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silane-derivative
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Carbosilane dendrimers: Drug and gene delivery applications
, Article Journal of Drug Delivery Science and Technology ; Volume 59 , 2020 ; Ahmadvand, S ; Ahmadi, S ; Fatahi, Y ; Dinarvand, R ; Bagherzadeh, M ; Rabiee, M ; Tahriri, M ; Tayebi, L ; Hamblin, M. R ; Sharif University of Technology
Editions de Sante
2020
Abstract
Carbosilane dendrimers are a particular type of dendrimer structure that has been used as delivery vehicles for drugs and nucleic acids. They have a defined structure according to their generation number, and their terminal groups can be rendered cationic or anionic. The cationic charges can address the limitation of electrostatic repulsion between the negatively charged phosphate groups of nucleic acids and negatively charged cell membranes. Specific drugs can be loaded into the central part of the dendrimer or attached at the exterior, and the overall positive charge may improve the efficacy of anti-inflammatory drugs. One promising feature of dendrimers is their non-toxicity both in vitro...
Oxidative deprotection of silylethers, acetals and ketals by oxygen or air in presence of manganese and cobalt salts of 4-aminobenzoic acid supported on silica gel as catalyst
, Article Synthetic Communications ; Volume 30, Issue 10 , 2000 , Pages 1857-1863 ; 00397911 (ISSN) ; Kalantari, F ; Sharif University of Technology
Marcel Dekker Inc
2000
Abstract
Oxidative deprotection of silylethers, acetals and ketals, to their corresponding alcohols, aldehydes and ketones have been achieved using oxygen or air in the presence of cobalt and manganese salts of 4-aminobenzoic acid supported an silica gel as catalysts. Reactions are clean and catalysts can be recovered easily and reused repeatedly
Silane functionalization of nanodiamond for polymer nanocomposites-effect of degree of silanization
, Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 506 , 2016 , Pages 254-263 ; 09277757 (ISSN) ; Shojaei, A ; Sharif University of Technology
Elsevier B.V
2016
Abstract
The silanization of nanodiamond (ND) was successfully carried out by using the esterification reaction of hydrolyzed vinyltrimethoxysilane (VTS) in alcoholic solution. The surface carboxylic group of ND was first enhanced by thermal oxidation to increase the degree of esterification reaction. The extent of silane functionalization of ND was controlled by varying the weight ratio of VTS and oxidized ND (oxND), from 2:1 to 10:1 (w/w) in the functionalization reaction medium. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) revealed that the highest degree of silanization occurred at VTS/oxND of 5:1 (w/w), while more silane concentrations resulted in...
Amine/phenyl gradient derived base layer as a comprehensive extractive phase for headspace cooled in–tube microextraction of volatile organic compounds in saliva
, Article Journal of Pharmaceutical and Biomedical Analysis ; Volume 191 , 2020 ; Bagheri, H ; Rostami, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A gradient derived base layer extractive phase was synthesized and applied for the determination of volatile organic compounds (VOCs) in saliva samples using the headspace cooled in–tube microextraction (HS–CITME) method. The base layers from three different sols of phenyltriethoxysilane (PTES), octyltrimethoxysilane (OTMS) and methyltrimethoxysilane (MTMS) as nonpolar precursors were individually dip coated on the stainless steel wires (SSW). Then, the hydrolyzed polar precursor aminopropyltriethoxysilane (APTES) reacted with the silanol groups already formed on the surface of SSWs via controlled rate infusion (CRI) method. The presence of polar and non–polar functional groups on the...
Implementing a superhydrophobic substrate in immersed solvent–supported microextraction as a novel strategy for determination of organic pollutants in water samples
, Article Ecotoxicology and Environmental Safety ; Volume 163 , 2018 , Pages 104-110 ; 01476513 (ISSN) ; Asem Yousefi, A ; Bagheri, H ; Sharif University of Technology
Academic Press
2018
Abstract
In this research, a new approach for extraction and determination of polycyclic aromatic hydrocarbons from sea and rain water samples was developed by implementing a superhydrophobic substrate and consuming the least amount of solvent. This version of solvent–supported microextraction enabled us to perform the procedure in the immersion mode with the slightest troubles arising from water leakage into the gas chromatography. The superhydrophobic property leads to the fixation of extracting solvent on the substrate surface during water sampling. To prepare a superhydrophobic substrate, a piece of melamine foam was coated by tannic acid and silica nanoparticles using methyltrimethoxysilane and...
Biohybrid oxidized alginate/myocardial extracellular matrix injectable hydrogels with improved electromechanical properties for cardiac tissue engineering
, Article International Journal of Biological Macromolecules ; Volume 180 , 2021 , Pages 692-708 ; 01418130 (ISSN) ; Mashayekhan, S ; Baheiraei, N ; Pourjavadi, A ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Injectable hydrogels which mimic the physicochemical and electromechanical properties of cardiac tissue is advantageous for cardiac tissue engineering. Here, a newly-developed in situ forming double-network hydrogel derived from biological macromolecules (oxidized alginate (OA) and myocardial extracellular matrix (ECM)) with improved mechanical properties and electrical conductivity was optimized. 3-(2-aminoethyl amino) propyltrimethoxysilane (APTMS)-functionalized reduced graphene oxide (Amine-rGO) was added to this system with varied concentrations to promote electromechanical properties of the hydrogel. Alginate was partially oxidized with an oxidation degree of 5% and the resulting OA...
Role of precursors and coating polymers in sol-gel chemistry toward enhanced selectivity and efficiency in solid phase microextraction
, Article Analytica Chimica Acta ; Volume 742 , 2012 , Pages 45-53 ; 00032670 (ISSN) ; Piri Moghadam, H ; Ahdi, T ; Sharif University of Technology
Elsevier
2012
Abstract
To evaluate the selectivity and efficiency of solid phase microextraction (SPME) fiber coatings, synthesized by sol-gel technology, roles of precursors and coating polymers were extensively investigated. An on-line combination of capillary microextraction (CME) technique and high performance liquid chromatography (HPLC) was set up to perform the investigation. Ten different fiber coatings were synthesized in which five of them contained only the precursor and the rests were prepared using both the precursor and coating polymer. All the coatings were chemically bonded to the inner surface of copper tubes, intended to be used as the CME device and already functionalized by self-assembly...
An unbreakable on-line approach towards sol-gel capillary microextraction
, Article Journal of Chromatography A ; Volume 1218, Issue 26 , 2011 , Pages 3952-3957 ; 00219673 (ISSN) ; Piri-Moghadam, H ; Es'haghi, A ; Sharif University of Technology
2011
Abstract
In this work a novel unbreakable sol-gel-based in-tube device for on-line solid phase microextraction (SPME) was developed. The inner surface of a copper tube, intended to be used as a high performance liquid chromatography (HPLC) loop, was electrodeposited by metallic Cu followed by the self assembled monolayers (SAM) of 3-(mercaptopropyl) trimethoxysilane (3MPTMOS). Then, poly (ethyleneglycol) (PEG) was chemically bonded to the -OH sites of the SAM already covering the inner surface of the copper loop using sol-gel technology. The homogeneity and the porous surface structure of the SAM and sol-gel coatings were examined using the scanning electron microscopy (SEM) and adsorption/desorption...
Silica aerogel coated on metallic wire by phase separation of polystyrene for in–tube solid phase microextraction
, Article Journal of Chromatography A ; Volume 1500 , 2017 , Pages 69-75 ; 00219673 (ISSN) ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2017
Abstract
In this research, an attempt was made toward synthesizing a sol–gel–based silica aerogel and its subsequent coating on a copper wire by phase separation of polystyrene. Adaption of this new approach enabled us to coat the metallic wire with powder materials. The use of this method for coating, led to the formation of a porous and thick structure of silica aerogel. The coated wire was placed in a needle and used as the sorbent for in–tube solid phase microextraction of chlorobenzenes (CBs). The superhydrophobicity of sorbent on extraction efficiency was investigated by using different ratios of tetraethylorthosilicate/methyltrimethoxysilane. The surface coated with the prepared silica aerogel...
Silica nanoparticle surface chemistry: An important trait affecting cellular biocompatibility in two and three dimensional culture systems
, Article Colloids and Surfaces B: Biointerfaces ; Volume 182 , 2019 ; 09277765 (ISSN) ; Taebnia, N ; Yaghmaei, S ; Shahbazi, M. A ; Mehrali, M ; Dolatshahi Pirouz, A ; Arpanaei, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Great advantages bestowed by mesoporous silica nanoparticles (MSNs) including high surface area, tailorable pore diameter and surface chemistry, and large pore volume render them as efficient tools in biomedical applications. Herein, MSNs with different surface chemistries were synthesized and investigated in terms of biocompatibility and their impact on the morphology of bone marrow-derived mesenchymal stem cells both in 2D and 3D culture systems. Bare MSNs (BMSNs) were synthesized by template removing method using tetraethylorthosilicate (TEOS) as a precursor. The as-prepared BMSNs were then used to prepare amine-functionalized (AMSNs), carboxyl-functionalized (CMSNs) and polymeric...