Fe3O4 MNPs Research Articles

Correction to: 15-Membered Macrocyclic Schiff-Base-Pd(0) Complex Immobilized on Fe3O4 MNPs: An Novel Nanomagnetic Catalyst for the One-Pot Three-Component C–H Chalcogenation of Azoles by S8 and Aryl Iodides

Correction to: 15-Membered Macrocyclic Schiff-Base-Pd(0) Complex Immobilized on Fe3O4 MNPs: An Novel Nanomagnetic Catalyst for the One-Pot Three-Component C–H Chalcogenation of Azoles by S8 and Aryl Iodides

A multifunctional adsorbent based on 2,3-dimercaptosuccinic acid/dopamine-modified magnetic iron oxide nanoparticles for the removal of heavy-metal ions

Overexploitation of nature by humans has led to an increasingly serious issue of heavy-metal water pollution. To reduce the threat of water pollution to humans and the environment, it is imperative to develop or improve the water treatment technology for heavy-metal-containing wastewater. Functionalized Fe3O4 magnetic nanoparticles (Fe3O4 MNPs) have been widely used as effective adsorbents for the removal of heavy-metal ions from water owing to their high efficiency, low cost, selective adsorption ability, and recyclability. In this study, Fe3O4@DA-DMSA magnetic nanoparticles (FDDMs) were prepared by the functionalization of Fe3O4 MNPs with environmentally friendly dopamine (DA) and a heavy-metal detoxifying agent such as 2,3-dimercaptosuccinic acid (DMSA) for the efficient and rapid adsorption of Pb2+, Cu2+, and Cd2+, with maximum adsorption capacities of 187.62, 63.01, and 49.46 mg/g, respectively. FDDMs exhibited the best ability to remove Pb2+ with a maximum adsorption capacity than that of the most reported Fe3O4 MNP-related adsorbents. In actual wastewater and multi-component simulated water samples contaminated with Pb2+, Cu2+, and Cd2+, the as-prepared adsorbent maintained a good removal ability for Pb2+ with low influence by ionic strength and interfering ions, as well as exhibited an excellent selectivity. According to the results of batch experiments and X-ray photoelectron spectroscopy (XPS) analysis of the adsorbent before and after adsorption, the adsorption mechanism of the adsorbent for the removal of heavy-metal ions mainly involves coordination and ion exchange. In addition, the adsorbent exhibited a good regeneration performance. Therefore, FDDMs can be considered as a promising adsorbent for the treatment of heavy-metal wastewater.

Fast synthesis of [1,2,3]-triazole derivatives on a Fe/Cu-embedded nano-catalytic substrate.

Triazoles are biologically important compounds that play a crucial role in biomedical applications. In this study, we present an innovative and eco-friendly nanocatalyst system for synthesizing compounds via the click reaction. The system is composed of Arabic gum (AG), iron oxide magnetic nanoparticles (Fe3O4 MNPs), (3-chloropropyl) trimethoxysilane (CPTMS), 2-aminopyridine (AP), and Cu(i) ions. Using AP as an anchor for Cu(i) ions and Fe3O4 MNPs allows facile separation using an external magnet. The hydrophilic nature of the Fe3O4@AG/AP-Cu(i) nanocomposite makes it highly efficient in water as a green solvent. The highest reaction efficiency (95.0%) was achieved in H2O solvent with 50.0 mg of nanocatalyst for 60 min at room temperature. The reaction yield remained consistent for six runs, demonstrating the stability and effectiveness of the catalyst.

Fe3O4 supported [Cu(ii)(met)(pro-H)2] complex as a novel nanomagnetic catalytic system for room temperature C-O coupling reactions.

In this study, a newly-designed copper(ii) complex of metformin and l-proline which was immobilized on Fe3O4 MNPs was developed. The structure of the catalyst platform was fully characterized using spectroscopic analyses. Moreover, the catalytic activity of [Fe3O4@Cu(ii)(Met)(Pro-H)2] was investigated in a one-pot synthesis of a variety of functionalized ethers in reasonable to excellent yields through Ullman reaction in an aqueous environment using various aryl halides, phenol, and Cs2CO3 and without using any external Cu-reducing agents. Notably, gentle catalytic conditions, quick reaction times, applicability, low cost, and preventing dangerous chemicals and solvents during synthesis and catalytic application are some of the superior properties of the [Fe3O4@Cu(ii)(Met)(Pro-H)2] complex. Furthermore, the catalyst can be reused for several runs (at least eight times) without remarkable loss in efficiency.

Facile synthesis of pyrazolopyridine pharmaceuticals under mild conditions using an algin-functionalized silica-based magnetic nanocatalyst (Alg@SBA-15/Fe3O4).

Pyrazolopyridines are common scaffolds in various bioactive compounds, which have several therapeutic effects and unique pharmacological properties. In this study, we fabricated a novel environmentally friendly silica-based nanocomposite as a multifunctional catalytic system for the synthesis of pyrazolopyridine derivatives. This novel heterogeneous nanocomposite named Alg@SBA-15/Fe3O4 (Alg stands for alginic acid), was prepared in several steps. In this regard, SBA-15 was synthesized by the hydrothermal method. Next, it was magnetized by Fe3O4 nanoparticles via an in situ co-precipitation process. Then, SBA-15/Fe3O4 particles were functionalized with 3-minopropyltriethoxysilane (APTES). Afterward, Alg@SBA-15/Fe3O4 was obtained by a nucleophilic substitution reaction between SBA-15/Fe3O4-NH2 and an as-synthesized methyl-esterified alginic. Different analyses such as Fourier-transform infrared (FTIR), energy-dispersive X-ray (EDX) spectroscopy, field-emission scanning-electron microscopy (FESEM), vibrating-sample magnetometer (VSM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and BET (Brunauer-Emmett-Teller) have been used to confirm the structure of the fabricated catalyst. The magnetic properties of the Alg@SBA-15/Fe3O4 catalytic system imparted by Fe3O4 MNPs enable it to be conveniently isolated from the reaction mixture by using an external magnet. According to the obtained results, the prepared nanocatalyst has high thermal stability and it lost approximately 26% of its weight up to 800 °C. Interestingly, a small amount of prepared nanocatalyst (0.02 g) has shown excellent catalytic performance in the synthesis of pyrazolopyridine derivatives (90-97%) in a short reaction time (20-30 min) at room temperature which can be attributed to its porous structure and large surface area, and the presence of many acidic and basic functional groups. In general, it can be argued that the Alg@SBA-15/Fe3O4 nanocomposite deserves more attention due to its non-toxicity, ease of preparation, good recyclability, and its high catalytic efficiency.

ZIF-67-modified magnetic nanoparticles for extraction of phenoxy carboxylic acid herbicides.

Phenoxy carboxylic acid (PCA) herbicides are commonly used herbicides that can easily accumulate in soil, groundwater, crops, and vegetable surfaces. Thus, they pose a serious risk to human health. Accurate detection of trace amounts of PCAs in various matrixes is crucial. Herein, ZIF-67-modified magnetic nanoparticles (MNPs, ZIF-67@Fe3O4) were prepared by growing ZIF-67 on the surface of Fe3O4 MNPs. The introduction of ZIF-67 improved the dispersion of Fe3O4 nanoparticles in water and enhanced their extraction performance for PCAs. When an eluent consisting of ammonia water and acetonitrile (5% : 95%; v/v) was employed, 10 mg of ZIF-67@Fe3O4 displayed optimal extraction performance for PCAs in a 20 mL sample solution at a pH of 3. We achieved a limit of detection ranging from 0.014 μg L-1 to 0.056 μg L-1 for four types of PCA herbicides by using the newly developed method. Notably, the values were considerably lower than the maximum concentration levels of PCAs in drinking water set by the Environmental Protection Agency. The relative recovery rate of PCAs using ZIF-67@Fe3O4 ranged from 83.75% to 117.07% when applied to river water and apple samples. These results demonstrate the great potential of ZIF-67@Fe3O4 in determining the residues of organic pesticides in real samples.

Thiacalix[4]arene-functionalized magnetic xanthan gum (TC4As-XG@Fe3O4) as a hydrogel adsorbent for removal of dye and pesticide from water medium

A novel thiacalixarene-functionalized biopolymer nanocomposite hydrogel was designed and prepared as an efficient adsorbent system to elimination of aquatic areas from chlorpyrifos (CPF) and crystal violet (CV). This adsorbent system was conducted by multi-step including; preparation of Fe3O4@XG hydrogel through in-situ magnetization of XG, amine modification of Fe3O4@XG hydrogel by using 3-aminopropyltriethoxysilane (APTES) to get Fe3O4@XG-NH2, the synthesis of TC4As supramolecule, its functionalization with epichlorohydrin (ECH) and eventually covalently attachment of ECH-modified TC4As onto as-prepared Fe3O4@XG-NH2 to obtain the TC4As-XG@Fe3O4 nanocomposite hydrogel. Several characterization techniques including FTIR, XRD, FESEM, VSM, TGA, and BET demonstrated the successful synthesis of TC4As-functionalized XG nanocomposite hydrogel. The result of characterization demonstrated that the TC4As-XG@Fe3O4 adsorbent system showed superparamagnetic property with magnetic saturation (Ms) of 9.10 emu/g and high thermal stability with 73 % char yields. The XRD pattern of TC4As-XG@Fe3O4 nanocomposite showed characteristic peaks of Fe3O4 MNPs and XG, but with enhanced crystallinity in compared to neat XG as result of in-situ magnetization of XG as well as its functionalization with TC4As. The BET surface area of Fe3O4@XG and TC4As-XG@Fe3O4 hydrogels was measured approximately 45.32 and 17.30 m2/g, which was higher than neat XG. Then, the constructed adsorbent system was assessed for removing a CPF as an organophosphorus pesticide and CV as cationic dye from aqueous. The batch adsorption experiments were conducted to optimize the effective adsorption parameter i.e., solution pH, adsorbent dosage, contact time, CPF and CV initial concentration. Furthermore, Freundlich isotherm mode was well-fitted model and by utilizing prepared adsorbent, and the maximum adsorption capacities of CPF and CV (at optimum conditions: 298 K, pH 7.0 and 9.0) were found to be about 769.230 and 833.33 mg/g, respectively. The adsorption kinetic study revealed that experimental data were well-fitted by the pseudo-second-order model. Based on proposed mechanism, the CPF and CV were adsorbed onto hydrogel nanocomposite mainly through π–π interactions, electrostatic interaction and hydrogen bonding. The regeneration experiments up to three cycles were best achieved for two studied pollutants.

Fe3O4@SiO2 nanocomposite immobilized with cellulase enzyme: Stability determination and biological activity

The preparation of biocatalysts based on immobilized cellulase is of great importance for proteomic research, industrial applications, and organic synthesis. Herein, Fe3O4 magnetic nanoparticles were synthesized by the coprecipitation method to immobilize the cellulase enzyme and modified to increase its efficiency and stability. Hence, Fe3O4 MNPs were coated with silica by the Stober method, and the surface of Fe3O4@SiO2 nanocomposite was modified with an organosilane. To prevent surface adhesion, the nanocomposite was modified by APTES, and TCT was used as a linker for the immobilization of cellulase. The cellulase enzyme was covalently bonded to the nanocomposite via physical adsorption to synthesize cellulose-Fe3O4@SiO2-NH2 NC and increase its activity and stability. The maximum immobilization of the enzyme occurred at pH = 5, which was close to the isoelectric pH, and the optimum time and temperature for enzyme activity were 1 h and 50 °C. The binding efficiency was around 99 % by using the Bradford method. The maximum activity of the enzyme calculated by the CMC method was 0.08 μmol/min.ml. The adsorption capacity of immobilized cellulase was 33 mg/g toward bovine serum albumin (BSA). The results indicated that the activity and stability of the immobilized enzyme were enhanced in comparison with the free enzyme.

Efficient Synthesis and Antioxidant Activity Evaluation of Novel Fused Indenofurane Derivatives Using Fe3O4-Magnetic Nanoparticles

An efficient one-pot procedure was investigated for the synthesis of new indenofuran derivatives employing poly-phenols and ninhydrins in the presence of magnetically reusable Fe3O4 magnetic nanoparticles (Fe3O4 MNPs) in acetonitrile at different temperatures. Application of nanocatalysts for these reactions caused high efficiency, easy separation of products and clean reactions in a shorter time. Also, a study of antioxidant properties of synthesized compounds was performed using DPPH radical scavenging method and the impact of structural changes on these properties was investigated. The best antioxidant effect was seen for 3a with IC50 0.039 mM relative to BHT as the positive control (0.051 mM). In this paper, it was described that Fe3O4 MNPs can be used instead of glacial acetic acid to synthesize new indenofurane derivatives. The Fe3O4 magnetic nanoparticles improved the yield of the products and demonstrated significant reusable activity. This cost‐effective catalyst has the advantages of high product yields and simple work‐up procedures as well as high thermal and mechanical stability. HIGHLIGHTS Indeno[1,2-b]furans are attractive scaffolds because of their efficiency of synthesis and bioactivity properties. Indeno[1,2-b]furans, in particular, received considerable attention from a synthetic and biological perspective. During the synthesis of Indenofuran compounds, the Fe3O4 nanocatalyst shows better catalytic activity than their bulk-sized samples and also other catalysts. Efficient nanocatalyst with easy recovery and reusability.

Nanozyme-Based Lateral Flow Immunoassay (LFIA) for Extracellular Vesicle Detection.

Extracellular vesicles (EVs) are biological nanoparticles of great interest as novel sources of biomarkers and as drug delivery systems for personalized therapies. The research in the field and clinical applications require rapid quantification. In this study, we have developed a novel lateral flow immunoassay (LFIA) system based on Fe3O4 nanozymes for extracellular vesicle (EV) detection. Iron oxide superparamagnetic nanoparticles (Fe3O4 MNPs) have been reported as peroxidase-like mimetic systems and competent colorimetric labels. The peroxidase-like capabilities of MNPs coated with fatty acids of different chain lengths (oleic acid, myristic acid, and lauric acid) were evaluated in solution with H2O2 and 3,3,5,5-tetramethylbenzidine (TMB) as well as on strips by biotin–neutravidin affinity assay. As a result, MNPs coated with oleic acid were applied as colorimetric labels and applied to detect plasma-derived EVs in LFIAs via their nanozyme effects. The visual signals of test lines were significantly enhanced, and the limit of detection (LOD) was reduced from 5.73 × 107 EVs/μL to 2.49 × 107 EVs/μL. Our work demonstrated the potential of these MNPs as reporter labels and as nanozyme probes for the development of a simple tool to detect EVs, which have proven to be useful biomarkers in a wide variety of diseases.

Lysosome-targetable brightly green fluorescence carbon dots for real-time monitoring in cell and highly efficient removal in environment of hypochlorite

Due to the lacks of lysosome localization group and reaction/interaction site for hypochlorite (ClO-) on the surface of the carbon dots (C-dots), no C-dots-based lysosome-targeted fluorescence probes have, so far, been reported for real-time monitoring intracellular ClO-. In this work, 1,3,6-trinitropyrene (TNP) was used as a precursor to prepare C-dots with maximum excitation and emission wavelengths at 485 and 532 nm, respectively, and quantum yield ∼ 27% by a hydrothermal approach at 196 °C for 6 h under a reductive atmosphere. The brightly green C-dots can sensitively and quickly respond to ClO- in aqueous solution through surface chemical reaction, showing a linear relationship in the range of 0.5–120 μΜ ClO- with 0.27 μΜ of limit of detection (LOD). Most significantly, the C-dots can localize at intracellular lysosome to image ClO- in lysosomes. Also, the magnetic nanocomposites (C-dots@Fe3O4 MNCs) were fabricated via a simple electrostatic self-assembly between Fe3O4 magnetic nanoparticles (Fe3O4 MNPs) and C-dots for highly efficient removal of ClO- in real samples. Therefore, lysosome-targetable C-dots-based probes for real-time monitoring ClO- were successfully constructed, opening up a promising door to investigate the biological functions and pathological roles of ClO- at organelle levels.

Superparamagnetic Iron Oxide Nanoparticles Induce Apoptosis in HT-29 Cells by Stimulating Oxidative Stress and Damaging DNA.

Nanoparticles have garnered considerable scientific attention in recent years due to their diagnostic and therapeutic applications in cancer. The purpose of this study was to determine the effect of superparamagnetic iron oxide nanoparticles (Fe3O4 MNPs) on the induction of apoptosis in human colorectal adenocarcinoma cell line (HT-29) cells. The purpose of this study was to elucidate the mechanisms of apoptosis induced by Fe3O4 MNPs following MTT assay and to determine the optimal dose of 2.5g/mL for inducing apoptosis in HT-29 cells. In HT-29 cells, Fe3O4 MNPs increased reactive oxygen species (ROS), calcium ion (Ca2+), and DNA damage. Additionally, the Fe3O4 MNPs significantly increased caspase 3 and 9 expression and decreased Bcl-2 expression at the protein and mRNA levels when compared to the control group (P = 0.0001). Fe3O4 MNPs also induced apoptosis in cancer cells by increasing the level of (ROS) and intracellular Ca2+, followed by an increase in caspase 3 and 9 expression and a decrease in Bcl-2 expression and direct DNA damage. Fe3O4 MNPs are an appropriate choice for colon cancer treatment based on their cell toxicity and induction of apoptosis in HT29 cells.

The triazole-thiol-functionalized Mn-complex and its catalytic performance

The novel magnetic triazole-thiol-functionalized Mn-complex was obtained by preparation of the Fe3O4 magnetic nanoparticles, coating of Fe3O4 MNPs with tetraethyl orthosilicate, functionalization with both 3-chloropropyltrimethoxysilane (CPTMS) and 1-H-1,2,4-triazole-3-thiol (TT) ligands, and further complexation with manganese acetate. Then, the supported Mn catalyst (Fe3O4@SiO2@CPTMS@TT@Mn) was characterized by various methods (FT-IR, XRD, EDX, ICP, SEM, SEM-mapping, SEM-Histograms, TEM, TGA-DTA, VSM, and BET) and used as a heterogeneous nano-catalyst for the synthesis of diverse N-benzylated cyanamides from the reaction of various aryl cyanamides with benzyl bromide and K2CO3 in acetonitrile at 60 °C in appropriate times.

RETRACTED: Nanomagnetic Salamo-based-Pd(0) Complex: an efficient heterogeneous catalyst for Suzuki–Miyaura and Heck cross-coupling reactions in aqueous medium

In order to develop a magnetic nanocatalyst, an asymmetric salamo-based-Palladium(0) complex grafted on Fe3O4 MNPs was synthesized and characterized using physicochemical methods including FT-IR, XRD, SEM, TEM, EDS, ICP-AES, X-ray mapping, TGA and VSM analyses. Catalytic activities of [Fe3O4@H2L‐Pd (0)] were examined towards two catalytic reactions: a) synthesis of biaryls via the Suzuki C-C cross-coupling of phenylboronic acid with aryl halides and b) one-pot synthesis of butyl cinnamates via the Heck C-C cross-coupling of butyl acrylate with aryl halides under green conditions in aqueous medium. Moreover, the effects of the catalyst amount, reaction temperature, type of the solvent and nature of base on catalytic activity were investigated. The [Fe3O4@H2L‐Pd(0)] nanocatalyst was recycled for at least six consecutive reaction cycles without a significant loss of its catalytic activity. This illustrates the sustainable anchoring of palladium(0) on Fe3O4.

Nanomagnetic macrocyclic Schiff-base-Mn(ii) complex: an efficient heterogeneous catalyst for click approach synthesis of novel β-substitued-1,2,3-triazoles.

In the present work, a novel symmetrical 15-membered macrocyclic Schiff base complex of manganese was prepared using the reaction of the synthetic 2,6-diacetylpyridine functionalized Fe3O4 MNPs with 2,2-(piperazine-1,4-diyl)dianiline and Mn(ii) bromide salt via a template approach. The resulting [Fe3O4@PAM–Schiff-base–Mn][ClO4] heterogenized complex was characterized using FT-IR, XRD, BET, TGA, EDX, Xray-mapping, SEM, TEM and VSM analysis. To demonstrate proof of concept, Huisgen 1,3-dipolar cycloaddition synthesis of 1,2,3-triazoles was selected to evaluate the activity and reusability of the catalyst. The ethanol as a green solvent proved to be an excellent reaction medium for this synthesis. Yields of up to 100% were obtained in some cases. Significantly, as demonstrated, [Fe3O4@PAM–Schiff-base–Mn][ClO4] catalyst was recycled for 8 cycles without losing catalytic activity under the optimized reaction conditions. The hot filtration and ICP-OES tests ratified that there was no leaching of metal during the catalytic reaction, indicating the heterogeneous manner of the catalyst.

Green synthesis of novel 5-amino-bispyrazole-4-carbonitriles using a recyclable Fe3O4@SiO2@vanillin@thioglycolic acid nano-catalyst.

Bis(thioglycolic acid)-vanillin (2,2'-(((4-hydroxy-3-methoxyphenyl)methylene)bis(sulfanediyl))diacetic acid)-functionalized silica-coated Fe3O4 magnetic nanoparticles (Fe3O4@SiO2@vanillin@thioglycolic acid MNPs) were synthesized and characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis/differential thermogravimetry (TGA-DTG), X-ray powder diffraction (XRD), X-ray spectroscopy (EDX), vibrating sample magnetometry (VSM), zeta potential measurements and Fourier transform infrared spectroscopy (FT-IR). The ensuing MNPs offer an environmentally friendly procedure for the synthesis of novel 5-amino-pyrazole-4-carbonitriles via a three-component mechanochemical reaction of synthesized azo-linked aldehydes or synthesized pyrazolecarbaldehydes, malononitrile, and phenylhydrazine or p-tolylhydrazine adhering to the green chemistry principles; products were generated expeditiously in high yields. The catalyst could be quickly recovered and reused for six cycles with almost consistent activity. The structures of the synthesized 5-amino-pyrazole-4-carbonitrile compounds were confirmed by 1H NMR, 13C NMR, and FTIR spectra and elemental analyses. This new procedure has notable advantages such as operational simplicity, excellent yields, short reaction time, easy work-up, eco-friendliness and nontoxic catalyst. Also the catalyst can be easily recovered by an external magnetic field and reused for six consecutive reaction cycles without significant loss of activity.

Individual iron(iii) glycerolate: synthesis and characterisation

Iron(ii) and iron(iii) salts of strong acids form iron glycerolates on heating at 180 °C with glycerol in the presence of an equivalent amount of alkali. Individual iron(iii) glycerolate was obtained for the first time. When Fe3O4 magnetic nanoparticles were heated with glycerol, an iron(iii) glycerolate shell was formed on their surface.

XPS\xa0and structural studies of Fe3O4-PTMS-NAS@Cu as a novel magnetic natural asphalt base network and recoverable nanocatalyst for the synthesis of biaryl compounds

In this research, natural asphalt as a mineral carbonuous material was converted to sodium natural asphalt sulfonate (Na-NAS) and, then, was linked to Fe3O4 MNPs in order to synthesize the magnetic nanocatalyst. Afterwards, Cupper (I) and Cu (II) was grafted on Fe3O4-PTMS-NAS. Moreover, it is worth mentioning that the synthesized the novel magnetic nanocatalyst (Fe3O4-PTMS-NAS@Cu) was successfully used in Suzuki and Stille coupling reactions. The Fe3O4-PTMS-NAS@Cu MNPs were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), inductively coupled plasma (ICP), BET and X-ray photoelectron spectroscopy (XPS) analysis. Besides, sulfonation of natural asphalt, magnetization of catalyst, grafting of Cu (I) and Cu (II) to NAS and catalyst formation were investigated and proved carefully. This nanocatalyst can be comfortably separated from the reaction medium through an external magnetic field and can also be recovered and reused, while maintaining its catalytic activity.

Selectivity adjustment of Fe3O4 MNPs based silver catalyst in oxidation of sulfides with classical and ultrasonic methods and synthesis of 5-substituted 1H-tetrazoles from aryl nitriles in water

The surface of the Fe3O4 has been functionalized with 3-chloropropyltrimethoxysilane, which undergoes an SN2 substitution reaction of the chloro group with the nitrogen of ligand (creatinine), offering the Fe3O4@Creatinine. A new recyclable Ag attached Fe3O4 MNPs (Fe3O4 @Creatinine@Ag) has been produced through a post-synthetic method. FT-IR (Fourier Transforms Infrared), TGA (Thermogravimetric Analysis), XRD (X-ray Diffraction), EDS (Energy-Dispersive X-ray Spectroscopy) and VSM (Vibrating Sample Magnetometer) confirm the effectiveness of the performed chemical modification to synthesize the catalyst. This catalyst displays high catalytic performance in the synthesis of 5-substituted 1H-tetrazoles in water and the selective oxidation of sulfides. In the presence of nano- Fe3O4 @Creatinine@Ag as an efficient heterogeneous nano-catalyst, the corresponding 5-substituted 1H-tetrazoles and sulfoxide were afforded under the mild condition in good to excellent yields. A wide variety of sulfides furnished the corresponding sulfoxide with classical and ultrasonic methods. The results show that ultrasonic is an appropriate method for the oxidation of sulfides to the related sulfoxide. The catalyst can be separated by simple recovery and reused for several periods without any remarkable decrease in the catalysis activity and selectivity.In the synthesis of this catalyst, the environmentally friendly ligand is used to stabilize the eco-friendly active site on the desired support. What distinguishes this catalyst and this research is its high eco-friendliness in several respects. The structure of this catalyst and also, the reaction are based on green chemistry. At a relatively low temperature compared to the reported work, tetrazole derivatives are prepared in water solvent with good efficiency.

Gelatin grafted Fe3O4 based curcumin nanoformulation for cancer therapy

Combination of natural polymer and nanoparticle has always been fascinating for biomedical applications. Here, we have demonstrated a simplified dessolvation-coprecipitation technique for the development of gelatin grafted Fe3O4 magnetic nanoparticles (Gel-MNPs), and investigated their potential applications in drug delivery and hyperthermia therapy. XRD, TEM, FTIR, TGA and light scattering techniques were used to confirm the phase formation of core Fe3O4 MNPs and their successful surface modification with gelatin moieties. The Gel-MNPs showed good aqueous colloidal stability and pH dependent surface charge characteristics. The hydrophobic anticancer agent, curcumin was employed as a model drug to investigate the loading and release properties of Gel-MNPs. A loading efficiency of about 95% was achieved at drug to particle ratio of 1:10 and curcumin loaded Gel-MNPs (Cur-Gel-MNPs) exhibited pH dependent release behaviour of loaded drug with higher release at mild acidic environment. These Cur-Gel-MNPs have shown dose dependent cytotoxicity towards lung (A549) and breast (MCF-7) cancer cell lines. Further, CUR-Gel-MNPs exhibited enhanced heat activated killing of cancer cells under AC magnetic field, suggesting their usefulness for magnetic hyperthermia therapy.