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physicochemical-properties
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Retina-Choroid-Sclera Permeability for Ophthalmic Drugs in the Vitreous to Blood Direction: Quantitative Assessment
, Article Pharmaceutical Research ; 2012 , Pages 1-19 ; 07248741 (ISSN) ; Abdekhodaie, M. J ; Cheng, Y. L ; Sharif University of Technology
Springer
2012
Abstract
Purpose: To determine the outward permeability of retina-choroid-sclera (RCS) layer for different ophthalmic drugs and to develop correlations between drug physicochemical properties and RCS permeability. Methods: A finite volume model was developed to simulate pharmacokinetics in the eye following drug administration by intravitreal injection. The RCS permeability was determined for 32 compounds by best fitting the drug concentration-time profile obtained by simulation with previously reported experimental data. Multiple linear regression was then used to develop correlations between best fit RCS permeability and drugs physicochemical properties. Results: The RCS drug permeabilities had...
Hydrolyzed collagen-based hydrogel with salt and pH-responsiveness properties
, Article Journal of Applied Polymer Science ; Volume 106, Issue 4 , 2007 , Pages 2371-2379 ; 00218995 (ISSN) ; Salimi, H ; Kurdtabar, M ; Sharif University of Technology
2007
Abstract
A novel hydrolyzed collagen-based hydrogel has been prepared by grafting the binary mixture of acrylamide and 2-acrylamido-2-methylpropanesulfonic acid onto the collagen backbone in the presence of a cross-linking agent. Its physicochemical properties in aqueous solution were studied. The effect of reaction variables on both gel content and swelling capacity was investigated to achieve a hydrogel with improved absorbency and gel content. The absorbency under load of optimized hydrogel was also investigated by using an absorbency under load tester at various applied pressures. The swelling ratio in various salt solutions was also determined and additionally, the swelling of hydrogels was...
Non-Destructive estimation of physicochemical properties and detection of ripeness level of apples using machine vision
, Article International Journal of Fruit Science ; Volume 22, Issue 1 , 2022 , Pages 628-645 ; 15538362 (ISSN) ; Nadimi, M ; Abbaspour Gilandeh, Y ; Paliwal, J ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Nondestructive estimation of physicochemical properties, post-harvest physiology, and level of ripeness of fruits is essential to their automated harvesting, sorting, and handling. Recent research efforts have identified machine vision systems as a promising noninvasive nondestructive tool for exploring the relationship between physicochemical and appearance characteristics of fruits at various ripening levels. In this regard, the purpose of the current study is to provide an intelligent algorithm for estimating two physical properties including firmness, and soluble solid content (SSC), three chemical properties viz. starch, acidity, and titratable acidity (TA), as well as detection of the...
Improvement of Edible Oil by Interestrification Process by Lipase
, M.Sc. Thesis Sharif University of Technology ; Alemzadeh, Iran (Supervisor) ; Razavi, Jalil (Supervisor)
Abstract
Fats and oils are one of the main human food diet components that provide the necessary fatty acids for our body. So the fatty acids available in consuming oils are so important. In this research the mixture of palm and sunflower oils with different compounds: (80:20, 60:40, 50:50, 40:60, 20:80) were used for preparing free- trans shortening by interesterification. For this purpose a special stabilized lipase (Lipozyme TLIM) were used and performed the physicochemical properties: free fatty acids, peroxide value, iodine value, slip melting point, solid fat content, P-anisidine value, soap, oxidative stability at 110 0C, and the profile of fatty acids on the primitive blends and final samples...
The effects of a hydrochloric acid pre-treatment on the physicochemical properties and pozzolanic performance of rice husk ash
, Article Cement and Concrete Composites ; Volume 39 , 2013 , Pages 131-140 ; 09589465 (ISSN) ; Khaloo, A. R ; Rajabipour, F ; Sharif University of Technology
2013
Abstract
This paper investigates the effects of acid normality (0.01-6 N HCl) and combustion retention time (0.25- 16 hours) on the pozzolanic properties of pre-combustion acid-treated rice husk ash. The pozzolanic reactivity was quantified by adding ground ash to saturated Ca(OH)2 solutions and monitoring the time-dependent electrical conductivity and pH of the solutions. Also, the strength activity of ashes from different processes was measured by testing the compressive strength of mortars. It was observed that acid treatment results in ashes with higher SiO2 content, lower alkali and unburned carbon content, better grindability, and smaller particle size, in comparison with ash from non-acid...
Determination of nanoparticles using UV-Vis spectra
, Article Nanoscale ; Volume 7, Issue 12 , Feb , 2015 , Pages 5134-5139 ; 20403364 (ISSN) ; Ghasemi, F ; Ghalkhani, M ; Ashkarran, A. A ; Akbari, S. M ; Pakpour, S ; Hormozi Nezhad, M. R ; Jamshidi, Z ; Mirsadeghi, S ; Dinarvand, R ; Atyabi, F ; Mahmoudi, M ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
Nanoparticles (NPs) are increasingly being used in different branches of science and in industrial applications; however, their rapid detection and characterization at low concentration levels have remained a challenge; more specifically, there is no single technique that can characterize the physicochemical properties of NPs (e.g. composition and size). In this work we have developed a colorimetric sensor array for defining the physicochemical properties of NPs in aqueous solution with ultra-low concentrations (e.g. 10-7g ml-1 for gold NPs). Various NPs were readily identified using a standard chemometric approach (i.e. hierarchical clustering analysis), with no misclassifications over 400...
Nanoparticle-based optical sensor arrays
, Article Nanoscale ; Volume 9, Issue 43 , 2017 , Pages 16546-16563 ; 20403364 (ISSN) ; Ghasemi, F ; Golmohammadi, H ; Abbasi Moayed, S ; Nejad, M. A. F ; Fahimi-Kashani, N ; Jafarinejad, S ; Shahrajabian, M ; Hormozi-Nezhad, M. R ; Sharif University of Technology
Abstract
As in many other methods that have integrated nanoparticles (NPs), the chemical nose/tongue strategy has also progressed greatly since the entrance of NPs into this field. The fascinating tunable physicochemical properties of NPs have made them powerful candidates for array-based sensing platforms and have enabled the development of real-time, sensitive and portable systems that are able to target complex mixtures of analytes. In particular, the unique optical properties of NPs have a key role in providing promising array-based sensing approaches. This review will describe the main aspects and processes of most common NP-based optical sensor arrays. The fundamental steps in the design of a...
Electroosmotic flow and ionic conductance in a pH-regulated rectangular nanochannel
, Article Physics of Fluids ; Volume 29, Issue 6 , 2017 ; 10706631 (ISSN) ; Saidi, M. H ; Sadeghi, A ; Sharif University of Technology
Abstract
Infinite series solutions are obtained for electrical potential, electroosmotic velocity, ionic conductance, and surface physicochemical properties of long pH-regulated rectangular nanochannels of low surface potential utilizing the double finite Fourier transform method. Closed form expressions are also obtained for channels of large height to width ratio for which the depthwise variations vanish. Neglecting the Stern layer impact, the effects of EDL (Electric Double Layer) overlap, multiple ionic species, and association/dissociation reactions on the surface are all taken into account. Moreover, finite-element-based numerical simulations are conducted to account for the end effects as well...
Adsorption of terephthalic acid and p-toluic acid from aqueous solution using metal organic frameworks: Effect of molecular properties of the adsorbates and structural characteristics of the adsorbents
, Article Desalination and Water Treatment ; Volume 66 , 2017 , Pages 367-382 ; 19443994 (ISSN) ; Khorasheh, F ; Safekordi, A. A ; Sharif University of Technology
Desalination Publications
2017
Abstract
The adsorptive removal of terephthalic acid (TPA) and p-toluic acid (p-tol) by metal organic frameworks (MOF) of Cu-BTC, Fe-BTC, MIL-101(Cr) and MIL-53(Al) was investigated in this study. The influence of various factors including solution pH, contact time, and initial concentration of TPA and p-tol solutions on the adsorption behavior was evaluated. Different adsorption isotherms and kinetic models were used to fit experimental adsorption data. It was found that the Langmuir and Redlich-Peterson adsorption isotherms were adequate to represent the experimental data (R2 > 0.97) and that the adsorption kinetics was well-represented by a pseudo-second-order kinetic model (R2 > 0.98). The zeta...
Role of graphene surface ripples and thermal vibrations in molecular dynamics of C60
, Article Journal of Physical Chemistry C ; Volume 123, Issue 32 , 2019 , Pages 20026-20036 ; 19327447 (ISSN) ; Nejat Pishkenari, H ; Ejtehadi, M. R ; Akimov, A. V ; Sharif University of Technology
American Chemical Society
2019
Abstract
Nanocars are artificial molecular machines with chassis, axles, and wheels designed for nanoscale transport at materials' surfaces. Understanding the dependence of surface dynamics of nanocars on the substrate's physicochemical properties is critical to the design of the transport properties of such man-made nanoscale devices. Among the multitude of potential substrates for the nanotransporters, graphene exhibits intrinsic ripples on its surface, which may affect the surface dynamics of nanocars. In this work, we report our molecular dynamics study of motion of C60, a popular nanocar wheel, on the graphitic substrates with systematically controllable surface ripples. We find that surface...
Optical nanoprobes for chiral discrimination
, Article Analyst ; Volume 145, Issue 20 , 2020 , Pages 6416-6434 ; Ghasemi, F ; Fahimi Kashani, N ; Abbasi Moayed, S ; Orouji, A ; Jafar Nezhad Ivrigh, Z ; Shahdost Fard, F ; Hormozi Nezhad, M. R ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Chiral discrimination has always been a hot topic in chemical, food and pharmaceutical industries, especially when dealing with chiral drugs. Enantiomeric recognition not only leads to better understanding of the mechanism of molecular recognition in biological systems, but may further assist in developing useful molecular devices in biochemical and pharmaceutical studies. By emerging nanotechnology and exploiting nanomaterials in sensing applications, a great deal of attention has been given to the design of optical nanoprobes that are able to discriminate enantiomers of chiral analytes. This review explains how engineering nanoparticles (NPs) with desired physicochemical properties allows...
Deep eutectic solvents: Cutting-edge applications in cross-coupling reactions
, Article Green Chemistry ; Volume 22, Issue 12 , 2020 , Pages 3668-3692 ; Afshari, R ; Ramón, D. J ; Varma, R. S ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Deep eutectic solvents (DESs), surmised as "the organic reaction medium of the century", have reverberated a new symphony throughout the present green millennium. A brief historical account of the DES systems and their physicochemical properties as task-specific and designer solvents for cross-coupling reactions are appraised including the hole theory that explains the underlying mechanistic pathway for this emerging neoteric medium. The insights into cross-coupling reactions and their applications are included, highlighting the significant achievements pertaining to the dual role of DESs as a solvent and catalyst. In addition, popular "name-reactions"for the carbon-carbon and...
Silver and gold nanoparticles for antimicrobial purposes against multi-drug resistance bacteria
, Article Materials ; Volume 15, Issue 5 , 2022 ; 19961944 (ISSN) ; Ahmadi, S ; Akhavan, O ; Luque, R ; Sharif University of Technology
MDPI
2022
Abstract
Several pieces of research have been done on transition metal nanoparticles and their nanocomplexes as research on their physical and chemical properties and their relationship to biological features are of great importance. Among all their biological properties, the antibacterial and antimicrobial are especially important due to their high use for human needs. In this article, we will discuss the different synthesis and modification methods of silver (Ag) and gold (Au) nanoparticles and their physicochemical properties. We will also review some state-of-art studies and find the best relationship between the nanoparticles’ physicochemical properties and potential antimicrobial activity. The...
Core–Shell nanophotocatalysts: review of materials and applications
, Article ACS Applied Nano Materials ; Volume 5, Issue 1 , 2022 , Pages 55-86 ; 25740970 (ISSN) ; Rabiee, N ; Ahmadi, S ; Baneshi, M ; Khatami, M ; Iravani, S ; Varma, R. S ; Sharif University of Technology
American Chemical Society
2022
Abstract
Hybrid nanostructures and nanoarchitectures possess unique physicochemical properties such as high activity/functionality, enhanced physicochemical stability, and improved biocompatibility, which renders them suitable for various biomedical, pharmaceutical, environmental, and catalytic applications. In this context, core–shell nanophotocatalysts have shown superior activity compared to their counterparts, namely, their individual pristine semiconductors and composite materials components. Thus, the development of various innovative core–shell nanostructures as photocatalysts is of practical relevance in view of their unique properties with salient advantageous features applicable to, among...
A comprehensive review on planar boron nitride nanomaterials: From 2D nanosheets towards 0D quantum dots
, Article Progress in Materials Science ; Volume 124 , 2022 ; 00796425 (ISSN) ; Alem, S. A. A ; Hasanzadeh Azar, M ; Shayeganfar, F ; Manning, M. I ; Hatamie, A ; Pakdel, A ; Simchi, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Moving from two-dimensional hexagonal boron nitride (2D h-BN) flatlands towards their quantum sized zero-dimensional (0D) islands, as the newest member of the h-BN family, has recently opened up novel research areas due to the emergence of unique optical and physicochemical properties, excellent thermal and chemical stability, and desirable biocompatibility. This review elaborates on the fundamental properties of 2D and 0D h-BN nanomaterials and covers the latest progress in the fabrication and applications of BN nanosheets (BNNSs) and quantum dots (BNQDs). Initially, the transformation of properties in h-BN nanomaterials is discussed when moving from the 2D realm towards the 0D quantum...
Using nano-QSAR to determine the most responsible factor(s) in gold nanoparticle exocytosis
, Article RSC Advances ; Volume 5, Issue 70 , 2015 , Pages 57030-57037 ; 20462069 (ISSN) ; Hormozi Nezhad, M. R ; Parastar, H ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
There are, to date, few general answers to fundamental questions related to the interactions of nanoparticles (NPs) with living cells. Studies reported in the literature have delivered only limited principles about the nano-bio interface and thus the biological behavior of NPs is yet far from being completely understood. Combining computational tools with experimental approaches in this regard helps to precisely probe the nano-bio interface and allows the development of predictive and descriptive relationships between the structure and the activity of nanomaterials. In the present contribution, a nano-quantitative structure-activity relationship (nano-QSAR) model has been statistically...
A new functionalized magnetic nanocomposite of poly(methylacrylate) for the efficient removal of anionic dyes from aqueous media
, Article RSC Advances ; Volume 6, Issue 10 , 2016 , Pages 7982-7989 ; 20462069 (ISSN) ; Abedin Moghanaki, A ; Nasseri, S. A ; Sharif University of Technology
Royal Society of Chemistry
Abstract
A new magnetic nano-adsorbent was synthesized via the radical polymerization of methyl acrylate on modified Fe3O4 nanoparticles, followed by its functionalization by amidation of the methyl ester groups using pentaethylenehexamine, to create active adsorption sites for removing anionic dyes from aqueous media. Physicochemical properties of the adsorbent were then characterized by SEM, TEM, XRD, FTIR, TGA and CHN analysis. The prepared nanocomposite was used as adsorbent for the removal of anionic dyes, naphthol green B and chromeazurol S, from aqueous solution and assessed in view of the kinetics and isotherm adsorption, and the effect of solution pH, contact time and initial dye...
Geometry effect on electrokinetic flow and ionic conductance in pH-regulated nanochannels
, Article Physics of Fluids ; Volume 29, Issue 12 , 2017 ; 10706631 (ISSN) ; Saidi, M. H ; Moosavi, A ; Sadeghi, A ; Sharif University of Technology
Abstract
Semi-analytical solutions are obtained for the electrical potential, electroosmotic velocity, ionic conductance, and surface physicochemical properties associated with long pH-regulated nanochannels of arbitrary but constant cross-sectional area. The effects of electric double layer overlap, multiple ionic species, and surface association/dissociation reactions are all taken into account, assuming low surface potentials. The method of analysis includes series solutions which the pertinent coefficients are obtained by applying the wall boundary conditions using either of the least-squares or point matching techniques. Although the procedure is general enough to be applied to almost any...
Novel aspects of application of cadmium telluride quantum dots nanostructures in radiation oncology
, Article Applied Physics A: Materials Science and Processing ; Volume 123, Issue 8 , 2017 ; 09478396 (ISSN) ; Zare, H ; Karimi, S ; Rahighi, R ; Feizi, S ; Sharif University of Technology
Springer Verlag
2017
Abstract
In the last two decades, quantum dots nanomaterials have garnered a great deal of scientific interest because of their unique properties. Quantum dots (QDs) are inorganic fluorescent nanocrystals in the size range between 1 and 20 nm. Due to their structural properties, they possess distinctive properties and behave in different way from crystals in macro scale, in many branches of human life. Cadmium telluride quantum dots (CdTe QDs) were labeled with 68Ga radio nuclide for fast in vivo targeting and coincidence imaging of tumors. Using instant paper chromatography, the physicochemical properties of the Cadmium telluride quantum dots labeled with 68Ga NPs (68Ga@ CdTe QDs) were found high...
Molecular interaction between three-dimensional graphene aerogel and enzyme solution: effect on enzyme structure and function
, Article Journal of Molecular Liquids ; Volume 265 , 2018 , Pages 565-571 ; 01677322 (ISSN) ; Bagheri, Z ; Eskandari, F ; Ahadian, M. M ; Sharif University of Technology
Abstract
New membrane materials and processes have been extensively developed due to urgent needs for much more economic separation processes. Recently, graphene has been confirmed to be an excellent separation membrane. As there is no support in the obtained three-dimensional (3D) architecture constructed from tubular graphene network, it is possible to take full advantage of the large surface of graphene. In this study 3D graphene aerogels were synthesized by a simple method and modified to adjust hydrophilicity of the samples to achieve high liquid volumetric rate. Modified samples were used for the filtration of the enzymes including amylase, cellulase, lipase and protease. Slightly differently...