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    Synthesis of Aza-Crown Macrocyclic Ligand Appended with Side Arms and Study of their Coordination and Supramolecular Chemistry with Cu2+ and C60

    , M.Sc. Thesis Sharif University of Technology Rezvanifar, Maryam (Author) ; Ghanbari, Bahram (Supervisor)
    In the present study, the coordination chemistry of an O4N4-tetrabenza-crown ether macrocyclic ligand L1 with M2+ (M= Cu, Cd, Hg, and Pb) was investigated by employing UV-visible, 1H-NMR spectroscopy in their solutions. According to the association constants calculated by 1H-NMR titrations, the complex formation stability for these closed shell cations was found in a series of Pb > Hg > Cd, leading to the larger cation, the better accommodation with L1. Moreover, the supramolecular interaction of L1 with fullerene C60 was also assessed by UV-visible spectroscopy. Meanwhile, the structure of [Cd(1)]2+ complex was determine by X-ray crystallographic method in their solid state. A square... 

    Synthesis and Characterization of NxOy-Naphthodiazacrowns and Study of Supramolecular Chemistry with C60 and Cu(II)

    , M.Sc. Thesis Sharif University of Technology Jamjah, Ali (Author) ; Ghanbari, Bahram (Supervisor)
    New N4O6 molecular tweezers were synthesized from N2O2 benzo- and naphthodiazacrown macrocycles bearing benzylic dialdehydes as a flexible and semi-flexible spacer in a short time and at room temperature. The products were characterized by IR, 1H and 13C NMR spectroscopy as well as elemental microanalysis. The interactions of some of these tweezers with C60, Cu(II), Co(II), Ni(II), Zn(II), Hg(II) and Mn(II) were investigated by employing UV-Vis and fluorescence spectroscopy. Efficient fluorescence responses for 2NM3BD were observed in the presence of C60, Cu(II), Mn(II), Hg(II) and Zn(II). Meanwhile, the calculation of the association constants (K¬BH) employing Benesi-Hildebrand equation in... 

    Chitosan based supramolecular polypseudorotaxane as a pH-responsive polymer and their hybridization with mesoporous silica-coated magnetic graphene oxide for triggered anticancer drug delivery

    , Article Polymer (United Kingdom) ; Volume 76 , October , 2015 , Pages 52-61 ; 00323861 (ISSN) Pourjavadi, A ; Mazaheri Tehrani, Z ; Jokar, S ; Sharif University of Technology
    Elsevier Ltd  2015
    Chitosan based polyseudorotaxane was designed as a pH-responsive supramolecular polymeric shell around the mesoporous silica-coated magnetic graphene oxide (Fe3O4@GO@mSiO2). It was used for doxorubicin delivery at cancerous tissue in a controlled manner. The core-shell nanocarrier was formed due to electrostatic interaction between chitosan and carboxylated surface of Fe3O4@GO@mSiO2. The maximum release occurred at pH 5.5 (pH of endosomes) because the shell collapsed at this pH. The drug nanocarrier has potential application in tumor therapy due to good pH-sensitive behavior, improved solubility and high colloidal stability in... 

    Synthesis and photoisomerization study of new aza-crown macrocyclic tweezer tethered through an azobenzene linker: the first report on supramolecular interaction of azobenzene moiety with C60

    , Article Journal of Molecular Structure ; Volume 1144 , 2017 , Pages 360-369 ; 00222860 (ISSN) Ghanbari, B ; Mahdavian, M ; García Deibe, A. M ; Sharif University of Technology
    In the present communication, three bimacrocyclic tweezers linked through azobenzene moiety, Ln (n = 1–3) were synthesized in a multistep route and characterized by x-ray crystallography, IR, 1H and 13C NMR, UV–vis spectroscopy as well as CHN microanalysis. UV–visible spectroscopy established that the irradiation of L1 and L3 with UV light promoted the trans to cis isomerization. Irradiating the reaction mixtures with Hg lamp, significant supramolecular interactions between L1 and L3 with C60 were also found in terms of the association constants calculated by UV–visible spectroscopy, denoting on more pronounced interaction with C60 that in the absence of UV light. The molecular structures of... 

    Synthesis of water dispersible reduced graphene oxide via supramolecular complexation with modified β-cyclodextrin

    , Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 66, Issue 5 , 2017 , Pages 235-242 ; 00914037 (ISSN) Pourjavadi, A ; Eskandari, M ; Hosseini, S. H ; Nazari, M ; Sharif University of Technology
    Taylor and Francis Inc  2017
    A noncovalent functionalization of the edges of reduced graphene oxide (RGO) with β-cyclodextrin-graft-hyperbranched polyglycerol (β-CD-g-HPG) was successfully performed via a host-guest interaction. The results showed that β-CD-g-HPG disperses the graphene sheets better than pure β-CD or HPG. The resulted supramolecular structure is stable in neutral water medium more than one week. However, in acidic medium the host-guest interaction is collapsed and graphene nanosheets precipitate. © 2017, Copyright © Taylor & Francis  

    Fully supramolecular vesicles as anticancer drug delivery systems

    , Article New Journal of Chemistry ; Volume 37, Issue 2 , 2013 , Pages 295-298 ; 11440546 (ISSN) Pourjavadi, A ; Adeli, M ; Yazdi, M ; Sharif University of Technology
    A supramolecular linear-dendritic copolymer consisting of a polystyrene backbone and hanging hyperbranched polyglycerols was prepared and characterized. Host-guest interactions between β-cyclodextrin incorporated in the core of polyglycerol as a host and aromatic rings of polystyrene as guests lead to the formation of a supramolecular linear-dendritic copolymer. Supramolecules formed micelles in aqueous solutions which were able to encapsulate and transfer paclitaxel with a high loading capacity  

    Supramolecular self-assembly of oleylamide into organogels and hydrogels: a simple approach in phase selective gelation of oil spills

    , Article Soft Materials ; Volume 18, Issue 1 , 2020 , Pages 55-66 Eftekhari Sis, B ; Bagheri, A ; Younesi Araghi, H ; Akbari, A ; F. Paige, M ; Sharif University of Technology
    Taylor and Francis Inc  2020
    A new gelator based of oleylamide has been introduced, which was gelled nonpolar hydrocarbon and CCl4 solvents through self-assembly. Also, the gelator formed a two-component hydrogel in combination with SDS, an anionic surfactant. UV-Vis studies revealed that the H-type and J-type aggregation of organogels in hexane and hydrogel in water, respectively. The xerogel, obtained by evaporating the solvent of organogel, selectively gelled and adsorbed oil spills on water surfaces. The effect of the various parameters, including temperature, water acidity and pH on the oil spill adsorption was studied, revealing the high ability of the xerogel to removing the oil contamination from water in up to... 

    Visual recognition of tryptophan enantiomers using chiral self assemblies of quantum dots

    , Article ACS Applied Nano Materials ; 2021 ; 25740970 (ISSN) Fahimi Kashani, N ; Jafar Nezhad Ivrigh, Z ; Bigdeli, A ; Hormozi Nezhad, M.R ; Sharif University of Technology
    American Chemical Society  2021
    Discrimination of chiral targets is generally achieved with chiral nanomaterials. However, the limited number of intrinsic chiral nanostructures as well as their complex synthesis procedure has led to the production of chirality-induced nanomaterials as alternatives. Chirality can be induced in nanomaterials by either chirality transfer or the formation of chiral assemblies. Using the latter approach, in this work, we have provided chiral supramolecular assemblies of CdTe quantum dots (QDs) from achiral starting materials. CTAB-QD assemblies showed chiroptical activities, and their orange emission in combination with the blue emission of carbon dots was utilized as a ratiometric chiral... 

    Folate-conjugated pH-responsive nanocarrier designed for active tumor targeting and controlled release of gemcitabine

    , Article Pharmaceutical Research ; Volume 33, Issue 2 , 2016 , Pages 417-432 ; 07248741 (ISSN) Pourjavadi, A ; Mazaheri Tehrani, Z ; Abedin Moghanaki, A ; Sharif University of Technology
    Springer New York LLC 
    Purpose: The prime end of this study was to design a novel pH-sensitive as well as a PEGylated dendritic nanocarrier for both controllable and traceable gemcitabine delivery to cancerous cells. To accomplish this goal, we took advantage of a hybrid of nanoparticles including: mesoporous silica, graphene oxide and magnetite. Methods: The nanocarrier was prepared in a multi-step synthesis route. First, magnetite mesoporous silica was deposited on the graphene oxide matrix. Then, polyamidoamine dendrimers (up to generation 1.5) with pentaethylene hexamine end groups were grafted on the surface of the nanoparticles. In order to enhance the biostability, and as the next step, the nanocarrier was... 

    Supramolecular polycaprolactone nanocomposite based on functionalized hydroxyapatite

    , Article Journal of Bioactive and Compatible Polymers ; Volume 27, Issue 5 , January , 2012 , Pages 467-480 ; 08839115 (ISSN) Mehmanchi, M ; Shokrollahi, P ; Atai, M ; Omidian, H ; Bagheri, R ; Sharif University of Technology
    SAGE  2012
    Arms bearing ureido-pyrimidinone functional groups with self-association capability (through quadruple hydrogen bonds) were successfully grafted onto hydroxyapatite nanoparticles. The supramolecularly modified nanoparticles (nHApUPy) exhibited enhanced colloidal stability compared to the original hydroxyapatite nanoparticles and were uniformly dispersed in supramolecular polycaprolactone in PCL(UPy)2/HApUPy nanocomposites at different filler loadings. The combined atomic force microscopy, mechanical, and rheological analyses confirmed a high degree of compatibility of HApUPy nanoparticles with the polymer matrix. The temperature dependence of the supramolecular structure in PCL(UPy)2/HApUPy... 

    Thermo- and pH-sensitive dendrosomes as bi-phase drug delivery systems

    , Article Nanomedicine: Nanotechnology, Biology, and Medicine ; Volume 9, Issue 8 , 2013 , Pages 1203-1213 ; 15499634 (ISSN) Adeli, M ; Fard, A. K ; Abedi, F ; Chegeni, B. K ; Bani, F ; Sharif University of Technology
    Fully supramolecular dendrosomes (FSD) as bi-phase drug delivery systems are reported in this work. For preparation of FSD, amphiphilic linear-dendritic supramolecular systems (ALDSS) have been synthesized by host-guest interactions between hyperbranched polyglycerol having β-cyclodextrin core and bi-chain polycaprolactone (BPCL) with a fluorescine focal point. Self-assembly of ALDSS in aqueous solutions led to FSD. They were able to encapsulate paclitaxel with a high loading capacity. The dendrosome-based drug delivery systems were highly sensitive to pH and temperature. They were stable at 20-37. °C and pH7-8, but dissociated and released drug at temperatures lower than 20. °C or higher...