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    Design of Methods for Synthesis and Immobilization of Nitrogen Ligands Such as Pyridine onto the Mesoporous Silica Nanoparticles and Design of Pharmaceutical Structures Based on Amino Acids and Carbohydrates to Inhibit Polymerase Η for the Treatment of Leukemia and their Applications In Resins and Ionic Liquids

    , Ph.D. Dissertation Sharif University of Technology Kalhor, Sepideh (Author) ; Matloubi Moghaddam, Firouz (Supervisor) ; Fattahi, Alireza (Supervisor)
    1- Mesoporous silica materials have been found to possess pore sizes ranging from 2 -10 nm alongside 2D-hexagonal and 3D-cubic structural features. The specific properties of nanoparticles of the mesoporous silica family, such as the collected size, porosity, morphology, and high chemical stability, make them among the best drug delivery systems and catalysts. Designing the catalysts with advanced structures that effectively locate the transition metals and create active centres onto the surfaces of mesoporous silica materials has attracted extraordinary attention. According to many studies, mesoporous silica materials without organic functional groups cannot be used as catalysts in chemical... 

    Expremental Studying and Thermodynamic Modeling of Separation of Amino Acids by Ionic Liquids

    , M.Sc. Thesis Sharif University of Technology Nazem, Hadi (Author) ; Ghotbi, Cyrus (Supervisor) ; Taghikhani, Vahid (Supervisor) ; Vosoghi, Manochehr (Supervisor)
    In this work, partitioning of amino acids such as glutamic acid, phenyl anine and tryptophan in aqueous and ionic liquid phases at 298.15 K and atmospheric pressure was measured. [C4mim][Tf2N] is used due can produce two phase with water rapidly. Studying the effect of liquid solution pH on amino acids partitioning shows that increasing of pH results in decreasing of amino acid partitioning coefficient. This phenomenon pertains to electrostatic interactions between cation of amino acid and anion of ionic liquid which reduces when pH increases. Considering the effect of pH, liquid-liquid equilibrium data of amino acids was obtained in a pH that owning maximum partioning coefficient. Chemical... 

    Synthesis and Study of the Interaction of Aza-Crwon Macrocyclic Ligands with Carboxylate Side Arms with Cd Salts

    , M.Sc. Thesis Sharif University of Technology Mohammadzadeh, Amir Hossein (Author) ; Ghanbari, Bahram (Supervisor)
    In the present study, the coordination chemistry of an amino acid azacrown macrocycle ligand bearing one carboxylic acid arm (MA1) was investigated by employing NMR spectroscopy, crystallography and computational chemistry. MA1 was synthetized by the reaction of chloroacetic acid with the parent azacrown macrocycle and its purity was confirmed with 13C and 1H NMR for the first time. A new MA1 homologue, MA3 was also successfully prepared and characterized with NMR, mass spectrometry, and elemental analysis. NMR studies showed that MA1 binds to cadmium via the carboxylate arm in solution. Crystallographic studies showed that MA1 formed a one-dimensional polymer with cadmium, wherein the... 

    , M.Sc. Thesis Sharif University of Technology GHasemi Toosi, Faeze (Author) ; Ghanbari, Bahram (Supervisor)
    The purpose of this project is the synthesis and characterization of a group of phenolic amino acidic derivatives that are studied in both solid phases as well as their solutions. For this, new phenol derivatives of serin and isoleucine amino acids were synthesized and characterized by 1H NMR , 13C NMR, IR spectroscopy as well as elemental analysis. These ligands were utilized to prepare LSF perovskite membrane. According to their XRD patterns, it was concluded that the powdered precursor prepared by serin derivative has shown better qualification and less intermediate phase in the synthesized perovskite membrane similar to the sample prepared by applying EDTA. Furthermore, in the previous... 

    Computational Design of Novel Medicines as Inhibitors in Case of Cancer and Autoimmune Disease Treatment Based on Amino Acid and Sugar

    , M.Sc. Thesis Sharif University of Technology Feghhi, Razieh (Author) ; Fattahi, Alireza (Supervisor)
    SHP2 has been reported as a critical non-receptor phosphatase enzyme that plays crucial roles in numerous disorders like cancer. The previous studies on this enzyme showed that inhibiting the action of the enzyme comes as a way of controlling enzyme activity. SHP099 was discovered as an Allosteric inhibitor of the enzyme with the most inhibitory effect among all of the studied compounds. In this study we aimed to design novel dipeptide-and sugar-based inhibitors for the allosteric binding site of this enzyme with in-silico studies including docking, molecular dynamic simulation, and free binding energy analysis. Our novel designed drugs possess enough binding properties, low toxicity, and... 

    Synthesis of Amino Acids Schiff Base Complexes of Gadolinium and Study of Their Interaction with BSA

    , M.Sc. Thesis Sharif University of Technology Abedi, Najmeh (Author) ; Mohammadi Boghaei, Davar (Supervisor)
    Salicylaldehyde-amino acid Schiff base complexes are used as non-enzymatic models for the metal-pyridoxal (Vitamin B6) amino acid Schiff base systems which are key intermediates in many metabolic reactions of amino acids catalyzed by enzymes which require pyridoxal as a cofactor (transamination, decarboxylation, α and β elimination, racemization, etc.). In addition, complexes of amino acid Schiff bases are considered to constitute new kinds of potential anticancer, antitumor, antiradical and antibacterial reagents. On the other hand nuclear magnetic resonance imaging (MRI), has become a powerful tool for clinical diagnostics thanks to the development of a new class of pharmaceuticals... 

    Design a New Sugar- amino Acid-based Drug Structure as an Alternative to Methotrexate, with the Aim of Treating Leukemia and some Autoimmune Diseases

    , M.Sc. Thesis Sharif University of Technology Shapouri, Amin Mohammad (Author) ; Fattahi, Alireza (Supervisor)
    This project aims to design a drug to fight leukemia and some autoimmune diseases having few side effects. These drugs are composed of natural sugar and amino acid structures. Among the various treatments available, drug structures as inhibitors of enzymes involved in cancer-related cellular processes is an important treatment. Methotrexate is one of the most widely used anticancer drugs in the last half-century and treats leukemia and many autoimmune diseases such as psoriasis. It is a derivative of folic acid (vitamin B9) and one of the drugs with specific properties. It is an anti-folate whose anti-metabolic effects can help kill cancer cells. One of the problems with using this drug to... 

    Expression and Purification of Amyloid Beta Recombinant Peptide and the Effecs of Ultrasmall Peptides Enriched in Branch Chain Amino Acids as Inhibitors in Amyloid Formation

    , M.Sc. Thesis Sharif University of Technology Rezaei Adariani, Soheila (Author) ; Kalhor, Hamid Reza (Supervisor)
    Nowdays, it has been shown that protein misfolding is involved in more than forty diseases including Alzheimer’s and Parkinson’s. Alzheimer’s disease is one of the most common neurodegenerative diseases that disrupts brain function. The main cause of this illness is due to formation of extracellular amyloid plaque from a 42-amino acid-peptide called amyloid beta. Amyloidosis is caused by missfolding of peptides and proteins mainly because of physical and chemical changes in biomolecule or their environment.
    Therefore, in this dissertation, using synthetic and recombinant abeta peptide, kinetic of amyloidosis was examined. Ultrasmall peptides (three-amino acid), containing branched chain... 

    , M.Sc. Thesis Sharif University of Technology Rahmani, Atefeh (Author) ; Gholami, Mohammad Reza (Supervisor)
    Nanosized CdS coupled TiO2 nanocrystals were prepared by a microemulsion-mediated Hydrothermal method at relatively low temperatures. Modification of this nanocomposite with Tyrosine,Phenylalanine,Glysine and Glutamate ,especially Tyrosine resulted in enhanced photocatalytic degradation rate of Nitrobenzene( NB ) compared to using CdS-TiO2 under visible light irradiation. The prepared samples were characterized by BET,SEM, XRD, UV–Vis spectroscopy ,FTIR .It was found which have high surface area about 470 m2 g−1 and mesoporous character with the average pore diameter of 2.8 nm.The results showed this nanocomposite consisted of uniform anatase TiO2 with highly dispersed cubic phase CdS... 

    Synthesis and Application of Aminophenolic Ligands in Preparation of Perovskite-type Inorganic Membranes

    , M.Sc. Thesis Sharif University of Technology Hajibabaei Najafabadi, Hamed (Author) ; Ghanbari, Bahram (Supervisor)
    Inorganic membranes are a group of compounds which are used in gas separations such as isolating of oxygen from air and/or in petrochemical process like OCM, POM. These days, a variety of research is being conducted to synthesize these membranes from perovskite structures with formulation of ABO3. These compounds have various production procedures and various final perovskite compounds. The purpose of this project is to synthesis and identification of a group of phenolic amino acidic derivatives as new chelating agents, and their use in synthesis of perovskite membranes. For this, novel phenol derivatives of glycine, alanine, β- alanine and leucine amino acids were synthesized and... 

    Gold Electroless from Sulfite-thiosulfate Bath

    , M.Sc. Thesis Sharif University of Technology Jahanianfar, Hooman (Author) ; Dolati, Abolghasem (Supervisor)
    Gold coatings due to their unique properties, use in a wide range of applications.Decorative coatings of gold for centuries, has been considered.However, few studies have been done on the properties of this metal, this metal is shown not only in terms of decorating, but in the industry also has a wide range of applications. In this project non-cyanide electroless bath based on binary complex sulfite-thiosulfate was prepared and metal ion concentration of the complex components, temperature, time, pH and addition of amino acids, optimzed bystability, qualityand rate of coating. The main aim of optimizing bathsis optimize the thickness and appearance of the coating.It was found that by... 

    Preparation of Thin-Film Nanocomposite Membranes Based on Metal-Organic Frameworks (Mofs) and Study of their Performance in Forward Osmosis (Fo) Process

    , Ph.D. Dissertation Sharif University of Technology Bayrami, Arshad (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    The forward osmosis (FO) process is a high potential emerging membrane process in the seawater desalination and contaminated water treatment fields. One of the main challenges facing this process is the weak separation (high reverse solute flux, low water flux, and insufficient selectivity) and antifouling performances of its membranes. Various sections of this study focus on the development of FO membranes and their performance improvement. For this purpose, thin-film composite membranes with the same combination of polyethersulfone/polyamide (PES/PA) have been used to investigate the effect of metal-organic frameworks (MOFs) introduction on their performance. The support layer in all cases... 

    Site-specific protein conjugation onto fluorescent single-walled carbon nanotubes

    , Article Chemistry of Materials ; Volume 32, Issue 20 , 2020 , Pages 8798-8807 Zubkovs, V ; Wu, S. J ; Rahnamaee, S. Y ; Schuergers, N ; Boghossian, A. A ; Sharif University of Technology
    American Chemical Society  2020
    Semiconducting single-walled carbon nanotubes (SWCNTs) are among the few photostable optical emitters that are ideal for sensing, imaging, drug delivery, and monitoring of protein activity. These applications often require strategies for immobilizing proteins onto the nanotube while preserving the optical properties of the SWCNTs. Site-specific and oriented immobilization strategies, in particular, offer advantages for improving sensor and optical signaling responses. In this study, we demonstrate site-specific protein immobilization of a model of enhanced yellow fluorescent protein with a single engineered cysteine residue, using either single-stranded DNA or a pyrene-containing linker to... 

    Protein- and homo poly(amino acid)-based hydrogels with super-swelling properties

    , Article Polymers for Advanced Technologies ; Volume 20, Issue 8 , 2009 , Pages 655-671 ; 10427147 (ISSN) Zohuriaan Mehr, M. J ; Pourjavadi, A ; Salimi, H ; Kurdtabar, M ; Sharif University of Technology
    The use of super-swelling polymers is steadily increasing and the applications in industry are continuing to grow. With the authorization of the superabsorbents in food packaging by the Food and Drug Administration recently, demand may soon take off in the market. However, the increase in prices of petroleum products in recent years may be a drawback for these acrylic-based materials. Thus, there is now a need to develop natural-based super-swelling hydrogels which are more economical and environment friendly. In addition, the super-swelling gels are promising novel functions in the biomedical and pharmaceutical applications. This review is aimed to highlight research and trends in protein-... 

    Boron nitride nanotube as an antimicrobial peptide carrier: A theoretical insight

    , Article International Journal of Nanomedicine ; Volume 16 , 2021 , Pages 1837-1847 ; 11769114 (ISSN) Zarghami Dehaghani, M. Z ; Bagheri, B ; Yousefi, F ; Nasiriasayesh, A ; Mashhadzadeh, A. H ; Zarrintaj, P ; Rabiee, N ; Bagherzadeh, M ; Fierro, V ; Celzard, A ; Saeb, M. R ; Mostafavi, E ; Sharif University of Technology
    Dove Medical Press Ltd  2021
    Introduction: Nanotube-based drug delivery systems have received considerable attention because of their large internal volume to encapsulate the drug and the ability to penetrate tissues, cells, and bacteria. In this regard, understanding the interaction between the drug and the nanotube to evaluate the encapsulation behavior of the drug in the nanotube is of crucial importance. Methods: In this work, the encapsulation process of the cationic antimicrobial peptide named cRW3 in the biocompatible boron nitride nanotube (BNNT) was investigated under the Canonical ensemble (NVT) by molecular dynamics (MD) simulation. Results: The peptide was absorbed into the BNNT by van der Waals (vdW)... 

    Biomimetic proteoglycan nanoparticles for growth factor immobilization and delivery

    , Article Biomaterials Science ; Volume 8, Issue 4 , 2020 , Pages 1127-1136 Zandi, N ; Mostafavi, E ; Shokrgozar, M. A ; Tamjid, E ; Webster, T. J ; Annabi, N ; Simchi, A ; Sharif University of Technology
    Royal Society of Chemistry  2020
    The delivery of growth factors is often challenging due to their short half-life, low stability, and rapid deactivation. In native tissues, the sulfated residual of glycosaminoglycan (GAG) polymer chains of proteoglycans immobilizes growth factors through the proteoglycans'/proteins' complexation with nanoscale organization. These biological assemblies can influence growth factor-cell surface receptor interactions, cell differentiation, cell-cell signaling, and mechanical properties of the tissues. Here, we introduce a facile procedure to prepare novel biomimetic proteoglycan nanocarriers, based on naturally derived polymers, for the immobilization and controlled release of growth factors.... 

    AntAngioCOOL: computational detection of anti-angiogenic peptides

    , Article Journal of Translational Medicine ; Volume 17, Issue 1 , 2019 ; 14795876 (ISSN) Zahiri, J ; Khorsand, B ; Yousefi, A. A ; Kargar, M. J ; Shirali Hossein Zade, R ; Mahdevar, G ; Sharif University of Technology
    BioMed Central Ltd  2019
    Background: Angiogenesis inhibition research is a cutting edge area in angiogenesis-dependent disease therapy, especially in cancer therapy. Recently, studies on anti-angiogenic peptides have provided promising results in the field of cancer treatment. Methods: A non-redundant dataset of 135 anti-angiogenic peptides (positive instances) and 135 non anti-angiogenic peptides (negative instances) was used in this study. Also, 20% of each class were selected to construct an independent test dataset (see Additional files 1, 2). We proposed an effective machine learning based R package (AntAngioCOOL) to predict anti-angiogenic peptides. We have examined more than 200 different classifiers to build... 

    Structural stability and sustained release of protein from a multilayer nanofiber/nanoparticle composite

    , Article International Journal of Biological Macromolecules ; Volume 75 , April , 2015 , Pages 248-257 ; 01418130 (ISSN) Vakilian, S ; Mashayekhan, S ; Shabani, I ; Khorashadizadeh, M ; Fallah, A ; Soleimani, M ; Sharif University of Technology
    Elsevier  2015
    The cellular microenvironment can be engineered through the utilization of various nano-patterns and matrix-loaded bioactive molecules. In this study, a multilayer system of electrospun scaffold containing chitosan nanoparticles was introduced to overcome the common problems of instability and burst release of proteins from nanofibrous scaffolds. Bovine serum albumin (BSA)-loaded chitosan nanoparticles was fabricated based on ionic gelation interaction between chitosan and sodium tripolyphosphate. Suspension electrospinning was employed to fabricate poly-e{open}-caprolacton (PCL) containing protein-loaded chitosan nanoparticles with a core-shell structure. To obtain the desired scaffold... 

    Influence of Substrate, Additives, and Pulse Parameters on Electrodeposition of Gold Nanoparticles from Potassium Dicyanoaurate

    , Article Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science ; Volume 46, Issue 6 , December , 2015 , Pages 2584-2592 ; 10735615 (ISSN) Vahdatkhah, P ; Sadrnezhaad, S. K ; Sharif University of Technology
    Springer Boston  2015
    Gold nanoparticles (AuNPs) of less than 50 nm diameter were electrodeposited from cyanide solution by pulsating electric current on modified copper and indium tin oxide (ITO) films coated on glass. Morphology, size, and composition of the deposited AuNPs were studied by X-ray photoelectron spectroscopy, atomic force microscopy, and field emission scanning electron microscopy. Effects of peak current density, pulse frequency, potassium iodide and cysteine on grain size, and morphology of the AuNPs were determined. Experiments showed that cathode current efficiency increases with the pulse frequency and the iodide ion. Size of the AuNPs increased with the current density. The number of... 

    Designed amino acid feed in improvement of production and quality targets of a therapeutic monoclonal antibody

    , Article PLoS ONE ; Volume 10, Issue 10 , October , 2015 ; 19326203 (ISSN) Torkashvand, F ; Vaziri, B ; Maleknia, S ; Heydari, A ; Vossoughi, M ; Davami, F ; Mahboudi, F ; Sharif University of Technology
    Public Library of Science  2015
    Cell culture feeds optimization is a critical step in process development of pharmaceutical recombinant protein production. Amino acids are the basic supplements of mammalian cell culture feeds with known effect on their growth promotion and productivity. In this study, we reported the implementation of the Plackett-Burman (PB) multifactorial design to screen the effects of amino acids on the growth promotion and productivity of a Chinese hamster ovary DG-44 (CHO-DG44) cell line producing bevacizumab. After this screening, the amino acid combinations were optimized by the response surface methodology (RSM) to determine the most effective concentration in feeds. Through this strategy, the...