79 research outputs found
Evaluation of effective parameters on fabrication of BSA nanoparticles
Coacervation technique was implemented in fabrication of BSA nanoparticle for the purpose of drug delivery system. Nanoparticle was purified with 48,800 g centrifuge, and then followed by dialysis, micro and ultra filtration. The fabricated nanoparticles were subjected to physical, morphological and biochemical characterization. The analyzed samples by SEM and AFM proved the semi-spherically shape of the particles whilst the size distribution was measured by photon correlation spectroscopy. Fourier transforms infra-red spectroscopy (FTIR) spectrum indicated that the fabricated nanoparticles were pure. The impact of various parameters upon the particle size was extensively investigated. The concentration of glutaraldehyde at fixed temperature had absolutely no significant effect on the size of particles. The affecting parameter was modeled to predict the size of nanoparticle. At low temperature (4{degree sign}C), the nanoparticle size of 89.3nm was fabricated with pure BSA concentration of 20 mg.ml-1
Synthesis and characterization of a novel Fe3O4-SiO2@Gold core-shell biocompatible magnetic nanoparticles for biological and medical applications
Objectives: The study of core-shell magnetic nanoparticles has a wide range of applications because of the unique combination of the nanoscale magnetic core and the functional shell. Characterization and application of one important class of core-shell magnetic nanoparticles (MNPs), i.e., iron oxide core (Fe3O4/¿-Fe2O3) with a silica shell and outer of gold (Fe3O4-SiO2@Gold (FSG)) in Boron Neutrons Capture Therapy (BNCT) highlighted. The main problem dealing with cancer cells is that the tumor and normal cells ones are mixed without a map of the boron accumulation. Methods: Areas specifically discussed in this report include the possibility of a FSG mediated by liposome as the boron carriers for the transfer of boron compound to tumor tissue. Furthermore, folate receptor was considered as an appropriate substrate that has great potential to attach to tumor on the surface of cancer cells. The present work aimed to study boron biodistribution in the muscle cancer animal model in Bagg Albino (BALB/c) mice employing PEGylated liposome-encapsulated FSG formulations. Results: The predetermined boron concentration was obtained to be 20-35 mg 10B/g. Samples of the tumor tissue, such as kidney, liver, lung, heart, skin, spleen, brain, stomach, and bone were taken as post-administration at different times to measure boron content by Inductively Coupled Plasma (ICP) analysis. The results showed the existence of GLUT-5 expression as an erythrocyte-type glucose transporter protein in a wide variety of tumor cells. Conclusions: Fe3O4-SiO2 nanoparticles are highly biocompatible with biological materials and gold shell also imparts the magnetic nanoparticles with many intriguing functional propertiesPeer ReviewedPostprint (published version
Carbon dioxide captured by multi-walled carbon nanotube and activated charcoal: A comparative study
this study, the equilibrium adsorption of CO2 on activated charcoal (AC) and multi-walled carbon nanotube (MWCNT) were investigated. Experiments were performed at temperature range of 298-318 K and pressures up to 40 bars. The obtained results indicated that the equilibrium uptakes of CO2 by both adsorbents increased with increasing pressure and decreasing temperature. In spite of lower specific surface area, the maximum amount of CO2 uptake achieved by MWCNT at 298K and 40 bars were twice of CO2 capture by AC (15 mmol.g-1 compared to 7.93 mmol.g-1). The higher CO2 captured by MWCNT can be attributed to its higher pore volume and specific structure of MWCN T such as hollowness and light mass which had greater influence than specific surface area. The experimental data were analyzed by means of Freundlich and Langmuir adsorption isotherm models. Following a simple acidic treatment procedure increased marginally CO2 capture by MWCNT over entire range of pressure, while for AC this effect appeared at higher pressures. Small values of isosteric heat of adsorption were evaluated based on Clausius-Clapeyron equation showed the physical nature of adsorption mechanism. The high amount of CO2 capture by MWCNT renders it as a promising carrier for practical applications such as gas separation
Melissa officinalis extraction with nanoencapsulation By chitosan as an ecofriendly compound
The bioactive compounds in extracts are prone to degradation by oxidation, heat, or light. Nanoencapsulation is one of the best techniques to keep the properties of these chemical compounds. The aim of this study was the extraction of Melissa officinalis (MO) and nanoencapsulation of the extract via chitosan as a biodegradable polymer. In this research, extraction of MO was investigated using various extraction methods and nanoencapsulation with MO extract was carried out via ionic gelation technique. The effectiveness of the extracts was evaluated by measuring the total phenolic content (TPC), antioxidant activity, and extraction efficiency of the solid contents. The highest efficiency was achieved for microwave-assisted extraction with the utmost values in each parameter. (TSC) was 22.81% and amounts of the TPC and antioxidant activity were 311.94 mg Gallic acid and 36 mg diphenyl picryl hydrazyl (DPPH) per 1g of the plant, respectively. Morphology study by field emission scanning electron microscopy (FE-SEM) indicated spherical shape nanoparticles with a diameter of 25nm. The size of the nanoparticles was evaluated by the Dynamic Light Scattering (DLS) technique for various concentrations of the used extracts in the encapsulation process. For 1.0, 3.0, and 5.0 mg /mL concentration, mean diameters were 24, 118, and 145 nm, respectively. Results indicated that microwave-assisted extraction was the best extraction method for MO and the encapsulation of MO extract could be created successfully with different particle sizes for the protection of bioactive compounds. Since MO is a beneficial herbal plant, the development of this research is recommended
Morphological Study of Hybrid Nanofibers Based on Polyaniline/Carbon Nanofibers Prepared by Electrospinning Method
Uniform and thin polyaniline/carbon nanofiber (PANi/CNF) hybrid nanofibers has been prepared using electrospinning method. Three polymer solutions with different components were examined for synthesis of PANi/CNF electrospun nanofibers. The SEM technique and FT-IR analysis were used to characterize the hybrid nanofibers. Effects of process parameters and used materials on the morphology and diameter of PANi/CNF hybrid nanofibers were experimentally studied in the each of polymer solutions. The resulting nanofibers obtained from the polymer solution containing commercial PANi with combination of dichloroacetic acid (DCAA) and 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPSA) were more uniform and thinner than prepared fibers from other polymer solutions. The average diameter of synthesized hybrid nanofibres using the polymer solution containing AMPSA/DCAA was about 100 nm
EIDA: An Energy-Intrusion aware Data Aggregation Technique for Wireless Sensor Networks
Energy consumption is considered as a critical issue in wireless sensor networks (WSNs). Batteries of sensor nodes have limited power supply which in turn limits services and applications that can be supported by them. An efcient solution to improve energy consumption and even trafc in WSNs is Data Aggregation (DA) that can reduce the number of transmissions. Two main challenges for DA are: (i) most DA techniques need network clustering. Clustering itself is a time and energy consuming procedure. (ii) DA techniques often do not have ability to detect intrusions. Studying to design a new DA technique without using clustering and with ability of nding intrusion is valuable. This paper proposes an energy-intrusion aware DA Technique (named EIDA) that does not need clustering. EIDA is designed to support on demand requests of mobile sinks in WSNs. It uses learning automata for aggregating data and a simple and effective algorithm for intrusion detection. Finally, we simulat
Synthesis and characterization of nanostructured polythiophene in aqueous medium by soft-template method
Polythiophene is a standout amongst the most valuable sorts of the conducting polymers that hold numerous odd physical and electrical lands for instance dissolvability, electrical conductivity and develop the ecologically and thermally stable materials. Distinctive assembling techniques have been advanced for conducting polymer nanostructures and near them, template method is a facile and encouraging method. Nanostructured polythiophene was prepared by soft-template method in the vicinity of sodium dodecyl sulfate (SDS) as an anionic surfactant, triethanolamine (TEA) as a co-surfactant and ammonium persulfate (APS) as an oxidant in aqueous medium. Moreover, the chemical structure of fabricated nanostructured polythiophene was investigated by fourier transform infrared (FTIR) spectroscopy. The morphology and particle size of the product was studied by scanning electron microscope (SEM) and atomic force microscope (AFM). Furthermore, dispersion state of nanostructured polythiophene in organic solvents was studied after being dried. The results indicate that nano-product has a favorable fiber-like-structure with a diameter in the range of 85â100 nm
Human chorionic gonadotropin attenuates amyloid-β plaques induced by streptozotocin in the rat brain by affecting cytochrome c-ir neuron density
Objective(s): Amyloid β plaques, in Alzheimer’s disease, are deposits in different areas of the brain such as prefrontal cortex, molecular layer of the cerebellum, and the hippocampal formation. Amyloid β aggregates lead to the release of cytochrome c and finally neuronal cell death in brain tissue. hCG has critical roles in brain development, neuron differentiation, and function. Therefore, we investigated the effect of hCG on the density of the congophilic Aβ plaque and cytochrome c-ir neurons in the hippocampus, prefrontal cortex, and cerebellum of Streptozotocin (STZ)-treated rats. Materials and Methods: Alzheimer model in rats (except the control group) was induced by streptozotocin (3 mg/kg, Intracerebroventricularly (ICV)). Experimental group rats received streptozotocin and then different doses of hCG (50, 100, and 200 IU, intraperitoneally) for 3 days. 48 hr after last drug injection and after histological processing, the brain sections were stained by congo red for congophilic amyloid β plaques and cytochrome c in the hippocampus, prefrontal cortex, and cerebellum were immunohistochemically stained. Results: Density of congophilic Aβ plaques and cytochrome c-immunoreactive neurons was significantly higher in ICV STZ treated rats than controls. Treatment with three doses of hCG significantly decreased the density of congophilic Aβ plaques and cytochrome c-immunoreactive neurons in the rat hippocampus, prefrontal cortex, and cerebellum in ICV STZ-treated rats (
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