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Experimental Study of Biological Synthesis, Stabilization and Delivery of the Recombinant Protein of Chondroitinase
, Ph.D. Dissertation Sharif University of Technology ; Vossoughi, Manouchehr (Supervisor) ; Alemzadeh, Iran (Supervisor) ; Khajeh, Khosro (Supervisor)
Abstract
In this research, immobilization method was employed to increase the thermal stability of Chondroitinase ABC I (cABC I) enzyme. In first step, magnetite nanoparticle (Fe3O4) was selected as a support and cABC I enzyme was attached via the adsorption method. The results showed that pH=6.5, temperature 15 ˚C, enzyme-to-support mass ratio 0.75, and incubation time 4.5 hr were the appropriate conditions for immobilizing cABC I enzyme on Fe3O4 nanoparticle. It was also found that the optimum pH for free and immobilized enzymes was 7.6 and 8.0, respectively. The maximum activity of free enzyme was obtained at 25 ˚C, whereas the activity of immobilized enzyme was almost constant in the temperature...
An investigation on the optimum conditions of synthesizing a magnetite based ferrofluid as MRI contrast agent using Taguchi method
, Article Materials Science- Poland ; Volume 31, Issue 2 , 2013 , Pages 253-258 ; 01371339 (ISSN) ; Hosseini, H. R. M ; Sharif University of Technology
2013
Abstract
In this study, some stabilized magnetite based ferrofluids were synthesized using Dextran as a stabilizing agent. In order to achieve optimum experimental conditions for synthesizing ferrofluids as MRI contrast agents, the Taguchi method was used. This approach was employed to design and minimize the number of required experiments. By using the Taguchi orthogonal (L16) array, four parameters including solution temperature and alkalinity, reaction temperature and stirring rate were selected at four predetermined levels for 16 experiments. Synthesizing processes established based on this set of experimental conditions were carried out and the obtained ferrofluids were characterized using PCS,...
Examination of chondroitinase ABC I immobilization onto dextran-coated Fe3O4 nanoparticles and its in-vitro release
, Article Journal of Biotechnology ; Volume 309 , 2020 , Pages 131-141 ; Vossoughi, M ; Khajeh, K ; Alemzadeh, I ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Chondroitinase ABC I (cABC I) has received notable attention in treatment of spinal cord injuries and its application as therapeutics has been limited due to low thermal stability at physiological temperature. In this study, cABC I enzyme was immobilized on the dextran-coated Fe3O4 nanoparticles through physical adsorption to improve the thermal stability. The nanoparticles were characterized using XRD, SEM, VSM, and FTIR analyses. Response surface methodology and central composite design were employed to assess factors affecting the activity of immobilized cABC I. Experimental results showed that pH 6.3, temperature 24 °C, enzyme/support mass ratio 1.27, and incubation time 5.7 h were the...
Colloidal stability of dextran and dextran/poly ethylene glycol coated TiO2 nanoparticles by hydrothermal assisted sol-gel method
, Article Ceramics International ; Volume 39, Issue 7 , 2013 , Pages 8377-8384 ; 02728842 (ISSN) ; Madaah Hosseini, H. R ; Faghihi Sani, M. A ; Sharif University of Technology
2013
Abstract
Colloidal stability of dextran (Dex) and Dex/poly ethylene glycol (PEG) coated TiO2 nanoparticles (NPs) were investigated. The particles were successfully synthesized by a hydrothermal assisted sol-gel technique. The results of Ultraviolet-visible (UV-vis) spectrophotometry showed that Dex and PEG additions during hydrothermal process (HTP) led to the formation of long-term (more than 60 days) stable colloids, while the addition of dispersants after HTP did not have a significant impact on the colloidal stability of NPs. X-ray diffraction (XRD) and selected area electron diffraction (SAED) analyses proved that PEG and/or Dex coated NPs had less crystallinity than the plain TiO2. Fourier...
Dextran-graft-poly(hydroxyethyl methacrylate) gels: A new biosorbent for fluoride removal of water
, Article Designed Monomers and Polymers ; Volume 16, Issue 2 , 2013 , Pages 127-136 ; 1385772X (ISSN) ; Mousavi, S. A ; Amini Fazl, A ; Amini Fazl, M. S ; Ahmari, R ; Sharif University of Technology
2013
Abstract
Synthesis of dextran-graft-poly(hydroxyethyl methacrylate) gels as a new fluoride biosorbent was considered in this work. For this propose, the Taguchi experimental design method was used for optimizing the synthetic conditions of the gels to reach high level of fluoride absorbency. The effects of three main parameters including concentrations of monomer (hydroxyethyl methacrylate), crosslinking agent (ethylene glycol dimethacrylate), and initiator (ammonium persulfate) on the final properties of the prepared gels were investigated. The proposed mechanism for grafting and chemically crosslinking reactions was proved with equilibrium water absorption, Fourier-transformed infrared, scanning...
Drug release from ion-exchange microspheres: Mathematical modeling and experimental verification
, Article Biomaterials ; Volume 29, Issue 11 , 2008 , Pages 1654-1663 ; 01429612 (ISSN) ; Wu, X. Y ; Sharif University of Technology
2008
Abstract
This paper presents for the first time a mathematical model for a mechanism of controlled drug release involving both ion exchange and transient counter diffusion of a drug and counterions. Numerical analysis was conducted to study the effect of different factors on drug release kinetics including environmental condition, material properties, and design parameters. The concentration profiles of counterions and drug species, the moving front of ion exchange, and three distinct regions inside a microsphere, namely unextracted region, ion-exchange region and drug diffusion region, were revealed by model prediction. The numerical results indicated that the rate of drug release increased with an...
Design of experiment, preparation, and in vitro biological assessment of human amniotic membrane extract loaded nanoparticles
, Article Current Pharmaceutical Biotechnology ; Volume 21, Issue 3 , 2020 , Pages 256-267 ; Atyabi, F ; Khoshayand, M. R ; Mahbod, R ; Cohan, R. A ; Akbarzadeh, I ; Bakhshandeh, H ; Sharif University of Technology
Bentham Science Publishers
2020
Abstract
Background: Human amniotic membrane grafting could be potentially useful in ocular surface complications due to tissue similarity and the presence of factors that reduce inflammation, vascu-larization, and scarring. However, considerations like donor-derived infectious risk and the requirement of an invasive surgery limit the clinical application of such treatments. Moreover, the quick depletion of bioactive factors after grafting reduces the efficacy of treatments. Therefore, in the current study, the possibility of nano delivery of the bioactive factors extracted from the human amniotic membrane to the ocular surface was investigated. Materials and Methods: Nanoparticles were prepared...
Prediction of the partition coefficients of biomolecules in polymer-polymer aqueous two-phase systems using the artificial neural network model
, Article Particulate Science and Technology ; Volume 28, Issue 1 , 2010 , Pages 67-73 ; 02726351 (ISSN) ; Taghikhani, V ; Vossoughi, M ; Sharif University of Technology
Abstract
In this work, an artificial neural network model was used to obtain the partition coefficients of biomolecules in polymer-polymer aqueous two-phase systems. In the artificial neural network, the partition coefficient of a biomolecule depends on the difference between concentrations of poly (ethylene glycol), dextran in the top and bottom phases, temperature and molecular weights of poly (ethylene glycol), dextran, and the biomolecule. The network topology is optimized and the (6-1-1) architecture is found using optimization of an objective function with sequential quadratic programming (SQP) method for 450 experimental data points. The results obtained from the neural network of the...
Histidine-enhanced gene delivery systems: The state of the art
, Article Journal of Gene Medicine ; Volume 24, Issue 5 , 2022 ; 1099498X (ISSN) ; Jahanpeimay Sabet, M ; Hasanzadeh, A ; Kamrani Mousavi, S. M ; Haeri Moghaddam, N ; Hooshmand, S. A ; Rabiee, N ; Liu, Y ; Hamblin, M. R ; Karimi, M ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Gene therapy has emerged as a promising tool for treating different intractable diseases, particularly cancer or even viral diseases such as COVID-19 (coronavirus disease 2019). In this context, various non-viral gene carriers are being explored to transfer DNA or RNA sequences into target cells. Here, we review the applications of the naturally occurring amino acid histidine in the delivery of nucleic acids into cells. The biocompatibility of histidine-enhanced gene delivery systems has encouraged their wider use in gene therapy. Histidine-based gene carriers can involve the modification of peptides, dendrimers, lipids or nanocomposites. Several linear polymers, such as polyethylenimine,...
Synthesis of pseudopolyrotaxanes-coated superparamagnetic Iron oxide nanoparticles as new MRI contrast agent
, Article Colloids and Surfaces B: Biointerfaces ; Volume 103 , March , 2013 , Pages 652-657 ; 09277765 (ISSN) ; Panahifar, A ; Adeli, M ; Amiri, H ; Lascialfari, A ; Orsini, F ; Doschak, M. R ; Mahmoudi, M ; Sharif University of Technology
2013
Abstract
Superparamagnetic Iron Oxide Nanoparticles (SPIONs) were synthesized and coated with pseudopolyrotaxanes (PPRs) and proposed as a novel hybrid nanostructure for medical imaging and drug delivery. PPRs were prepared by addition of α-cyclodextrin rings to functionalized polyethylene glycol (PEG) chain with hydrophobic triazine end-groups. Non-covalent interactions between SPIONs and PPRs led to the assembly of SPIONs@PRs hybrid nanomaterials. Measurements of the 1H Nuclear Magnetic Resonance (NMR) relaxation times T1 and T2 allowed us to determine the NMR dispersion profiles. Comparison between our SPIONs@PRs hybrid nano-compound and the commercial SPION compound, Endorem®, showed a higher...