Loading...
Search for:
biological-applications
0.003 seconds
sp 2/sp 3 bonding ratio dependence of the band-gap in graphene oxide
, Article European Physical Journal B ; Volume 92, Issue 4 , 2019 ; 14346028 (ISSN) ; Akbari, I ; Ebrahimi, M. R ; Sharif University of Technology
Springer Heidelberg
2019
Abstract
Abstract: Although the band-gap in pure graphene is zero, the oxygenated graphene could have a considerable band-gap. The D/G peak intensity ratio is known as a measure of the size of sp3∕sp2 domains in graphene oxide (GO) sheets and determines the band-gap in GO sheets. Characterization results showed that the photoluminescence (PL) spectra of GO suspensions has a peak at ~604 nm and also the I(D)/I(G) intensity ratio of GO suspensions is 1.73. After reduction, a redshift appeared at PL spectrum (at 650 nm) and the I(D)/I(G) intensity ratio decrease to 1.26. Our results showed that the band-gap in GO is related to the I(D)/I(G) intensity ratio of GO suspensions and offers a mechanism for...
Personalized disease-specific protein corona influences the therapeutic impact of graphene oxide
, Article Nanoscale ; Volume 7, Issue 19 , Apr , 2015 , Pages 8978-8994 ; 20403364 (ISSN) ; Raheb, J ; Akhavan, O ; Arjmand, S ; Mashinchian, O ; Rahman, M ; Abdolahad, M ; Serpooshan, V ; Laurent, S ; Mahmoudi, M ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
The hard corona, the protein shell that is strongly attached to the surface of nano-objects in biological fluids, is recognized as the first layer that interacts with biological objects (e.g., cells and tissues). The decoration of the hard corona (i.e., the type, amount, and conformation of the attached proteins) can define the biological fate of the nanomaterial. Recent developments have revealed that corona decoration strongly depends on the type of disease in human patients from which the plasma is obtained as a protein source for corona formation (referred to as the 'personalized protein corona'). In this study, we demonstrate that graphene oxide (GO) sheets can trigger different...
A simple shape-controlled synthesis of gold nanoparticles using nonionic surfactants
, Article RSC Advances ; Volume 3, Issue 21 , 2013 , Pages 7726-7732 ; 20462069 (ISSN) ; Karami, P ; Robatjazi, H ; Sharif University of Technology
2013
Abstract
Green and simple synthesis strategies have gained tremendous popularity for the production of anisotropically-shaped noble metallic nanoparticles. The long-term stability of the produced particles, the short timescale of the target reaction(s), as well as the use of non-toxic chemicals, are pivotal features of a useful green procedure. Herein we describe a simple and convenient wet-chemical approach to synthesize stable, non-toxic and water-soluble small gold nanotriangles (GNTs) and gold nanospheres (GNSs) in one step at room temperature, using Tween 20 and Tween 80, respectively. A high level of purity and monodispersity was obtained for the GNTs, in addition to an excellent colloidal...
Thermal transport characteristics of non-newtonian electroosmotic flow in a slit microchannel
, Article ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2011, 19 June 2011 through 22 June 2011 ; Volume 1 , June , 2011 , Pages 169-176 ; 9780791844632 (ISBN) ; Sadeghi, A ; Saidi, M. H ; Sharif University of Technology
2011
Abstract
Electroosmosis has many applications in fluid delivery at microscale, sample collection, detection, mixing and separation of various biological and chemical species. In biological applications, most fluids are known to be non-Newtonian. Therefore, the study of thermal features of non-Newtonian electroosmotic flow is of great importance for scientific communities. In the present work, the fully developed electroosmotic flow of power-law fluids in a slit microchannel is investigated. The related equations are transformed into non-dimensional forms and necessary changes are made to adapt them for non-Newtonian fluids of power-law model. Results show that depending on different flow parameters...
Utilization of gene expression programming for modeling of mechanical performance of titanium/carbonated hydroxyapatite nanobiocomposites: The combination of artificial intelligence and material science
, Article International Journal of Engineering, Transactions A: Basics ; Volume 34, Issue 4 , 2021 , Pages 948-955 ; 17281431 (ISSN) ; Khayati, G. R ; Hasani, A ; Sharif University of Technology
Materials and Energy Research Center
2021
Abstract
Titanium carbonated hydroxyapatite (Ti/CHA) nanobiocomposites have extensive biological applications due to the excellent biocompatibility and similar characteristics to the human bone. Ti/CHA nanobiocomposite has good biological properties but it suffer from diverse characteristics especially in hardness, Young's modulus, apparent porosity and relative density. This investigation is an attempt to propose the predictive models using gene expression programming (GEP) to estimate these characteristics. In this regards, GEP is used to model and compare the effect of practical variables including pressure, Ti/CHA contents and sintering temperature on their monitored properties. To achieve this...
Development of sol-gel-derived multi-wall carbon nanotube/hydroxyapatite nanocomposite powders for bone substitution
, Article Journal of Composite Materials ; Vol. 48, issue. 4 , February , 2014 , pp. 483-489 ; ISSN: 00219983 ; Abrishamchian, A ; Najafi, F ; Mohammadi, M ; Najafi, H ; Tahriri, M ; Sharif University of Technology
Abstract
Carbon nanotubes with unique physical and mechanical properties have shown great potential for biological applications, including tissue engineering and mimicking the structure and properties of human bones. In the present work, sol-gel synthesized nanocomposite powder of multi-wall carbon nanotube/hydroxyapatite characterized using field-emission scanning electron microscopy, transmission electron microscope, X-ray diffraction, Fourier transform infra-red spectroscopy and thermal analyses. The results show homogenous dispersion of nanotube in well-crystallized hydroxyapatite ceramic matrix. Scanning electron microscopy and transmission electron microscope observations show the sodium...
Facile fabrication and characterization of amino-functionalized Fe 3O4 cluster@SiO2 core/shell nanocomposite spheres
, Article Materials Research Bulletin ; Volume 48, Issue 6 , 2013 , Pages 2023-2028 ; 00255408 (ISSN) ; Kazemeini, M ; Arpanaei, A ; Sharif University of Technology
2013
Abstract
We developed a modified straightforward method for the fabrication of uniformly sized silica-coated magnetite clusters core/shell type nanocomposite particles. Proposed simple one-step processing method permits quick production of materials in high yield. The structural, surface, and magnetic characteristics of the nanocomposite particles were investigated by transmission electron microscopy (TEM), scanning electron microscope (SEM), powder X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and Fourier-transform infrared (FTIR). The sphere-shaped particles almost have the average diameter of 120 nm, with a magnetic cluster core of 80 ± 15 nm, and a silica shell of 25 ± 10 nm...
On the motion of Newtonian and non-Newtonian liquid drops
, Article Scientia Iranica ; Volume 19, Issue 5 , 2012 , Pages 1265-1278 ; 10263098 (ISSN) ; Maleki, A ; Firoozabadi, B ; Afshin, H ; Sharif University of Technology
2012
Abstract
In the present study, the motion of Newtonian and non-Newtonian liquid drops has been investigated experimentally. In order to investigate the effect of bulk fluid on drops, we have used water and air, as two fluids with different properties, and various industrial and biological applications. Image processing is utilized to analyze the images obtained by a high speed camera. The research has been separated into two parts. The first part has been devoted to the experiments in which air is the bulk fluid, and the second is related to the experiment carried out in water. The range of Reynolds number is, approximately, 50
Nanofibrous hydrogel with stable electrical conductivity for biological applications
, Article Polymer (United Kingdom) ; Volume 97 , 2016 , Pages 205-216 ; 00323861 (ISSN) ; Rezayat, S. M ; Vashegani Farahani, E ; Mahmoudifard, M ; Zamanlui, S ; Soleimani, M ; Sharif University of Technology
Elsevier Ltd
Abstract
3D hydrogel environment with both unique properties of nanofibrous structure and electrical character can provide a promising scaffold for skeletal muscle tissue engineering approaches. Herein, the poly acrylic acid (PAA)-based hydrogel was engineered to conductive one by aniline polymerization in the form of nanofibers. The poly aniline (PANi) nanofibers were made by the optimized chemical reactions between the surface carboxylate groups of based hydrogel and protonated aniline monomers. We found that the strong bonding which was created between PANi and camphor sulphonic acid (CSA) as a doping agent supporting the stable electrical property of composite hydrogel after incubation in cell...
Investigation of a Novel Microfluidic Device for Label-Free Ferrohydrodynamic Cell Separation on a Rotating Disk
, Article IEEE Transactions on Biomedical Engineering ; Volume 67, Issue 2 , 2020 , Pages 372-378 ; Besanjideh, M ; Sharif University of Technology
IEEE Computer Society
2020
Abstract
Negative magnetophoresis is a novel and attractive method for continuous microparticle sorting inside a magnetic medium. In this method, diamagnetic particles are sorted based on their sizes using magnetic buoyancy force and without any labeling process. Although this method provides some attractive features, such as low-cost fabrication and ease of operation, there are some obstacles that adversely affect its performance, especially for biological applications. Most types of magnetic media, such as ferrofluids, are not biocompatible, and the time-consuming process of sample preparation can be threatening to the viability of the cells within the sample. Furthermore, in this method, both the...
Synthesis of magnetic ions-doped QDs Synthesized Via a facial aqueous solution method for Optical/MR dual-modality imaging applications
, Article Journal of Fluorescence ; Volume 31, Issue 3 , 2021 , Pages 897-906 ; 10530509 (ISSN) ; Zare, H ; Shahedi, Z ; Fazaeli, Y ; Rahighi, R ; Sharif University of Technology
Springer
2021
Abstract
This research reports the preparation and examination of Cadmium Telluride (CdTe) Quantum Dots and doping CdTe QDs with Europium (Eu), Gadolinium (Gd), and Manganese (Mn) prepared in aqueous solution using TGA as a capping agent. Magnetic QDs (MQDs) are important agents for fluorescence (FL) /magnetic resonance (MR) dual-modal imaging due to their excellent optical and magnetic properties. Herein, the chemical bonds, structural, fluorescence, and magnetized properties of CdTe QDs and effect of Mn, Eu, and Gd ions doping on their properties were examined by X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTM), Energy-dispersive X-ray spectroscopy (EDX),...
In-vitro evaluation of thermoplastic starch/ beta-tricalcium phosphate nano-biocomposite in bone tissue engineering
, Article Ceramics International ; Volume 47, Issue 11 , 2021 , Pages 15458-15463 ; 02728842 (ISSN) ; Bagheri, R ; Taherimehr, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Thermoplastic starch (TPS), as a natural based polymer, is known to have the capability to be used in biological applications due to its biocompatibility and biodegradability. In this study, mechanical properties of TPS are enhanced by incorporating bioactive β-tricalcium phosphate (β-TCP) particles for bone tissue engineering applications. Starch-based nanocomposites containing 3, 5, and 10 wt% of β-TCP nanoparticles (TT3, TT5, TT10) were made using a co-rotating twin-screw extruder. Dynamic light scattering (DLS) and X-ray diffraction (XRD) techniques were employed to analyze the nanocomposites. Moreover, degradability, swelling degree, and biomineralization in a simulated body fluid (SBF)...