Magnetic Graphene Nanocomposite Research Articles

From Corn Starch to Nanostructured Magnetic Laser-Induced Graphene Nanocomposite.

Laser-Induced Graphene (LIG) is a 3D, conductive, porous material with a high surface area, produced by laser irradiation of synthetic polymers with high thermal stability. Recently, the focus has shifted toward sustainable bioderived and biodegradable precursors, such as lignocellulosic materials. Despite starch being an abundant and cost-effective biopolymer, direct laser scribing on starch-derived precursors has not yet been explored. This study demonstrates that corn starch bioplastic (SP) can be converted into LIG through iron-catalyzed laser-induced pyrolysis, using Fe(NO₃)₃ as an additive. The impact of iron additive concentration on LIG formation and on its properties is investigated, with only certain concentrations yielding reliable and reproducible results. The investigation of LIG's crystal structure reveals magnetic and non-magnetic iron phases: γ-Fe₂O₃, Fe₃C, and Fe(C). The LIG nanocomposite exhibits soft magnetic properties, with a coercive field of Hc ≈ 200Oe and a saturation magnetization of Ms ≈ 67 emu g⁻¹. The SP substrate degrades almost entirely in soil within 12 days and is unaffected by the addition of Fe(NO₃)₃, allowing for material compostability in line with circular economy principles. Consequently, SP stands out as a promising "green" precursor for magnetic LIG, paving the way for sustainable applications in environmental remediation.

A novel in-situ synthesis of magnetic graphene nanocomposites by Fe2(SO4)3 intercalation for removal of congo red from water: adsorption investigation and mechanism insights

A novel in-situ synthesis of magnetic graphene nanocomposites by Fe2(SO4)3 intercalation for removal of congo red from water: adsorption investigation and mechanism insights

Hard Magnetic Graphene Nanocomposite for Multimodal, Reconfigurable Soft Electronics.

Soft electronics provide effective means for continuous monitoring of a diverse set of biophysical and biochemical signals from the human body. However, the sensitivities, functions, spatial distributions, and many other features of such sensors remain fixed after deployment and cannot be adjusted on demand. Here, laser-induced porous graphene is exploited as the sensing material, and dope it with permanent magnetic particles to create hard magnetic graphene nanocomposite (HMGN) that can self-assemble onto a flexible carrying substrate through magnetic force, in a reversible and reconfigurable manner. A set of soft electronics in HMGN exhibits enhanced performances in the measurements of electrophysiological signals, temperature, and concentrations of metabolites. All these flexible HMGN sensors can adhere to a carrying substrate at any position and in any spatial arrangement, to allow for wearable sensing with customizable sensitivity, modality, and spatial coverage. The HMGN represents a promising material for constructing soft electronics that can be reconfigured for various applications.

Preparation of magnetic graphene nanocomposite based on metallic iron and its application in the extraction and preconcentration of some pesticides from fruit juice, river water, and wastewater samples

Preparation of magnetic graphene nanocomposite based on metallic iron and its application in the extraction and preconcentration of some pesticides from fruit juice, river water, and wastewater samples

Magnetically purification/immobilization of poly histidine-tagged proteins by PEGylated magnetic graphene oxide nanocomposites

Carbon-based nanomaterials have many applications in biomedicine due to their unique mechanical, chemical, and biological properties. Among them, graphene has received special attention due to its very high specific surface area, high flexibility, and chemical stability. In this study, graphene oxide was first functionalized with amine groups (GO-NH2) and then Fe3O4 nanoparticles were deposited on it using the hydrothermal method. In addition, polyethylene glycol (PEG) was attached to the magnetic graphene nanoparticles to increase their stability and solubility. Finally, PEGylated magnetic graphene nanocomposites were functionalized with nickel-nitrilotriacetic acid (NTA-Ni+2) to bind to the poly-histidine tag in recombinant proteins. The resulting nanocomposites (MG-PEG-NTA-Ni+2) were then used for magnetic immobilization and purification of recombinant β-NGF as a protein with his-tag sequence. Binding and purification were confirmed by FTIR and SDS-PAGE techniques, respectively. Importantly, differentiation of the PC12 cell line into neurons demonstrated that the purified β-NGF was fully functional. Our results suggest that MG-PEG-NTA-Ni+2 nanocomposites may be a suitable alternative to commercial resins for rapid and specific protein immobilization and purification.

Magnetic few-layer graphene nanocomposites for the highly efficient removal of benzo(a)pyrene from water

Magnetic graphene-based composite nanomaterials were developed to capture benzo(a)pyrene from water media. The synthesized nanomaterials couple very easy magnetic separation after adsorption with highly efficient removal of ∼99.9%.

BIOSSENSOR PARA NÍVEL DE INSULINA SANGUÍNEO EM ATLETAS

ABSTRACT Introduction: The pancreas releases insulin to assist the human body in utilizing blood glucose. It regulates metabolism by promoting the absorption of glucose into the blood. Objective: This work aimed to create an electrochemical biosensor based on magnetic graphene nanomaterial to measure insulin levels in athletes’ blood. Method: A magnetic graphene nanocomposite created by graphene oxide (GO) and Fe-Ni bimetallic oxides on a glassy carbon electrode was synthesized using the electrochemical deposition method (GCE). Results: The immediate electrical deposition of Fe-Ni bimetallic oxide nanoparticles with the spherical shape on the GO nanosheet without aggregations was validated by structural characterizations of Fe-Ni/GO/GCE using XRD and SEM. The electrochemical results for insulin determination showed good sensitivity and anti-interference capability. The applicability and accuracy of the proposed electrochemical sensor to detect insulin were explored by blood serum samples from sportsmen. Conclusion: The results assigned acceptable RSD values (3.31% to 4.30%) and confirmed the feasibility of the proposed sensor for detecting athletes’ blood insulin. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Phthalocyanine-mediated interfacial self-assembly of magnetic graphene nanocomposites toward low-frequency electromagnetic wave absorption

Exploring multi-component composite is promising for advanced electromagnetic wave (EMW) absorption materials, yet challenged by balancing low-frequency absorption and cost-effective preparation mode. Herein, a series of dielectric-magnetic nanocomposites are fabricated as EMW absorbers via facile phthalocyanine-mediated interfacial self-assembly approach. Phthalocyanine could act as a functional reagent to modify magnetic Fe3O4 nanosphere and guarantee the self-assembly with reduced graphene oxide nanosheet simultaneously. Owing to the flexible self-assembly, the as-synthesized ternary nanocomposite exhibits highly tunable EMW absorption performance toward low-frequency absorption. The minimum reflection loss reaches −49.0 dB (99.998 % wave absorption) simultaneously at a low frequency of 5.4 GHz and a high frequency of 8.3 GHz, which displays superb absorption efficiency in both the C band and X band. The phthalocyanine-mediated dielectric-magnetic synergy endows the nanocomposite with enhanced impedance matching and multiple dissipation pathways. This study demonstrates a convenient strategy for the rational design of low-frequency EMW absorbers with high-efficiency absorption.

Preparation of Electrochemical Sensor Based on Magnetic Graphene Nanocomposite for Determination of Dopamine

Preparation of Electrochemical Sensor Based on Magnetic Graphene Nanocomposite for Determination of Dopamine

Magnetic Graphene nanocomposite: Synthesis, Properties, and Biological Applications

Magnetic Graphene nanocomposite: Synthesis, Properties, and Biological Applications

Monodispersed magnetographene quantum dot nanocomposites for delivery of silibinin

Silibinin shows multi-applications and therapeutic activities such as anticancer, antioxidant, hypocholesterolemic, cardioprotective, neuroprotective and hepatoprotective but exhibits limited clinical applications due to poor oral bioavailability and in-vitro in-vivo biological correlation. The present study focused on the characterization of magnetic graphene quantum dot nanocomposites for silibinin delivery with a specific interest in kidney cancer treatment optimized by a central composite design. The effect of the composition of polylactic-co-glycolic acid (PLGA), polyvinyl alcohol (PVA) and silibinin on the mean particle size and encapsulation efficiency was studied. The properties of the synthesized magnetic graphene nanocomposites by using silibinin magnetic nanoparticles determined by central composite design method revealed particle size below 300 nm, high encapsulation efficiency (81.27 %) and cumulative in-vitro drug release exhibited in sustained manner. In vitro cellular uptake studies with kidney cancer cell line (A-498) demonstrated that the magnetic graphene quantum dot nanocomposites presented higher cellular uptake of silibinin and cytotoxicity than graphene quantum dots. The in-vivo pharmacokinetic study demonstrated a significant improvement in drug bioavailability with better mean residence time due to prolong exposure in systemic circulation. Therefore, monodispersed magnetic graphene quantum dot nanocomposites are considered as an interesting alternative for silibinin delivery against kidney cancer cell line A-498.

A magnetic graphene nanocomposite for efficient removal of methylene blue from wastewater

Nanostructured materials have several advantages over their bulk counterparts that can be exploited for water treatment. A magnetic graphene nanocomposite (Fe3O4/G) abbreviated as (MG) was synthesized using a solvothermal method and fully characterized using high-resolution transmission electron microscope (HR-TEM), X-ray diffraction (XRD), a vibrating sample magnetometer (VSM), Fourier transform infrared (FTIR) spectroscopy and zeta-potential measurements. Adsorption experiments for methylene blue (MB) dye removal were performed under different conditions. Parameters such as the initial dye concentration, pH, adsorbate/adsorbent contact time, adsorbent dosage and temperature were investigated. The dye removal efficiency was measured using a spectrophotometer. The results revealed that the adsorption behavior follows a pseudo-second-order kinetic model, and equilibrium was achieved after 15 min. The equilibrium data were well fitted with the Langmuir and Freundlich isotherm models. The MG nanocomposite exhibits an excellent removal efficiency (100%) for MB dye, and the magnetic properties of the magnetite nanoparticles in the nanosorbent allow a fast, magnetic separation of the adsorbent from an aqueous solution.

Double molecular recognition ligands modified CPDS/CMCS/Fe3O4-rGO hybrid with enhanced enrichment capacity for glycoproteins at neutral environment

Abstract In order to achieve specific enrichment of target glycoproteins, double molecular recognition ligands functionalized surface solid-phase adsorption materials that can play a role under physiological pH conditions, have obvious advantages. In this work, a novel strategy was proposed for the synthesis of double molecular recognition functionalized magnetic graphene nanocomposites. Horseradish peroxidase was selected as the template proteins for evaluating the selectivity and binding capacity of the adsorption material. The bimolecular recognition was realized by introducing 4-carboxyphenylboronic acid (CPBA) and Suberic acid bis(3-sulfo-N-hydroxysuccinimide ester) sodium salt (Sulfo-DSS) as functional ligands. The abundant oxygen-containing groups in the complex (abbreviated as CPDS/CMCS/Fe3O4-rGO) were beneficial to reduce the pKa value of CPBA. Finally, CPDS/CMCS/Fe3O4-rGO realized the selective adsorption of glycoproteins in the neutral environment (pH 7.0). The resultant CPDS/CMCS/Fe3O4-rGO exhibited a high adsorption capacity of 1280.6 mg g−1 and excellent specificity toward glycoproteins compared to nonglycoproteins. Moreover, CPDS/CMCS/Fe3O4-rGO with strong magnetic responses (59.29 emu·g−1), could achieve rapid aggregation and separation under the external magnetic field. The results demonstrated the great potential of CPDS/CMCS/Fe3O4-rGO composites to separate and enrich glycoproteins from the complex biological sample for the glycoproteins analysis.

Preparation of magnetic graphene nanocomposite for the removal of cefixime from aqueous solution

ABSTRACT The magnetite graphene nanocomposite (G/Fe3O4) obtained from banana peels was prepared via a simple and green technique and utilised as an environmental-friendly adsorbent for cefixime(CFX) removal. The G/Fe3O4 nanocomposite was characterised by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometry (VSM), atomic force microscopy (AFM), Brunauer, Emmett, and Teller (BET), and UV–visible spectrophotometer. The adsorption parameters, including the initial CFX concentration, contact time, solution pH, temperature, and adsorbent dosage, were investigated. The adsorption kinetic and isotherm were well fitted by the pseudo second-order and Langmuir models, respectively. The results showed that the maximum adsorption capacities of CFX on G/Fe3O4 nanocomposite was 285.71 mg g−1 andBET surface area of G/Fe3O4 nanocomposite was1905.5 m2 g−1.

Inkjet printed self-healable strain sensor based on graphene and magnetic iron oxide nano-composite on engineered polyurethane substrate

In recent years, self-healing property has getting tremendous attention in the future wearable electronic. This paper proposes a novel cut-able and highly stretchable strain sensor utilizing a self-healing function from magnetic force of magnetic iron oxide and graphene nano-composite on an engineered self-healable polyurethane substrate through commercialized inkjet printer DMP-3000. Inducing the magnetic property, magnetic iron oxide is applied to connect between graphene flacks in the nano-composite. To find the best nano-composite, the optimum graphene and magnetic iron oxide blending ratio is 1:1. The proposed sensor shows a high mechanical fracture recovery, sensitivity towards strain, and excellent self-healing property. The proposed devices maintain their performance over 10,000 times bending/relaxing cycles, and 94% of their function are recovered even after cutting them. The device also demonstrates stretchability up to 54.5% and a stretching factor is decreased down to 32.5% after cutting them. The gauge factor of the device is 271.4 at 35%, which means its sensitivity is good. Hence, these results may open a new opportunity towards the design and fabrication of future self-healing wearable strain sensors and their applied electronic devices.

Dye removal with magnetic graphene nanocomposite through micro reactors

Contaminated waste water treatment and clean water scarcity are current challenges acutely in the Asian and African continents. This paper bestows applied co-precipitation technique for the fabrication of Magnetic Graphene Nano-Composites (MGNCs) for water treatment purposes. In this paper, characterization procedures were applied to delineate numerous physical and chemical properties of the synthetic MGNCs and mixing performance for several designed microreactors were determined using the Dushman’s method in comparison to two parallel reactions. The mixing timings for different microreactors at flow rates between 100 and 300 ml/hr were determined. MCNCs were utilised to remove an Acid Blue 25 dye as a pollutant from water at diverse types of microreactors. The comparison between the various microreactors’ performance and mixing time was accomplished. The maximum instantaneous removal capacity of graphene-based nanomaterial was recorded using K.M micro mixer about 68% for 10 ppm dye concentration.

Comparative study for removal of nitro-heterocyclic explosives using magnetic graphene nanocomposites

In this manuscript, RDX (Royal Demolition eXplosive) and HMX (High Melting eXplosive) were removed from water that is mainly polluted by military activities. Two different forms of magnetic graphene oxide nanocomposites, α-Fe2O3-rGO (hematite-reduced graphene oxide) and nZVI-rGO (nano zero valent iron-reduced graphene oxide) have been evaluated for decontamination of water containing these carcinogenic explosives. Comparative adsorption studies were carried out considering contact time, pH and adsorbent dosage for all the adsorbent–adsorbate systems. Batch adsorption experiments at varied concentrations of RDX and HMX were conducted. The experimental results better fit in pseudo second order model following Freundlich isotherm. Magnetic nature of both adsorbents is suitable for their easy separation from contaminated water in presence of an external magnetic field. α-Fe2O3-rGO showed higher adsorption capacities for HMX and RDX, this was supported by the physio-chemical properties of the adsorbent. Therefore, it could be potentially upscaled and used commercially for purification of water containing explosives.

Hyperthermia response of PEGylated magnetic graphene nanocomposites for heating applications and accelerate antibacterial activity using magnetic fluid hyperthermia

In this research work, graphene/cobalt nanocomposites are functionalized with polyethylene glycol (PEG) to be a platform for theranostics application and antibacterial activity. The non-covalent functionalization of PEG on the surfaces of nanocomposites improved their stability and diminished their cytotoxicity. The PEGylated nanocomposites are demonstrated to allow simultaneous administration of two cancer therapy methods such as magnetic fluids hyperthermia (MFH) which is carried out by converting magnetic energy into heat through ferromagnetic cobalt nanoparticles and heat generation through near-infrared optical absorption by the reduced graphene oxide. A concise simulation is carried out to approximate in vivo conditions and provide a glimpse of practical PEGylated nanocomposites performance. Furthermore, we demonstrate the antimicrobial activity of the PEGylated nanocomposites against Gram-negative Escherichia coli bacteria under alternative current magnetic field (AMF). The graphene/cobalt/PEG (rGO/Co/PEG) nanocomposites show antibacterial activity toward E. coli bacteria of about 100%, when the bacteria intact with nanocomposites are placed under AMF for 15 min. For comparison, the antimicrobial activities of graphene/PEG sheets and cobalt/PEG nanoparticles are also checked. This study concentrates on the design of novel non-toxic PEGylated nanocomposites to be used for dual hyperthermia therapy and bacteria killing by MFH treatments.

Laccase immobilized polyaniline/magnetic graphene composite electrode for detecting hydroquinone

Magnetic graphene nanocomposites were prepared by hydrothermal synthesis, and aniline polymerization was initiated by magnetic graphene. These polyaniline/magnetic graphene (PANI/MG) composites were used to immobilize laccase to construct biosensors. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and infrared spectroscopy (IR) were used to characterize these composites. Cyclic voltammetry and chronoamperometry technique were used to test the electrical properties of the constructed polyaniline/magnetic graphene laccase modified electrode. The results show that the polyaniline/magnetic graphene immobilizing laccase modified electrode exhibited superior electrical properties, including high sensitivity, detection limit and linear range. The hydroquinone was used as an analytical and detection probe. The selectivity was 0.03639 A/(mol/L), the linear range was 0.4–337.2 μmol/L, and the detection limit was 2.94 μM (signal/noise = 3, minimum identification value of effective signal). The biosensor can reach the conditions for detecting the actual water sample.

Facile synthesis of hydrophilic magnetic graphene nanocomposites via dopamine self-polymerization and Michael addition for selective enrichment of N-linked glycopeptides

The development of methods to effectively capture N-glycopeptides from the complex biological samples is crucial to N-glycoproteome profiling. Herein, the hydrophilic chitosan–functionalized magnetic graphene nanocomposites (denoted as Fe3O4-GO@PDA-Chitosan) were designed and synthesized via a simple two-step modification (dopamine self-polymerization and Michael addition). The Fe3O4-GO@PDA-Chitosan nanocomposites exhibited good performances with low detection limit (0.4 fmol·μL−1), good selectivity (mixture of bovine serum albumin and horseradish peroxidase tryptic digests at a molar ration of 10:1), good repeatability (4 times), high binding capacity (75 mg·g−1). Moreover, Fe3O4-GO@PDA-Chitosan nanocomposites were further utilized to selectively enrich glycopeptides from human renal mesangial cell (HRMC, 200 μg) tryptic digest, and 393 N-linked glycopeptides, representing 195 different glycoproteins and 458 glycosylation sites were identified. This study provides a feasible strategy for the surface functionalized novel materials for isolation and enrichment of N-glycopeptides.