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Smart micro/nanoparticles in stimulus-responsive drug/gene delivery systems
, Article Chemical Society Reviews ; Volume 45, Issue 5 , 2016 , Pages 1457-1501 ; 03060012 (ISSN) ; Ghasemi, A ; Sahandi Zangabad, P ; Rahighi, R ; Moosavi Basri, S. M ; Mirshekari, H ; Amiri, M ; Shafaei Pishabad, Z ; Aslani, A ; Bozorgomid, M ; Ghosh, D ; Beyzavi, A ; Vaseghi, A ; Aref, A. R ; Haghani, L ; Bahrami, S ; Hamblin, M. R ; Sharif University of Technology
Royal Society of Chemistry
2016
Abstract
New achievements in the realm of nanoscience and innovative techniques of nanomedicine have moved micro/nanoparticles (MNPs) to the point of becoming actually useful for practical applications in the near future. Various differences between the extracellular and intracellular environments of cancerous and normal cells and the particular characteristics of tumors such as physicochemical properties, neovasculature, elasticity, surface electrical charge, and pH have motivated the design and fabrication of inventive "smart" MNPs for stimulus-responsive controlled drug release. These novel MNPs can be tailored to be responsive to pH variations, redox potential, enzymatic activation, thermal...
Sensitive determination of dopamine in the presence of uric acid and ascorbic acid using TiO2 nanotubes modified with Pd, Pt and Au nanoparticles
, Article Analyst ; Volume 136, Issue 11 , 2011 , Pages 2322-2329 ; 00032654 (ISSN) ; Li, C ; Mahshid, S. S ; Askari, M ; Dolati, A ; Yang, L ; Luo, S ; Cai, Q ; Sharif University of Technology
2011
Abstract
A simple modified TiO2 nanotubes electrode was fabricated by electrodeposition of Pd, Pt and Au nanoparticles. The TiO2 nanotubes electrode was prepared using the anodizing method, followed by modifying Pd nanoparticles onto the tubes surface, offering a uniform conductive surface for electrodeposition of Pt and Au. The performance of the modified electrode was characterized by cyclic voltammetry and differential pulse voltammetry methods. The Au/Pt/Pd/TiO2 NTs modified electrode represented a high sensitivity towards individual detection of dopamine as well as simultaneous detection of dopamine and uric acid using 0.1 M phosphate buffer solution (pH 7.00) as the base solution. In both case,...
Useful multivariate kinetic analysis: Size determination based on cystein-induced aggregation of gold nanoparticles
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 115 , 2013 , Pages 588-594 ; 13861425 (ISSN) ; Nezhad, M. R. H ; Abdollahi, H ; Sharif University of Technology
2013
Abstract
This study describes spectrometric monitored kinetic processes to determine the size of citrate-capped Au nanoparticles (Au NPs) based on aggregation induced by L-cysteine (L-Cys) as a molecular linker. The Au NPs association process is thoroughly dependent on pH, concentration and size of nanoparticles. Size dependency of aggregation inspirits to determine the average diameters of Au NPs. For this aim the procedure is achieved in aqueous medium at pH 7 (phosphate buffer), and multivariate data including kinetic spectra of Au NPs are collected during aggregation process. Subsequently partial least squares (PLS) modeling is carried out analyzing the obtained data. The model is built on the...
Interactions of coinage metal clusters with histidine and their effects on histidine acidity; Theoretical investigation
, Article Organic and Biomolecular Chemistry ; Volume 10, Issue 47 , Oct , 2012 , Pages 9373-9382 ; 14770520 (ISSN) ; Jamshidi, Z ; Tehrani, Z. A ; Fattahi, A ; Sharif University of Technology
2012
Abstract
Understanding the nature of interaction between metal nanoparticles and biomolecules such as amino acids is important in the development and design of biosensors. In this paper, binding of M3 clusters (M = Au, Ag and Cu) with neutral and anionic forms of histidine amino acid was studied using density functional theory (DFT-B3LYP). It was found that the interaction of histidine with M3 clusters is governed by two major bonding factors: (a) the anchoring N-M and O-M bonds and (b) the nonconventional N-H⋯M and O-H⋯M hydrogen bonds. The nature of these chemical bonds has been investigated based on quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) analyses. In the next...
Effect of hydrogen bonds on pK a values: Importance of networking
, Article Journal of the American Chemical Society ; Volume 134, Issue 25 , 2012 , Pages 10646-10650 ; 00027863 (ISSN) ; Abedin, A ; Fattahi, A ; Kass, S. R ; Sharif University of Technology
2012
Abstract
The pK a of an acyclic aliphatic heptaol ((HOCH 2CH 2CH(OH)CH 2) 3COH) was measured in DMSO, and its gas-phase acidity is reported as well. This tertiary alcohol was found to be 10 21 times more acidic than tert-butyl alcohol in DMSO and an order of magnitude more acidic than acetic acid (i.e., pK a = 11.4 vs 12.3). This can be attributed to a 21.9 kcal mol -1 stabilization of the charged oxygen center in the conjugate base by three hydrogen bonds and another 6.3 kcal mol -1 stabilization resulting from an additional three hydrogen bonds between the uncharged primary and secondary hydroxyl groups. Charge delocalization by both the first and second solvation shells may be used to facilitate...
Application of silver nanoparticles and principal component-artificial neural network models for simultaneous determination of levodopa and benserazide hydrochloride by a kinetic spectrophotometric method
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 82, Issue 1 , November , 2011 , Pages 25-30 ; 13861425 (ISSN) ; Hormozi Nezhad, M. R ; Khodaveisi, J ; Sharif University of Technology
2011
Abstract
A multicomponent analysis method based on principal component analysis-artificial neural network model (PC-ANN) is proposed for the simultaneous determination of levodopa (LD) and benserazide hydrochloride (BH). The method is based on the reaction of levodopa and benserazide hydrochloride with silver nitrate as an oxidizing agent in the presence of PVP and formation of silver nanoparticles. The reaction monitored at analytical wavelength 440 nm related to surface plasmon resonance band of silver nanoparticles. Differences in the kinetic behavior of the levodopa and benserazide hydrochloride were exploited by using principal component analysis, an artificial neural network (PC-ANN) to resolve...
UV-prepared salep-based nanoporous hydrogel for controlled release of tetracycline hydrochloride in colon
, Article Journal of Photochemistry and Photobiology B: Biology ; Volume 102, Issue 3 , March , 2011 , Pages 232-240 ; 10111344 (ISSN) ; Pourjavadi, A ; Ghavami, S ; Soleyman, R ; Jafarpour, F ; Sharif University of Technology
2011
Abstract
A highly swelling nanoporous hydrogel (NPH) was synthesized via UV-irradiation graft copolymerization of acrylic acid (AA) onto salep backbone and its application as a carrier matrix for colonic delivery of tetracycline hydrochloride (TH) was investigated. Optimized synthesis of the hydrogel was performed by the classic method. The swelling behavior of optimum hydrogel was measured in different media. The hydrogel formation was confirmed by Fourier transform infrared spectroscopy (FTIR) and thermo-gravimetric analysis (TGA/DTG/DTA). The study of the surface morphology of hydrogels using SEM showed a nanoporous (average pore size: about 350 nm) structure for the sample obtained under...
Voltammetric studies of Azathioprine on the surface of graphite electrode modified with graphene nanosheets decorated with Ag nanoparticles
, Article Materials Science and Engineering C ; Volume 58 , 2016 , Pages 1098-1104 ; 09284931 (ISSN) ; Iraji Zad, A ; Shahrokhian, S ; Sharif University of Technology
Elsevier Ltd
Abstract
By using graphene nanosheets decorated with Ag nanoparticles (AgNPs-G) as an effective approach for the surface modification of pyrolytic graphite electrode (PGE), a sensing platform was fabricated for the sensitive voltammetric determination of Azathioprine (Aza). The prepared AgNPs-G nanosheets were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-vis and Raman spectroscopy techniques. The electrochemical behavior of Aza was investigated by means of cyclic voltammetry. Comparing to the bare PGE, a remarkable enhancement was observed in the response characteristics of Aza on the surface of the modified electrode (AgNPs-G/PGE) as well as a noticeable...
ThThnated Development of a pH assisted AgNP-based colorimetric sensor Array for simultaneous identification of phosalone and azinphosmethyl pesticides
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 219 , 2019 , Pages 496-503 ; 13861425 (ISSN) ; Abbasi Moayed, S ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Development of simple and rapid methods for identification of pesticides, due to their broad usage and harmful effects on mammals, has been known as a critical demand. Herein, we have introduced a silver nanoparticle (AgNP)based colorimetric sensor array for simultaneous identification of Azinphosmethyl (AM)and Phosalone (PS)pesticides. In the presence of the target pesticides, unmodified AgNPs at various pHs (4.5, 5.5 and 9.5)showed different aggregation behaviors. As a result of aggregation, the color and UV–Vis spectra of AgNPs changed differentially, leading to distinct response patterns for AM and PS. The aggregation induced spectral changes of AgNPs, were used to identify AM and PS...
Model-based analysis for kinetic complexation study of Pizda and Cu(II)
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 70, Issue 3 , August , 2008 , Pages 674-681 ; 13861425 (ISSN) ; Maeder, M ; Jalali Heravi, M ; Norman, S. E ; Sharif University of Technology
2008
Abstract
In the present work, the multivariate kinetic complexation of a new synthesized ligand, 1-(2″-hydroxyl cyclohexyl)-3′-[aminopropyl]-4-[3′-aminopropyl]piperazine (Pizda) and Cu2+ in 50% ethanol-water solution is investigated using the UV-vis stopped-flow technique and state-of-the-art multi-wavelength numerical analysis. Model-based least squares fitting analysis or hard modeling is a specific part of chemometrics which is based on mathematical relationships for describing the measurements. Some recent developments include the incorporation of the effects of non-ideal experimental conditions into the fitting algorithm so it can substantially simplify experimental procedures. In this study no...
Optical detection of phenolic compounds based on the surface plasmon resonance band of Au nanoparticles
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 71, Issue 1 , 2008 , Pages 199-203 ; 13861425 (ISSN) ; Alimohammadi, M ; Tashkhourian, J ; Razavian, S. M ; Sharif University of Technology
2008
Abstract
An indirect colorimetric method is presented for detection of trace amounts of hydroquinone (1), catechol (2) and pyrogallol (3). The reduction of AuCl4- to Gold nanoparticles (Au-NPs) by these phenolic compounds in the presence of cetyltrimethylammonium chloride (CTAC) produced very intense surface plasmon resonance peak of Au-NPs. The plasmon absorbance of Au-NPs allows the quantitative colorimetric detection of the phenolic compounds. The calibration curves derived from the changes in absorbance at λ = 568 nm were linear with concentration of hydroquinone, catechol and pyrogallol in the range of 7.0 × 10-7 to 1.0 × 10-4M, 6.0 × 10-6 to 2.0 × 10-4 M and 6.0 × 10-7 to 1.0 × 10-4 M,...
Determination of fentanyl in human plasma by head-space solid-phase microextraction and gas chromatography-mass spectrometry
, Article Journal of Pharmaceutical and Biomedical Analysis ; Volume 43, Issue 5 , 2007 , Pages 1763-1768 ; 07317085 (ISSN) ; Es-haghi, A ; Khalilian, F ; Rouini, M. R ; Sharif University of Technology
2007
Abstract
A head-space solid-phase microextraction (HS-SPME) method coupled to GC-MS was developed to extract fentanyl from human plasma. The protein binding was reduced by acidification and, eventually, the sample was deproteinized with trichloroacetic acid. The parameters influencing adsorption (extraction time, temperature, pH and salt addition) and desorption (desorption time and temperature) of the analyte on the fibre were investigated and validated for method development. The developed method proved to be rapid, simple, easy and inexpensive and offers high sensitivity and reproducibility. Linear range was obtained from 0.1 ng/ml to 2 μg/ml. The limit of detection was 0.03 ng/ml while an...
Miniaturized salting-out liquid-liquid extraction in a coupled-syringe system combined with HPLC-UV for extraction and determination of sulfanilamide
, Article Talanta ; Vol. 121 , April , 2014 , pp. 199-204 ; ISSN: 00399140 ; Khosraviani, M ; Sadegh Amini-Fazl, M ; Sharif University of Technology
Abstract
In salting-out liquid-liquid extraction (SALLE) technique, water-miscible organic solvents are used for extraction of polar analytes from saline solutions. In this study, for the first time, a coupled 1-mL syringes system was utilized to perform a miniaturized SALLE method. Sulfanilamide antibiotic was extracted and determined via the developed method followed by high performance liquid chromatography-ultraviolet detection (HPLC-UV). The extraction process was carried out by rapid shooting of acetonitrile as extraction solvent (syringe B) into saline aqueous sample solution (syringe A), and then the shooting was repeated several times at a rate of 1 cycle s-1. Thereby, an extremely large...
Temperature: the "ignored" factor at the nanobio interface
, Article ACS Nano ; Volume 7, Issue 8 , 2013 , Pages 6555-6562 ; 19360851 (ISSN) ; Abdelmonem, A. M ; Behzadi, S ; Clement, J. H ; Dutz, S ; Ejtehadi, M. R ; Hartmann, R ; Kantner, K ; Linne, U ; Maffre, P ; Metzler, S ; Moghadam, M. K ; Pfeiffer, C ; Rezaei, M ; Ruiz-Lozano, P ; Serpooshan, V ; Shokrgozar, M. A ; Nienhaus, G. U ; Parak, W. J ; Sharif University of Technology
2013
Abstract
Upon incorporation of nanoparticles (NPs) into the body, they are exposed to biological fluids, and their interaction with the dissolved biomolecules leads to the formation of the so-called protein corona on the surface of the NPs. The composition of the corona plays a crucial role in the biological fate of the NPs. While the effects of various physicochemical parameters on the composition of the corona have been explored in depth, the role of temperature upon its formation has received much less attention. In this work, we have probed the effect of temperature on the protein composition on the surface of a set of NPs with various surface chemistries and electric charges. Our results...
Removal of toxic heavy metal ions from waste water by functionalized magnetic core-zeolitic shell nanocomposites as adsorbents
, Article Environmental Science and Pollution Research ; Volume 20, Issue 6 , 2013 , Pages 3900-3909 ; 09441344 (ISSN) ; Gholami, M. R ; Sharif University of Technology
2013
Abstract
Functionalized magnetic core-zeolitic shell nanocomposites were prepared via hydrothermal and precipitation methods. The products were characterized by vibrating sample magnetometer, X-ray powder diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption-desorption isotherms, and transmission electron microscopy analysis. The growth of mordenite nanocrystals on the outer surface of silica-coated magnetic nanoparticles at the presence of organic templates was well approved. The removal performance and the selectivity of mixed metal ions (Pb2+ and Cd2+) in aqueous solution were investigated via the sorption process. The batch method was employed to study the sorption kinetic,...
The effect of poly(ethylene glycol) coating on colloidal stability of superparamagnetic iron oxide nanoparticles as potential MRI contrast agent
, Article International Journal of Pharmaceutics ; Volume 433, Issue 1-2 , 2012 , Pages 129-141 ; 03785173 (ISSN) ; Madaah Hosseini, H. R ; Shokrgozar, M. A ; Ahmadi, R ; Oghabian, M. A ; Sharif University of Technology
2012
Abstract
Superparamganetic iron oxide-based contrast agents in magnetic resonance imaging (MRI) have offered new possibility for early detection of lymph nodes and their metastases. According to important role of nanoparticle size in biodistribution, magnetite nanoparticles coated with different polyethylene glycol (PEG) concentrations up to 10/1 PEG/iron oxide weight ratio in an ex situ manner. To predict the PEG-coated nanoparticle behavior in biological media, such as blood stream or tissue, colloidal stability evaluation was performed to estimate the coating endurance in different conditions. Accordingly, optical absorbance measurements were conducted in solutions with different values of pH and...
Removal of chlorophenolic derivatives by soil isolated ascomycete of Paraconiothyrium variabile and studying the role of its extracellular laccase
, Article Journal of Hazardous Materials ; Volume 209-210 , 2012 , Pages 199-203 ; 03043894 (ISSN) ; Movahednia, M. M ; Yaghmaei, S ; Tabatabaei Sameni, M ; Rastegar, H ; Sadighi, A ; Faramarzi, M. A ; Sharif University of Technology
2012
Abstract
The ability of Paraconiothyrium variabile, a laccase producing ascomycete recently isolated from soil, was studied to eliminate chlorophenol derivatives in submerged culture medium. Among the tested compounds, ρ-chlorophenol (ρ-CP) and pentachlorophenol (PCP) were found to have minimum and maximum toxic effects, respectively, on the growth of the microorganism and at the same time high and low bioelimination percentages. The fungal strain was able to remove 86% of ρ-CP (with initial concentration of 40mgl -1) and 56% of 2,4-dichlorophenol (2,4-DCP; with same concentration as ρ-CP) after 9 days of incubation while no elimination was observed in the presence of 2,4,6-trichlorophenol...
Bioleaching of tungsten-rich spent hydrocracking catalyst using Penicillium simplicissimum
, Article Bioresource Technology ; Volume 102, Issue 2 , January , 2011 , Pages 1567-1573 ; 09608524 (ISSN) ; Yaghmaei, S ; Mousavi, S. M ; Sharif University of Technology
2011
Abstract
Adaptation of Penicillium simplicissimum with different heavy metals present in a spent hydrocracking catalyst, as well as one-step, two-step, and spent medium bioleaching of the spent catalyst by the adapted fungus, was examined in batch cultures. Adaptation experiments with the single metal ions Ni, Mo, Fe, and W showed that the fungus could tolerate up to 1500. mg/L Ni, 8000. mg/L Mo, 3000. mg/L Fe, and 8000. mg/L W. In the presence of multi-metals, the fungus was able to tolerate up to 300. mg/L Ni, 200. mg/L Mo, 150. mg/L Fe and 2500. mg/L W. A total of 3% (w/v) spent catalyst generally gave the maximum extraction yields in the two-step bioleaching process (100% of W, 100% of Fe, 92.7%...
Extraction of fluoxetine from aquatic and urine samples using sodium dodecyl sulfate-coated iron oxide magnetic nanoparticles followed by spectrofluorimetric determination
, Article Analytica Chimica Acta ; Volume 692, Issue 1-2 , 2011 , Pages 80-84 ; 00032670 (ISSN) ; Zandi, O ; Aghakhani, A ; Sharif University of Technology
Abstract
A new method based on the combination of magnetic solid phase extraction (MSPE) and spectrofluorimetric determination was developed for isolation and preconcentration of fluoxetine form aquatic and biological samples using sodium dodecyl sulfate (SDS) coated Fe3O4 nanoparticles (NPs) as a sorbent. The unique properties of Fe3O4 NPs including high surface area and strong magnetism were utilized effectively in the MSPE process. Effect of different parameters influencing the extraction efficiency of fluoxetine including the amount of Fe3O4 and SDS, pH value, sample volume, extraction time, desorption solvent and time were optimized. Under optimized condition, the method was successfully applied...
Application of chitosan-citric acid nanoparticles for removal of chromium (VI)
, Article International Journal of Biological Macromolecules ; Volume 80 , September , 2015 , Pages 431-444 ; 01418130 (ISSN) ; Younesi, H ; Hajati, S ; Borghei, S. M ; Sharif University of Technology
Elsevier
2015
Abstract
In the present study, CS-CA nanoparticle was prepared for forming a new amide linkage, by grafting the amino groups of CS in the presence of carboxylic groups of CA that acts as cross-linking agent. The as-prepared CS-CA nanoparticle samples were characterized by use of dynamic light scattering (DLS), scanning electron microscopy (SEM), Fourier-transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques, which showed that the cross-linking agent preserved during the chemical modifications. The adsorption capacity of the CS-CA nanoparticles for the removal of Cr (VI) in aqueous solution was studied. The adsorption equilibrium data...