فهرست مطالب
Nanomedicine Journal
Volume:3 Issue: 4, Autumn 2016
- تاریخ انتشار: 1395/07/15
- تعداد عناوین: 8
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Pages 202-216Over the last two decades, many researchers have developed a variety of stainless steel-based medical implant types,taking full advantage of nanostructuring technologies. In this paper the application, fabrication and development of nanostructured stainless steel based materials with new composition for medical implants will be discussed. It is well established that application of severe plastic deformation (SPD) can decrease the grain size of metals and alloys significantly to the nanometer range. Among all the available SPD methods, equal channel angular pressing (ECAP) is very applicable. Stainless Steel became the raw structural material for the majority of the developed medical implants, and several techniques had to be studied and established in order to fabricate a feasible stainless steel-based neural probe. These nanostructured implants present a superior performance mechanically, biologically and electrically, when compared to the conventional implants. Finally, the effect of alloying elements on the bio-interaction of stainless steel will be explained.Keywords: Implants, Nanostructure, Stainless steel, Severe plastic deformation (SPD)
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Pages 217-222Objective(s)Electrospun nanofibrous mats of poly(lactic acid) (PLA) and nanohydroxyapatite (nano-HA) were prepared and proliferation and differentiation of mesenchymal stem cells on the prepared nanofibers were investigated in this study.Materials And MethodsPLA/nano-HA nanofibers were prepared by electrospinning. The effects of process parameters, such as nano-HA concentration, distance, applied voltage, and flow rate on the mean diameter of electrospun nanofibers were investigated. Scanning electron microscopy (SEM) was used to determine the mean fiber diameter of produced nanofibers. Mechanical propertes of nanofibrous mats were evaluated using a universal testing machine. Response surface methodology was used to model the fiber diameter of electrospun PLA/nano-HA nanofibers.ResultsThe average fiber diameter for optimized nanofibers was 125 ± 11 nm. MTT and ALP results showed that optimization of fiber diameter increased the osteogenic differentiation of stem cells.ConclusionIt could be concluded that optimization of fiber diameter has beneficial effect on cell proliferation and differentiation. Optimized nanofibers of PLA/nano-HA could be good candidates for bone tissue engineering.Keywords: Mesenchymal stem cells, Nanofiber, Optimization
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Pages 223-229Objective(s)An efficient vaccine against TB is an urgent need. TB peptides are safe candidate but they are weak immunogens and needs to be potentiated by adjuvant/delivery systems. The main purpose of the present study was to determine the potential of CHT based NPs containing ESAT-6 antigen of M. tuberculosis for inducing mucosal and systemic immune responses after intranasal and subcutaneous injection in mice model.Materials And MethodsCHT and TMC based NPs were prepared by coating of cationic polymer on the anionic peptide by ionic gelation method and their characteristics were evaluated by scanning electron microscopy (SEM) and dynamic light scattering (DLS). Physical stability of NPs was studied within 30 days. Finally, the ability of formulated NPs to elicit immune responses in BALB/c mice were evaluated following nasal and subcutaneous immunization.ResultsThe best weight ratio of antigen to polymer (CHT or TMC) was 1:2. CHT and TMC NPs had a mean size of 356.3 ± 42.20, and 470.3 ± 48.21 nm, respectively. NPs were stable up to 15 days. CHT:ESAT-6 NPs gave higher serum IgG1 and IgG total responses and TMC:ESAT-6 NPs induced high titers of IgG2a and IFN-g.ConclusionRegards to the importance of cellular immune responses in effective protection against TB, and also the solubility in physiological pH, TMC NPs are more efficient adjuvant/antigen delivery system for immunization against TB.Keywords: Chitosan, Trimethylchitosan nanoparticles, ESAT, 6 antigen, Mycobacterium tuberculosis, Nasal immunization, Subcutaneous immunization
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Pages 230-239Objective(s)Enzyme immobilization via nanoparticles is perfectly compatible against the other chemical or biological approximate to improve enzyme functions and stability. In this study lactoperoxidase was immobilized onto silica-coated magnetite nanoparticles to improve enzyme properties in the presence of cadmium chloride as an inhibitor.Materials And MethodsThe process consists of the following steps: (1) preparing magnetic iron oxide nanoparticles using the co-precipitation method, (2) coating NP with silica (SiO2) by solgel reaction, (3) characterizations of NPs were examined by FT-IR, XRD, AGFM and TEM. (4) Immobilization of LPO on the magnetite NPs, (5) Study kinetic and stability of both free and immobilized LPO in the presence of various concentrations of cadmium chloride.ResultsThe size of the Fe3O4 and silica-coated magnetite nanoparticles were about 9 nm and 12 nm, respectively. The results showed that the highest immobilization yield, nearly 90 %, was attained at 240 to 300 µg of LPO at 15h. It was found that the concentration of cadmium chloride directly affects the LPO activity and changes the kinetic parameters of it. Also, the results showed that immobilized LPO has better tolerance than the free LPO, so that after immobilization, Vmax of immobilized LPO was increased and Km of immobilized LPO was decreased.ConclusionThe results demonstrating that the effect of immobilized lactoperoxidase on silica-coated magnetite nanoparticles increases the stability of the LPO in the presence of cadmium chloride as inhibitor. MichaelisMenten parameters (Km and Vmax) also revealed the considerable improvement of immobilized.Keywords: Cadmium chloride, Enzyme immobilization, Enzyme stability, Lactoperoxidase, Silica, coated magnetic nanoparticles
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Pages 240-247Objective(s)Chitosan nanoparticles (CNPs) were prepared based on the ionic gelation of chitoan with anionic compounds of Ocimum basilicum leaf extract.Materials And MethodsAfter addition of Ocimum basilicum leaf extract to chitosan solution, the physicochemical properties of the nanoparticles were determined by Field Emission Scanning Electron microscope (FESEM), Fourier Transform Infrared (FTIR) analysis, X-ray diffraction (XRD) Pattern, and Dynamic Light Scattering (DLS). The antibacterial activity of CNPs was evaluated by agar disc diffusion method.ResultsThe synthesized nanoparticles were found to be nearly spherical shape with size in the range of 135-729 nm. FTIR analysis revealed the presence of polyphenolic; proteins and alkaloids compounds act as effective agents for converting chitosan to CNPs. Moreover, the synthesized nanoparticles showed potent antibacterial activity against Gram positive and Gram negative bacteria.ConclusionThese results reveal that natural sources of materials such as plants could be used for preparation of CNPs instead of use of chemical substances.Keywords: Biosynthesis, Chitosan nanoparticles, Leaf extract, Ocimum basilicum
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Pages 248-252Objective(s)According to the unique properties of magnetic nanoparticles, Nickel Metal-Organic Frameworks (MOF) was synthesized successfully by ultrasound irradiation. Metal-organic frameworks (MOFs) are organicinorganic hybrid extended networks that are constructed via covalent linkages between metal ions/metal clusters and organic ligands called a linker.Materials And MethodsThe nanoparticles were synthesized by Ultrasound Method Under a synthesis conditions, All chemicals were used as received without further purification. Scanning electron microscopy (SEM) images were obtained on LEO- 1455VP equipped with an energy dispersive X-ray spectroscopy at university of Kashan in Iran. Transition electron microscopy (TEM) images were obtained on EM208 Philips transmission electron microscope with an accelerating voltage of 200 kV.ResultsResults showed that Ni-MOF synthesized by this method, had smaller particle size distribution and It was found that the different kinds of ligand leads to preparation products with different morphologies and textural properties. Moreover, ultrasound irradiation method has significant effect on microstructures of as-synthesized MOFs and can improve their textural properties compared to method without using hydrothermal route.The XRD patterns of the samples obtained from ultrasound irradiation was well matched with that of as-prepared Ni-MOF by solvothermal method.ConclusionThis rapid method of ultrasonic radiation as compared to the classical solvothermal synthesis, showed promising results in terms of size distribution, surface area, pore diameter and pore volume.Keywords: Drug carriers, Ni, MOF, Surface area, Ultrasound irradiation
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Pages 253-267Objective(s)Response surface methodology (RSM) by central composite design (CCD) was applied to statistically optimize the preparation of Rutin-Quercetin (Ru-Qr) dual drug loaded human hair keratin nanoparticles as well as evaluate the characteristics.Materials And MethodsThe effects of three independent parameters, namely, temperature (X1:10-40 C), surfactant (X2: SDS (1), SLS (2), Tween-20 (3)), and organic solvents (X3: acetone (1), methanol (2), chloroform (3)) were investigated to optimize the preparation of dual drug loaded keratin nanoparticles, and to understand the effects of dependent parameters namely, drug releasing capacity, average particle size, total antioxidant power, zeta potential, and polydispersity index of Ru-Qr nanoparticles. Optimization was executed by CCD and RSM using statistical software (Design Expert, version 8.0.7.1, Stat-Ease, Inc., Minneapolis, MN, USA). The optimal Ru-Qr dual drug loaded keratin nanoparticles were obtained at temperature (X1): 40ÚC, SDS (X2), and acetone (X3).ResultsUnder this conditions to achieve highest drug releasing capacity of 98.3%, average size of nanoparticles are 125 nm, total antioxidant power 98.68%, zeta potential 28.09 mV, and polydispersity index of 0.54. Although majority of the experimental values were relatively well matched with the predicted values.ConclusionThis optimization study could be useful in pharmaceutical industry, especially for the preparation of new nano-therapeutic formulations encapsulated with drug molecules. This nanotechnology based drug delivery system is to overcome multi drug resistance and site specific action without affecting other organs and tissues. The methodology adopted in this work shall be useful in improvement of quality of human health.Keywords: Keratin, Quercetin, Response surface methodology, Rutin
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Pages 268-279Objective(s)Binary hybrids of chitosan-zeolite have many interesting applications in separation and bacteriostatic activity.Materials And MethodsTemplate free ZSM-5 zeolite was synthesized by hydrothermal method, physical hydrogels of nano chitosan in the colloidal domain were obtained in the absence of toxic organic solvent and then nano chitosan/ZSM-5 hybrid composites with nano chitosan contents of 0.35%, 3.5%, 35% wt.% were prepared. The as prepared hybrid composites were ion-exchanged with Ag cations.ResultsXRD and FT-IR results revealed a good crystalinity of as synthesized template frees ZSM-5 with BET surface area of 307 m2g-1. Presence of chitosan in composites was confirmed by XRD patterns and FT-IR spectroscopic analysis, the chitosan content in composite was obtained with TG analysis. SEM analysis of composites shows that chitosan particles were dispersed within the nanometer scale. The antimicrobial activity of different samples was investigated and the results showed that the Ag+exchanged samples have the highest antibacterial properties. Cancer cell line A549 cell line were cultured in designated medium treated with Ag+exchanged samples at the concentration of 0.01 to 0.5 mg/ml. After 24 and 48 hours incubation, the efficacy of Ag+exchanged samples to treat cancer cell lines were measured by means of cell viability test via MTT assay. Concentrations of 0.05 and 0.1 mg/ml of Ag+exchanged samples induced a very low toxicity.ConclusionThese hybrid composite materials have potential applications on tissue engineering and antimicrobial food packaging.Keywords: Antibacterial properties, Chitosan, Cytotoxicity, Hybrid nanocomposite, Template free ZSM, 5