impedance spectra and the experimental results shows that the mechanisms proposed to date do not explain all of the experimental results. Thus, a new model is proposed, in which up to three adsorbed intermediate species are involved. This model accounts for the number of loops found in experimental impedance data. The closest approximation of the features found in the experimental spectra by this proposed model suggests a better representation of the reaction mechanism within the evaluated potential range.

Magnetic properties of iron oxide nanoparticles with a DMSA-modified surface

The magnetic properties of magnetite nanoparticles (Fe3O4 NPs) strongly depend on their chemical and physical parameters, which can be regulated by a controlled synthesis process. To improve the quality of the obtained nanoparticles, their surface is often modified with organic compounds (from the group of surfactants, sugars, proteins, or organic acid). In this study, we synthesized magnetite nanoparticles with a surface modified with the organic compound DMSA. Then, the nanocrystallites were characterized in terms of structure and morphology. To investigate the role of DMSA and to understand the adsorption mechanism, FTIR measurements were carried out. Using Mössbauer spectroscopy, we investigated temperature-induced changes in the magnetic properties of prepared samples. The spectra were recorded in a wide temperature range (from 4 K to 390 K) for two types of samples: powders and ferrofluids with various concentrations. In the case of powder samples, the superparamagnetic doublet appeared at room temperature. For magnetic suspensions, the spectra were more complicated. They consisted of superposition of asymmetrically broadened sextets and doublets, which was caused by the occurrence of long-range dipole-dipole interactions. These interactions affected the magnetic properties of the material and increased the blocking temperature. Additionally, the magnetic hysteresis and zero field cooling-field cooling (ZFC/FC) curves were measured with the use of a vibrating sample magnetometer.

Green synthesis of magnetite nanoparticles (Fe3O4 NPs) using Acacia concinna fruit extract and their antibacterial activity

AbstractThis paper describes green, simple, and efficient method for the synthesis of magnetite nanoparticles (Fe3O4 NPs) using Acacia concinna fruit extract for the first time. A. concinna fruit extract is used as reducing and stabilizing agent. Reduction of Fe3+ ions by A. concinna fruit extract is examined by UV‐visible absorption spectra (UV‐Vis‐NIR). To recognize the functional group responsible for Fe3O4, the NPs are characterized by Fourier transform infra‐red spectroscopy (FTIR). The structural analysis of Fe3O4 NPs is done by X‐ray diffraction (XRD) which confirms cubic spinel structure and the average crystallite size of obtained NPs is found to be 28 nm. The morphological studies of Fe3O4 NPs are done by scanning electron microscope (SEM) which depicts the quasi‐spherical morphology. The green synthesized Fe3O4 NPs shows distinctive antibacterial activities against gram‐negative E. coli and Pseudomonas aeruginosa microorganism which confirms its potential in biomedical applications.

Fe3O4 Nanoparticles: Structures, Synthesis, Magnetic Properties, Surface Functionalization, and Emerging Applications.

Magnetite (Fe3O4) nanoparticles (NPs) are attractive nanomaterials in the field of material science, chemistry, and physics because of their valuable properties, such as soft ferromagnetism, half-metallicity, and biocompatibility. Various structures of Fe3O4 NPs with different sizes, geometries, and nanoarchitectures have been synthesized, and the related properties have been studied with targets in multiple fields of applications, including biomedical devices, electronic devices, environmental solutions, and energy applications. Tailoring the sizes, geometries, magnetic properties, and functionalities is an important task that determines the performance of Fe3O4 NPs in many applications. Therefore, this review focuses on the crucial aspects of Fe3O4 NPs, including structures, synthesis, magnetic properties, and strategies for functionalization, which jointly determine the application performance of various Fe3O4 NP-based systems. We first summarize the recent advances in the synthesis of magnetite NPs with different sizes, morphologies, and magnetic properties. We also highlight the importance of synthetic factors in controlling the structures and properties of NPs, such as the uniformity of sizes, morphology, surfaces, and magnetic properties. Moreover, emerging applications using Fe3O4 NPs and their functionalized nanostructures are also highlighted with a focus on applications in biomedical technologies, biosensing, environmental remedies for water treatment, and energy storage and conversion devices.

Modification of Magnetite Nanoparticles with Triazine-Based Dendrons and Their Application as Drug-Transporting Systems.

The following research aims at the synthesis of magnetite nanoparticles functionalized with triazine-based dendrons and the application of the obtained materials as effective sorptive materials dedicated to acidic bioactive compounds. The adopted synthetic approach involved: (1) the synthesis of nanosized Fe3O4 particles via classic co-precipitation method, (2) the introduction of amine groups on their surface leading to materials’ precursor, and (3) the final synthesis of branched triazine-based dendrons on the support surface by an iterative reaction between cyanuric chloride (CC) and piperazine (p) or diethylenetriamine (DETA) via nucleophilic substitution. The characterized materials were tested for their adsorptive properties towards folic acid, 18β–glycyrrhetinic acid, and vancomycin, showing high adsorption capacities varying in the ranges of 53.33–401.61, 75.82–223.71, and 68.17–132.45 mg g−1, respectively. The formed material–drug complexes were also characterized for the drug-delivery potential, performed as in vitro release studies at pH 2.0 and 7.4, which mimics the physiological conditions. The release profiles showed that the proposed materials are able to deliver up to 95.2% of the drugs within 48 h, which makes them efficient candidates for further biomedical applications.

Biodecolorization of reactive black 5 using magnetite nanoparticles coated Bacillus sp. RA5

Azo dyes are extensively used in various industrial sectors and their release into the surrounding contributes to the environmental pollution. In the present study, the bacterial cells coated with chemically synthesized magnetite nanoparticles were utilized for the biodecolorization of azo dye, reactive black 5 (RB5). The decolorization potential of immobilized cells was also compared with the free cells. At optimum experimental conditions, the complete dye removal was observed at 18 h by free cells whereas nanoparticle coated cells showed complete decolorization at 24 h for 100 ppm of RB5 dye concentration. UV–Vis spectroscopy and Fourier Transform Infrared Spectroscopy analysis of dye samples, before and after microbial treatment, confirmed the dye decolorization. The coated bacterial cells were able to decolorize the dye, efficiently, up to 12 cycles, confirming the reusability, stability and recyclability of magnetite coated bacterial cells.

Synthesis of Magnetite Nanoparticles through a Lab-On-Chip Device.

Magnetite nanoparticles (MNPs) represent one of the most intensively studied types of iron oxide nanoparticles in various fields, including biomedicine, pharmaceutics, bioengineering, and industry. Since their properties in terms of size, shape, and surface charge significantly affects their efficiency towards the envisaged application, it is fundamentally important to develop a new synthesis route that allows for the control and modulation of the nanoparticle features. In this context, the aim of the present study was to develop a new method for the synthesis of MNPs. Specifically, a microfluidic lab-on-chip (LoC) device was used to obtain MNPs with controlled properties. The study investigated the influence of iron precursor solution concentration and flowed onto the final properties of the nanomaterials. The synthesized MNPs were characterized in terms of size, morphology, structure, composition, and stability. Results proved the formation of magnetite as a single mineral phase. Moreover, the uniform spherical shape and narrow size distribution were demonstrated. Optimal characteristics regarding MNPs crystallinity, uniformity, and thermal stability were obtained at higher concentrations and lower flows. In this manner, the potential of the LoC device is a promising tool for the synthesis of nanomaterials by ensuring the necessary uniformity for all final applications.