Presence Of Magnetite Nanoparticles Research Articles

Magnetic functionalization and catalytic behavior of magnetic nanoparticles during laser photochemical graphitization of polyimide

We report laser-assisted photochemical graphitization of polyimides (PIs) into functional magnetic nanocomposites using laser irradiation of PI in the presence of magnetite nanoparticles (MNPs). PI Kapton sheets covered with MNP were photochemically treated under ambient conditions using a picosecond pulsed laser (1064 nm) to obtain an electrically conductive material. Scanning electron microscopy of the treated material revealed a layered magnetic nanoparticle/graphite (MNP/graphite) nanocomposite structure. Four probe conductivity measurements indicated that the nanocomposite has an electrical conductivity of 1550 ± 60 S/m. Superconducting quantum interference device magnetometer-based magnetic characterization of the treated material revealed an anisotropic ferromagnetic response in the MNP/graphite nanocomposite compared to the isotropic response of MNP. Raman spectroscopy of the MNP/graphite nanocomposite revealed a fourfold improvement in graphitization, suppression in disorder, and decreased nitrogenous impurities compared to the graphitic material obtained from laser treatment of just PI sheets. X-ray photoelectron spectroscopy, x-ray diffraction, and energy-dispersive x-ray spectroscopy were used to delineate the phase transformations of MNP during the formation of MNP/graphite nanocomposite. Post-mortem characterization indicates a possible photocatalytic effect of MNP during MNP/graphite nanocomposite formation. Under laser irradiation, MNP transformed from the initial Fe3O4 phase to γ-Fe2O3 and Fe5C2 phases and acted as nucleation spots to catalyze the graphitization process of PI.

Mechanically recyclable melt-spun fibers from lignin esters and iron oxide nanoparticles: towards circular lignin materials

Melt spinning of lignin C18 fatty acid esters in the presence of magnetite nanoparticles provides a facile and green way to magnetically responsive microfibers for water purification and more.

Influence of organic ligands on the stoichiometry of magnetite nanoparticles.

Magnetite, a ubiquitous mineral in natural systems, is of high interest for a variety of applications including environmental remediation, medicine, and catalysis. If the transformation of magnetite to maghemite through the oxidation of Fe2+ has been well documented, mechanisms involving dissolution processes of Fe2+ in aqueous solutions have been overlooked. Here, the effect of dissolved organic ligands (EDTA (ethylenediaminetetraacetic acid), acetic, lactic and citric acids) on Fe2+ solubility and on the stoichiometry (Fe(ii)/Fe(iii)) of magnetite-maghemite nanoparticles (∼10 nm) was investigated. These ligands were chosen because of their environmental relevance and because they are widely used as coating agents for nanotechnology applications. Results show an insignificant effect of 2 organic ligands (acetate and lactate) on the dissolution of Fe. By contrast, citrate and EDTA enhanced Fe solubility because of the formation of dissolved Fe(ii)- and Fe(iii)-ligand complexes. Both ligands selectively bound Fe(ii) over Fe(iii), but EDTA was much more selective than citrate. The combined effects of oxidation and H+- and ligand-promoted dissolution of Fe from magnetite were predicted using a magnetite-maghemite solid solution model, accounting for the formation of dissolved Fe(ii)- and Fe(iii)-ligand complexes. Therefore, these results show that citrate and EDTA (i) enhance Fe solubility in the presence of magnetite nanoparticles and (ii) modify magnetite stoichiometry, which affects its environmental behavior and its properties for nanotechnology applications.

Mechanical Properties of Lightweight Foamed Concrete Modified with Magnetite (Fe3O4) Nanoparticles

The advancement in sustainable construction has stimulated wide-ranging investigation of construction materials and practices globally. With exceptional thermal properties, fire resistance performance, excellent strength, and outstanding durability, concrete is the utmost extensively utilized construction material around the world. Taking into consideration the quantity of concrete necessary for numerous constructions works, improving concrete sustainability would be an extremely attractive potential. Lightweight foamed concrete (LFC) is tremendously permeable, and its mechanical properties weaken with a growth in the volume of voids. Air-void segregation from solid cement phases by means of aging, drainage, and merging of voids can trigger and reduce the stability and consistency of the emitted pores, making the LFC less reliable for main utilization in load-bearing components and structural elements. In turn, to augment LFC mechanical properties, the LFC cementitious matrix can be adjusted by adding various nanoparticles. The influence of magnetite nanoparticles (MNP) in LFC was not examined in the past; hence, there is some vagueness considering the mechanism to which level the MNP can affect the LFC mechanical properties. Thus, the aim of this study is to investigate the influences of MNP on the compressive, splitting tensile, and flexural LFC of 1000 kg/m3 density. Six MNP weight fractions of 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, and 0.35% were considered. The parameters accessed were compressive, splitting tensile and flexural strengths. The correlation between strength parameters was established as well. The results indicated that a 0.25% weight fraction of MNP gave the best performance in terms of compressive, flexural, and splitting tensile strengths. The presence of MNP in the LFC matrix enhances the viscosity and yield stress of the mixture as well as an augmented utilization of LFC cementitious binder content, which can sustain the integrity of the wet networks hence preventing further amalgamation and aging of the voids.

Viability and Colony Morphology Variation of Rhodococcus rhodochrous CNMN-Ac-05 in the Presence of Magnetite Nanoparticles

In recent decades the use of nanotechnologies in the remediation of xenobiotic substances has proven its effectiveness, but not its safety. Nanoparticles often accumulate in the remedied environment, having, over time, toxic effects on living organisms. In this context, research on the vital activity of microorganisms and their interaction with nanoparticles is of major importance. Aim of the research was to determine the influence of Fe3O4 nanoparticles, obtained by different ways (laboratory method and synthesis in the reactor) on the viability and colony morphology of Rhodococcus rhodochrous CNMN-Ac-05 strain. Methods. Encapsulated magnetite (Fe3O4) nanoparticles were synthesized by chemical co-precipitation method, using iron(II) sulfate and iron(III) chloride in the presence of poly-N-vinylpyrrolidone, used as a stabilizer. Fe3O4 SR (Synthesis in the Reactor) was produced in the multifunctional reactor VGR-50, at the same conditions. Cell biomass was determined on the spectrophotometer by the optical density at 540 nm,with subsequent recalculation to cell dry weight according to the calibration curve. The cell dry weight was determined by gravimetric method. The morphological features of the rhodococci colonies were described according to the standard microbiological method. Results. It was established that magnetite nanoparticles in concentrations of 1–100 mg/L were not toxic to the R. rhodochrous strain, had a positive effect on the viability of rhodococci by stimulating the growth of biomass, regardless of their concentration and the method of their synthesis. In the presence of Fe3O4 nanoparticles the population dissociated to S1, S2, R1, R2 forms, and S-R type of colonies, while the basic morphological features of R. rhodochrous colonies corresponded to type S1. Conclusions. The optimal concentration of magnetite nanoparticles, which stimulated the growth and development of R. rhodochrous was 25 mg/L for Fe3O4 and 50 mg/L Fe3O4 SR. At all concentration of Fe3O4 nanoparticles the main colony morphotype of the rhodococci was smooth S1-type; the new types of colonies represented only 0.1–0.6% of the population, and the lowest degree of variability corresponded with the highest colony-forming units index.

Separation and Tracing of Anthropogenic Magnetite Nanoparticles in the Urban Atmosphere.

Nanosized magnetite is a highly toxic material due to its strong ability to generate reactive oxygen species in vivo, and the presence of magnetite NPs in the brain has been linked with aging and neurodegenerative diseases such as Alzheimer's disease. Recently, magnetite pollution nanoparticles (NPs) were found to be present in the human brain, heart, and blood, which raises great concerns about the health risks of airborne magnetite NPs. Here, we report the abundant presence and chemical multifingerprints (including high-resolution structural and elemental fingerprints) of magnetite NPs in the urban atmosphere. We establish a methodology for high-efficiency retrieving and accurate quantification of airborne magnetite NPs. We report the occurrence levels (annual mean concentration 75.5 ± 33.2 ng m-3 in Beijing with clear season variations) and the pollution characteristics of airborne magnetite NPs. Based on the chemical multifingerprints of the NPs, we identify and estimate the contributions of the major emission sources for airborne magnetite NPs. We also give an assessment of human exposure risks of airborne magnetite NPs. Our findings support the identification of airborne magnetite NPs as a threat to human health.

Magnetically driven poly(sulfur/oil) composite as an efficient oil adsorbent. Part-I: Synthesis, characterization and preliminary oil removal study

In this work, magnetite loaded poly(sulfur/oil) (MLP(S/O)) composite super hydrophobic polymer has been prepared by allowing reaction between sulfur powder and edible oil in the presence of magnetite nano particles. The magnetite particles, with 68 % of the particles in the range of 5–10 nm, were characterized by TEM and SAED analysis. The MLP(S/O) material was also characterized by FTIR, XRD, TGA/DTA, EDS and SEM analysis. The M-H curves were also obtained for the adsorbent material MLP(S/O), taking native magnetite nanoparticles as control. It was found that the composite MLP(S/O) possessed fair magnetization. The saturation magnetization MS for the native magnetite and the MLP(S/O) composite were found to be 27.889 and 7.996 emu/g respectively. In addition, the Remanent Magnetization (MR), for the samples magnetite powder and MLP(S/O) composite were found to be 0.172 and 0.0199 emu/g respectively. Finally, the MLP(S/O) material was used as adsorbent to remove oil from water and the oil-adsorbed MLP(S/O) was removed from the adsorption system by using a bar magnet with moderate strength.

Arsenic Removal from Water by Green Synthesized Magnetic Nanoparticles

Magnetite nanoparticles were synthesized by a simple and ecofriendly method using onion peel (MNp-OP) and corn silk extract (MNp-CS), in order to develop new low-cost adsorbents for arsenic removal from groundwater. As a point of comparison, magnetite nanoparticles were also synthesized with a conventional chemical process (MNp-CO). The antioxidant potential of onion peel and corn silk extracts was determined using ferric reducing antioxidant power (FRAP) and free radical (DPPH) scavenging assays, including the total phenolics, flavonoids and tannins contents. The synthesized magnetite nanoparticles were characterised using different techniques (Scanning electron microscope/Energy dispersive spectroscopy (SEM/EDS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and Brunauer-Emmett-Teller (BET) surface area analyzer). The adsorption capacity of MNp-OP and MNp-CS and the arsenic removal mechanism of these novel adsorbents was investigated through kinetic and equilibrium experiments and their corresponding mathematical models. Characterisation of MNp-OP and MNp-CS shows high BET specific surface areas of 243 m2/g and 261 m2/g, respectively. XRD and FTIR analysis confirmed the formation and presence of magnetite nanoparticles. The arsenic adsorption mechanism on MNp-OP, MNp-CS and MNp-CO involves chemisorption, intraparticle and external diffusion. Maximal adsorption capacities of MNp-OP, MNp-CS and MNp-CO were 1.86, 2.79, and 1.30 mg/g respectively. The green synthesis applied using onion peel and corn silk extracts was cost effective and environmentally friendly, and results in adsorbents with a high capacity for arsenic and magnetic properties, making them a very promising alternative approach in the treatment of arsenic contaminated groundwater.

New magnetic polyurethane hybrid composite for oil sorption

ABSTRACTThe new polyurethane/cellulose acetate/magnetic iron oxide nanoparticles composites synthesised presented potential for use as sorbents of mineral oil. The composite synthesised in homogeneous medium in the presence of magnetite nanoparticles presented higher oil sorption capacity than composite synthesised in heterogeneous medium for all analysed conditions, and the values obtained, 9.6 ± 0.1 and 12.2 ± 0.5 grams of oil per gram of sorbent, wet and dry dynamic media, respectively, were comparable to those exhibited by commercial products. In addition, the magnetite facilitates the separation of the composite after the sorption process by external magnetic field.

Magnetite nanoparticles enhance the bioelectrochemical treatment of municipal sewage by facilitating the syntrophic oxidation of volatile fatty acids

AbstractBACKGROUNDMicrobial electrochemical technologies (METs) represent a novel platform to harvest the energy trapped in municipal wastewater. At the anode of METs, electro‐active bacteria (EAB) anaerobically oxidize wastewater constituents using the electrode as the terminal electron acceptor and, by so doing, generate an electric current. To convert complex wastewater constituents into electricity, EAB must not only establish syntrophic relationships with other members of the microbial community, but also compete with methanogens for consumption of hydrogen and acetate. Here, we examined the addition of magnetite nanoparticles (NPs) (250 mg Fe L−1) as a novel strategy to manipulate such metabolic interactions and in turn maximize the efficiency of wastewater treatment and the yield of electric current generation.RESULTSBatch experiments carried out either in the presence of a mixture of volatile fatty acids or of a synthetic sewage demonstrated that magnetite addition accelerate the rate of electrogenic oxidation of specific compounds, particularly propionate (up to 120%), an intermediate which frequently accumulates during anaerobic treatment processes, while correspondingly enhancing electric current generation (up to 90%), and diminishing the rate of competing methane generation (up to 50%). Notably, the composition of the microbial community was not substantially affected by the presence of magnetite nanoparticles, possibly suggesting that these latter facilitated extracellular electron transfer mechanisms (among microbes and with the electrode), rather than enriching conditions for specific microorganisms.CONCLUSIONThe addition of magnetite NPs may represent a practical strategy to kick‐start a bioelectrochemical system designed for wastewater treatment and improve the effectiveness of electrogenic substrate oxidation processes. © 2019 Society of Chemical Industry

Comparison study of Ag(I) and Au(III) loaded on magnetic thiourea-formaldehyde as disinfectants for water pathogenic microorganism’s deactivation

Magnetic disinfectants were achieved through the polymerization of thiourea and formaldahyde in the presence of magnetite nano particles (MTUF), the as-prepared MTUF was loaded with Ag(I) or Au(III). The obtained disinfectants (MTUF-Ag and MTUF-Au) were test for some selected pathogenic strains deactivation. The toxicity of MTUF before and after Ag(I) or Au(II) loading was estimated. The antimicrobial activity tests of MTUF-Ag and MTUF-Au were carried out against Escherichia coli, Salmonella typhimurium and Pseudomonas aeruginosa as examples of Gram negative bacteria; Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, and Bacillus subtilis as examples of Gram positive bacteria; Candida albicans as representative for fungi. The results showed that the minimum inhibitory concentration (MIC) of MTF-Ag against Escherichia coli, Salmonella typhimurium, Listeria monocytogenes, Staphylococcus aureus and Candida albicans were 1.5, 2.0, 1.5, 1.0 and 2.5 mg mL−1, respectively after 40 min of contact time. While MTUF-Au showed higher MIC concentrations: 6.0, 4.0, 4.0, 4.0 and 6 mg mL−1 for the mentioned strains, respectively. The studied MTUF-Ag and MTUF-Au were successfully tested for deactivation of the studied pathogenic microorganism’s water and wastewater samples. It can be concluded that, MTUF-Ag and MTUF-Au are good candidates for water disinfection.

Facile synthesis of magnetic disinfectant immobilized with silver ions for water pathogenic microorganism's deactivation.

One-pot synthesis of a new magnetic disinfectant was achieved through the polymerization of thiourea and formaldehyde in the presence of magnetite nanoparticles (MTUF). The obtained magnetic chelating resin was loaded with Ag(I) ions. This material was tested as a disinfectant for water pathogenic microorganism's deactivation. The toxicity of MTUF before and after Ag(I) loading was estimated. The antimicrobial activity tests of MTUF-Ag were carried out against Escherichia coli, Salmonella Typhimurium, and Pseudomonas aeruginosa as examples of Gram-negative bacteria; Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, and Bacillus subtilis as examples of Gram-positive bacteria; and Candida albicans as representative for fungi. The results showed that the minimum inhibitory dosage (MID) of MTF-Ag against Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, Staphylococcus aureus, and mixed culture were 1.5, 2.0, 1.0, 1.5, and 1.5mg/mL, respectively, after 40min of contact time. While C. albicans was more resistant to the magnetic disinfectant, only three log reductions were done at 2.5mg/mL. The studied MTUF-Ag was successfully tested for water and wastewater pathogenic microorganism's deactivation. It can be concluded that MTUF-Ag could be a good candidate for water disinfection.

Long chain imidazolium ionic liquid and magnetite nanoparticle interactions at the oil/water interface

The influence of the long chain ionic liquid 1-hexadecyl-3-methyl imidazolium chloride on equilibrium and dynamic interfacial tensions of n-heptane/water, as a representative system of oil/water, was investigated. Interfacial tension was drastically decreased by the ionic liquid and presence of magnetite nanoparticles as low as 0.01 wt%. Alkaline pH intensifies this effect. It was while nanoparticles alone had no sensible effect. The equilibrium interfacial tension data were nicely reproduced by the Szyszkowski model. Accordingly, the saturated surface excess for the systems with nanoparticles was decreased compared to the particles free case, but the adsorption equilibrium constant was increased. The dynamic interfacial tension data, on the other hand, showed a good agreement with the mixed diffusion-kinetic control theory for the both cases. Further, the stability of different emulsions was investigated. The results showed that the used nanoparticles were poor emulsifying agent, but the emulsion stability was increased when accompanied with the ionic liquid. Finally, the contact angle of aqueous phase drops surrounded by n-heptane on quartz surface was consistently decreased with the ionic liquid concentration and was more in the presence of nanoparticles.

Compensating effect of ultrasonic waves on retarding action of nanoparticles in drops liquid–liquid extraction

The influence of ultrasonic waves on liquid–liquid extraction of circulating drops and in the presence of magnetite nanoparticles was investigated. Experiments were conducted in a column equipped with an ultrasound transducer. The frequency and intensity of received waves, measured by the hydrophone standard method, were 35.40 kHz and 0.37 mW/cm2, respectively. The recommended chemical system of cumene–isobutyric acid–water was used in which mass transfer resistance lies in the aqueous phase. Nanoparticles, within concentration range of (0.0003–0.0030) wt%, were added to the aqueous continuous phase. The presence of nanoparticles and ultrasonic waves provided no sensible change in drop size (within 2.49–4.17 mm) and measured terminal velocities were close to Grace model. However, presence of nanoparticles, caused mass transfer to decrease. This undesired effect was significantly diminished by using ultrasonic waves so that mass transfer coefficient increased from (73.0–178.2) to (130.2–240.2) µm/s, providing a 55.6% average enhancement. It is presumably due to disturbing the accumulated nanoparticles around the drops. The current innovative study highlights the fact that using ultrasonic waves is an interesting way to improve liquid–liquid extraction in the presence and absence of nanoparticles.

Accelerated ciprofloxacin biodegradation in the presence of magnetite nanoparticles

Ciprofloxacin (CIP) biodegradation was investigated using enrichments obtained in the presence of magnetite nanoparticles, CIP and human fecal sewage. CIP addition inhibited methanogenic activity and altered the bacterial community composition. The magnetite-supplemented enrichments significantly promoted CIP biodegradation, especially in the presence of 2-bromoethanesulfonate (BES). When BES was added, CIP biodegradation in the magnetite-supplemented enrichments was 67% higher than in the magnetite-unamended enrichments. Fe (II) concentrations were also significantly increased in the BES and magnetite-supplemented enrichments. This indicated that there might be a positive relationship of CIP biodegradation with microbial reduction of Fe (III) to Fe (II). As for the magnetite-supplemented enrichments, DNA-sequencing analysis revealed that Stenotrophomonas was the dominant genus, while Desulfovibrio became the dominant genus in the presence of BES. These two genera might be related to Fe (III) reduction in the magnetite. The findings provide a strategy for improving CIP biodegradation during waste treatment.

Toxicity and Applications of Internalised Magnetite Nanoparticles Within Live Paramecium caudatum Cells

The nanotechnology revolution has allowed us to speculate on the possibility of hybridising nanoscale materials with live substrates, yet significant doubt still remains pertaining to the effects of nanomaterials on biological matter. In this investigation, we cultivate the ciliated protistic pond-dwelling microorganism Paramecium caudatum in the presence of excessive quantities of magnetite nanoparticles in order to deduce potential beneficial applications for this technique, as well as observe any deleterious effects on the organisms’ health. Our findings indicate that this variety of nanoparticle is well-tolerated by P. caudatum cells, who were observed to consume them in quantities exceeding 5–12% of their body volume: cultivation in the presence of magnetite nanoparticles does not alter P. caudatum cell volume, swimming speed, growth rate or peak colony density and cultures may persist in nanoparticle-contaminated media for many weeks. We demonstrate that P. caudatum cells ingest starch-coated magnetite nanoparticles which facilitates their being magnetically immobilised whilst maintaining apparently normal ciliary dynamics, thus demonstrating that nanoparticle biohybridisation is a viable alternative to conventional forms of ciliate quieting. Ingested magnetite nanoparticle deposits appear to aggregate, suggesting that (a) the process of being internalised concentrates and may therefore detoxify (i.e. render less reactive) nanomaterial suspensions in aquatic environments, and (b) P. caudatum is a candidate organism for programmable nanomaterial manipulation and delivery.

Magnetic Field Guided Chemotaxis of iMushbots for Targeted Anticancer Therapeutics.

We report controlled migrations of an intelligent and biocompatible "iMushbot" composed of Agaricus bisporus, mushroom microcapsules coated with magnetite nanoparticles. The otherwise randomly moving microbot could meticulously direct itself toward and away from the acid- and alkali-rich regions with the help of acid, acidic catalase, and alkali stimuli, emulating the chemotaxis of microorganisms. Although the catalytic decomposition of peroxide-fuel in alkali engendered the directed alkali taxis toward higher pH region, decomposition of peroxide fuel by the acidic catalase activity led to directed acid taxis toward the lower pH region. The presence of magnetite nanoparticles not only helped in improving the "activity" of the motor through the heterogeneous catalytic decomposition of the peroxide fuel but also provided a remote magnetic control on the chemotaxis. The mesoporous iMushbots having negative ζ-potential could easily be loaded with the cationic anticancer drugs, which were magnetically guided toward the cancerous cells to cause apoptosis. The iMushbots exhibited higher degree of drug retaining capacity inside alkaline pH and showed facile drug release preferentially in the lower pH environments. The experiments show the potential of the iMushbots in retaining and transporting drugs in alkaline medium such as human blood and releasing them in acidic medium such as the cancerous tissues for cell apoptosis.

Synthesis of magnetite from iron-rich mine water using sodium carbonate

In recent decades, much research has been paying attention on the treatment and desalination of acid mine drainage (AMD) with minimal focus on the recovery of minerals from the resultant residues. Solid sludge produced after the treatment process is highly mineralised and technologies are required for the processing of the final sludge for possible industrial application. Conventionally, magnetite is synthesized using iron-rich, industrial grade chemical reagents making magnetite expensive to produce. This has urged the need to come-up with pragmatic and sustainable technologies of recovering magnetite from waste materials. This has led to the development of the present study which aimed at pre-treating AMD in such a way that magnetite could be generated from the recovered sludge. Synthesis of magnetite nanoparticles was evaluated at varying temperature gradients. The principal mechanism governing the metals recovery was selective precipitation. This was achieved by manipulating the pH and aeration rate of the reaction mixture. Experimental results revealed that optimum conditions that are suitable for the recovery of magnetite nanoparticles from AMD were 2:1mol ratio of Fe(II)/Fe(III), pH≥10 and temperature ranging from 25 to 100°C. The purity of synthesized magnetite was 24 (Wt.%) for Al-removed magnetite and 28 (Wt.%) for magnetite synthesized with no Al-removal. Particle size analysis indicated the presence of magnetite nanoparticles having diameters of 0.5nm. SEM-EDS and mapping revealed the presence of Fe and O on the matrices of synthesized material hence confirming that the recovered material is magnetite. This study successfully proved that magnetite nanoparticles can be synthesized from iron-rich mine drainage.

Modification of Mg3Si2O5(OH)4 nanotubes by magnetite nanoparticles

The magnetite nanoparticles and nanocomposite “Nanotube of hydrosilicate Mg—magnetite nanoparticles—Mg-ChR-NT/Fe3O4-NP” were obtained by coprecipitation. The composition of the synthesized samples has been established by X-ray diffraction. Using transmission electron microscopy, the presence of magnetite nanoparticles has been detected both inside the NTs and at the external surface of the NT walls. The specific surface of the NTs, nanoparticles, and composite is determined.

Fabrication and characterization of poly (aniline-co-o-anthranilic acid)/magnetite nanocomposites and their application in wastewater treatment

Nanostructured materials have recently received a growing amount of attention due to their unique properties and wide range of vital applications. In this study, Fe3O4 nanoparticles were coated with different loadings of poly (aniline co-anthranilic acid “PANAA”) copolymer by using surface initiated polymerization (SIP) method. The prepared nanocomposites were characterized by various techniques including FT-IR, TGA, SEM/EDX and XRD. FT-IR data showed that carboxylic groups of PANAA physically interact with magnetite nanoparticles. Thermal stability of PANAA was remarkably improved in the presence of magnetite nanoparticles in the range of 300–800°C. The XRD and SEM analyses indicated that these particles were in the 19–30nm range. The coercivity (Hc) values revealed that the samples are soft magnetic. More in-depth nanostructure were revealed by transmission electron microscopy (TEM). The application of PANAA/magnetite nanocomposites in removing dyes from aqueous solutions were studied.