Sharif Digital Repository

Drug targeting to specific organs and tissues has become one of the critical endeavors of the new century. Magnetic nanoparticles have gained a lot of attention in biomedical and industrial application. Doxorubicin is an effective anti-cancer drug in the treatment of many types of cancers. The aim of this study is to load doxorubicin on stimuli-responsive nanocarriers. These nanocarriers are prepared from magnetic nanoparticles. Then these magnetic nanparticles are coated by copolymer of poly(glycidyl methacrylate) then reacted with hydrazine and hydrazide functional group is formed that can chemically be bonded with the anticancer drug doxorubicin via a hydrazone bond formation. This... 

One of the most challengeable topic in the field of green chemistry is the synthesis of organic structure in water. In this project immobilized glucose on Fe3O4 was prepared as a nano heterogeneous dispersive catalyst in water. The catalyst was fully characterized by FT-IR, TGA, CHN, SEM, EDX and atomic absorption spectroscopy. The synthesized catalyst was used in the synthesis of different derivatives of 1,2,3-triazole via one-pot three component reaction of alkynes, alkyl halides, sodium azides; And to the best of our knowledge this novel catalyst coin sides to the principles of green chemistry. This nano catalyst can be recycled and reused for several runs without significant loss of its... 

Iron oxide nanoparticles were synthesized using microemulsion technique as MRI contrast agents. Utilization of nanoparticles for biological applications and in this case as MRI contrast agents needs particles to be of small size and also narrow size distribution. For this aim, the effect of several parameters on size and size distribution has been studied. These parameters include water/surfactant ratio, precursor’s concentration and amount of polymer employed to improve nanoparticles colloidal stability. XRD, FE-SEM and TEM results reveal that the synthesized nanoparticles had small size (about 10 nm iron oxide core and 20 nm overall diameter) and possessed narrow size distribution (15-21... 

Nowadays , application of enzymes as biocatalysts in wastewater treatment processes is increasing. It is economically important to reuse enzymes and increase their stability in these types of processes. Therefore, was immobilization of enzymes and using them in wastewater treatment have a great importance.In this project, Horseradish peroxidase enzyme, whose effect on phenol removal reactions in other studies has been proven before, was immobilized on the alginate-coated magnetic nanoparticles, to investigate the effect of immobilization on the stability and function of this enzyme for phenol removal. The enzyme was immobilized at the temperature of 25 ° C and pH = 8, according to the data... 

Photocatalysts are compounds that can perform oxidation and reductions in the presence of light. One of the most known applications for photocatalyst is degrading organic contaminants in wastewater and making them harmless to the environment.In this project, a magnetic photocatalyst based on Fe3O4@ZnO/N-RGO has been synthesized and characterized with FT-IR, FE-SEM and EDS, XRD, and TGA. Moreover, photocatalytic dye degradation reactions for Rhodamine B, Methylene Blue, and Methyl Orange have been investigated and compared in the presence of Fe3O4@ZnO/N-RGO, Fe3O4@ZnO/RGO, Fe3O4@ZnO, and ZnO. Furthermore, the performance of the photocatalyst has been studied for 5 consecutive reactions and... 

In the present research the methods and challenges to ocular drug delivery have been investigated with more emphasis on ocular diseases that do not have any approved treatment. Periocular route is a promising alternative to the common routes of ocular drug delivery especially for treatment of posterior eye diseases. Based on barriers for efficient drug delivery to the eye, magnetic drug targeting revealed to be influential to eliminate some obstacles of this route which has not been worked before. It is hypothesized that the particles can pulled into the eye or will be trapped inside the sclera tissue or even if it is not happened, they can stay behind the sclera and magnetic force can... 

Cancer is one of the most important problems that affects public health. If this disease is diagnosed quickly in the patient's body, it can be prevented and treated by determining the stage of the disease and establishing a treatment protocol. Magnetic resonance imaging (MRI) and fluorescence imaging (FI) are among the imaging methods. In order to increase the contrast of images, researchers have turned to the synthesis of materials under contrast agents, which improve diagnostic sensitivity. Synthesis of nanoparticles as multi-mode contrast agents can enhance imaging methods. In this research, the synthesis and characterization of the multifunctional Fe3O4-Mn3O4-LCysteine@g-C3N4 QDs system... 

As one of the most important agglomeration methods, pelletizing has a very important place in the iron and steel production chain. In the present study, the feasibility of improving FeO index in the final product of Pellet Factory No.1 of GolEGohar Mining and Industrial Company was investigated. The remaining FeO in the iron oxide pellet represents the amount of Magnetite that was not oxidized during the pelletizing process. The remaining FeO in the primary Magnetite is a disturbing structure for the direct reduction process and will cause a decrease in the compressive strength of the pellet (CCS) and as a result it will be crushed. Therefore, the percentage of the remaining FeO in the... 

As contrast enhancement agent, two different structures of superparamagnetic nanoparticles were synthesized. Iron oxide nanoparticles were prepared through an alkaline coprecipitation method of Iron (II) and (III) ions. PEG-6000 was used as biocapping material and its effect on particle size, colloidal stability and cytotoxicity was evaluated. On the other hand, novel core/shell structures were produced by NaBH4 reduction process of iron (III) in an aqueous media following by further oxidation by two different methods using (CH3)3NO oxygen transferring agent and exposure to oxygen flow. In both cases, structural examinations were conducted via X-ray diffraction, electron microscopy and... 

Superparamagnetic iron oxide nanoparticles (SPION) with proper surface coatings are increasingly being evaluated for clinical applications such as hyperthermia, drug delivery, magnetic resonance imaging, transfection, and cell/protein separation. Since the particles with various sizes exhibit different flow rates in the same environment (same capillary size), it is essential to use particles of a desirable size for targeted drug delivery and imaging. Particles of different sizes may be exposed to different viscosities and behave differently, particularly with regard to their velocities as they move through capillaries. In the present work, SPION with different size, purity, shape and... 

In the current research, colloidal stability of two different types of coating on the surface of Superparamagnetic Iron Oxide nanoparticles (SPIONs) was studied. In the first triumph, a dual-layer coating was achieved by utilizing optimum amount of Dextran and different PEG (Poly(ethylene glycol)) concentrations which the weight ratios of iron oxide/PEG were 1/1, 2/1, 4/1, 8/1, and 16/1. Then, the presence of the coating was characterized by XRD, FT-IR, DLS and FE-SEM methods. These results together with the TGA ones revealed that as the concentration of PEG surfactant increases, the thickness of coating increases. Moreover, VSM test was performed to specify the effect of coating on the... 

Superparamagnetic Iron Oxide NPs (SPIONs) because of their multi-task capabilities (e.g. magnetic labeling, cell isolation, hyperthermiaand controlled drug release) have been recognized as one of the most promising NPs for theranosis applications.When NPs come in contact with a biological medium, the surfaces of them are covered by biomolecules (e.g., proteins, natural organic materials, and enzymes). Therefore, what a biological entity, such as cells, tissues, and organs, sees when interacting with NPs is different original pristine surface of the NPs and actually is hard protein corona. Shape of NPs has a great impact on proteins adsorb onto its surface and consequently on the way that... 

With development of nanotechnology in medicine, nanoparticles are used for detection of tumor and cancer biomarkers. Magnetic nanoparticles are widely used for therapeutic and diagnostic objectives, because of their biocompatibility, ease of preparation and strong magnetic properties. Genistein (C15H10O5) is a soy isoflavone which is used for its anti-cancer activities. It is used for inhibition of cell proliferation, cell growth, and tumor invasion. The aim of this study is to assess the impact of nano-conjugation of geinstein as chemotherapeutic agent against cancer. For preparation of typical iron oxide Nanoparticles, Magnetite nanoparticles were synthesized by coprecipitating iron (II)... 

Regarding increasing world population, air pollution and depletion of fossil fuels supplies, hydrogen production via photoelectrochemical water splitting is a promising approach for providing a clean and renewable source of energy. Hematite (α-Fe2O3), the most common natural form of iron oxide, with a suitable band gap, high stability, earth-abundant nature and low cost has been widely acknowledged as a photoanode. However, intrinsic drawbacks of hematite like low electrical conductivity, short hole diffusion length and high recombination rate of electron-hole pairs hinder its photoelectrochemical performance with high efficiency. In this research, hematite nanostructures were synthesized... 

Hydrogen is known to be a renewable and clean source of energy, which produces water vapor and zero carbon dioxide as a result of its combustion. Photoelectrochemical water splitting (PEC) could be a promising approach in order to generate hydrogen by sunlight. Hematite (α-Fe2O3), as the most abundant naturally occurring form of iron oxide with suitable band gap, low cost, high stability and nontoxicity is considered to be an ideal photoanode. However, intrinsic drawbacks of hematite including low electrical conductivity, limited hole diffusion length, and high recombination rate of electron-hole pairs restrict its photoelectrochemical performance efficiency. In the present research,... 

One of the major problems in cancer treatment is side effects of treatments. Today, scientists have developed smart nanocarrier for diagnosis and drug delivery that can circulate in the bloodstream, pass the body's immune system to kill cancer cells and attach to the cancer cells to deliver drugs, without the side effects that are in other treatments, such as chemotherapy. magnetic nanoparticles coated by biodegradable polymers are one of the smart polymers. In this study, iron oxide nanoparticles with amine group on their surface are coated by starch modified by methyl acrylate then reacted with hydrazine and hydrazide functional group is formed that can chemically be bonded with the... 

The progress and the development of various industries, pollutants derived from the agricultural and industrial processes contaminate the environment. The degradation of these pollutants have an important effect on the environment.Magnetite (Fe3O4) nanoparticles and magnetite supported on functionalized activated carbon were synthesized and characterized by different techniques such as SEM, FT-IR, XRD, BET and VSM. The catalyst activity of these nanocatalysts was evaluated by the degradation of reactive red ME4BL (RRME4BL) textile dye in heterogeneous Fenton and electro-Fenton processes as a model pollutant. The effect of several parameters such as H2O2, RRME4BL concentration, the amount of... 

The main methods have been used clinically for cancer treatment are included: surgery, chemotherapy, radiation therapy and hyperthermia. Hyperthermia (heat therapy) treatment method in which by raising the temperature of the tumor it removed. Magnetic hyperthermia is known as a kind of hyperthermia that have been represent appropriate results. In this study, using iron oxide nanoparticle coated with graphene for cancer treatment under a magnetic field of the laser. In the first stage, graphene oxide nanosheets and nanoparticles Magntayt are synthesized by chemical oxidation and co-precipitation, respectively. At the end, the nanoparticles on the substrate of graphene layer is obtained... 

A novel thermo responsive decorated system is designed by coating Fe3O4 magnetic nanoparticles with conjugated Pluronic-ATPEG copolymer incorporated into the PEG-PMDA Hydrogel for drug delivery to the cartilage tissue. Grafted copolymer was synthesized by reaction between carboxylated Pluronic and amino terminated Poly ethylene glycol (ATPEG) and confirmed by FTIR and NMR analysis. The magnetic nanoparticles were modified with the produced copolymer and characterized by TEM, HRTEM, XRD, DLS, and VSM. A typical product has 13 nm magnetic core and 105 nm hydrodynamic diameter with narrow size distribution. DLS results showed that there was an increase in size by increasing temperature from 25℃... 

Transition metal oxides and carbon based materials (especially graphene) are common electrode materials in supercapacitors. The metal oxide limitation is due to their high agglomeration and low electrical conductivity. On the other hand graphene base materials due to their unique structure as well as high electrical conductivity and high surface area increase energy storage capability. However, chemically produced graphene generally suffers from high agglomeration and re-stacking after removal from the solution and drying, g, which results in reduced electrochemical performance of graphene sheets in supercapacitors. To take full advantage of these two groups of materials, it is expected that...