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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...
Multifunctional conductive biomaterials as promising platforms for cardiac tissue engineering
, Article ACS Biomaterials Science and Engineering ; Volume 7, Issue 1 , 2021 , Pages 55-82 ; 23739878 (ISSN) ; Vahdat, S ; Baheiraei, N ; Razavi, M ; Norahan, M. H ; Baharvand, H ; Sharif University of Technology
American Chemical Society
2021
Abstract
Adult cardiomyocytes are terminally differentiated cells that result in minimal intrinsic potential for the heart to self-regenerate. The introduction of novel approaches in cardiac tissue engineering aims to repair damages from cardiovascular diseases. Recently, conductive biomaterials such as carbon- and gold-based nanomaterials, conductive polymers, and ceramics that have outstanding electrical conductivity, acceptable mechanical properties, and promoted cell-cell signaling transduction have attracted attention for use in cardiac tissue engineering. Nevertheless, comprehensive classification of conductive biomaterials from the perspective of cardiac cell function is a subject for...
Fabrication and characterization of scaffolds containing different amounts of allantoin for skin tissue engineering
, Article Scientific Reports ; Volume 11, Issue 1 , 2021 ; 20452322 (ISSN) ; Shamloo, A ; Bahadoran, M ; Moravvej, H ; Sharif University of Technology
Nature Research
2021
Abstract
Using the skin tissue engineering approach is a way to help the body to recover its lost skin in cases that the spontaneous healing process is either impossible or inadequate, such as severe wounds or burns. In the present study, chitosan/gelatin-based scaffolds containing 0.25, 0.5, 0.75, and 1% allantoin were created to improve the wounds’ healing process. EDC and NHS were used to cross-link the samples, which were further freeze-dried. Different in-vitro methods were utilized to characterize the specimens, including SEM imaging, PBS absorption and degradation tests, mechanical experiments, allantoin release profile assessment, antibacterial assay, and cell viability and adhesion tests....
X-ray diffraction analysis and williamson-hall method in usdm model for estimating more accurate values of stress-strain of unit cell and super cells (2 × 2 × 2) of hydroxyapatite, confirmed by ultrasonic pulse-echo test
, Article Materials ; Volume 14, Issue 11 , 2021 ; 19961944 (ISSN) ; Palevicius, A ; Dashti, A ; Nasiri, S ; Monshi, A ; Doustmohammadi, A ; Vilkauskas, A ; Janusas, G ; Sharif University of Technology
MDPI AG
2021
Abstract
Taking into account X-ray diffraction, one of the well-known methods for calculating the stress-strain of crystals is Williamson-Hall (W–H). The W-H method has three models, namely (1) Uniform deformation model (UDM); (2) Uniform stress deformation model (USDM); and (3) Uniform deformation energy density model (UDEDM). The USDM and UDEDM models are directly related to the modulus of elasticity (E). Young’s modulus is a key parameter in engineering design and materials development. Young’s modulus is considered in USDM and UDEDM models, but in all previous studies, researchers used the average values of Young’s modulus or they calculated Young’s modulus only for a sharp peak of an XRD pattern...
Relationship between young’s modulus and planar density of unit cell, super cells (2 × 2 × 2), symmetry cells of perovskite (catio3) lattice
, Article Materials ; Volume 14, Issue 5 , 2021 , Pages 1-15 ; 19961944 (ISSN) ; Palevicius, A ; Nasiri, S ; Dashti, A ; Vilkauskas, A ; Janusas, G ; Sharif University of Technology
MDPI AG
2021
Abstract
Calcium titanate-CaTiO3 (perovskite) has been used in various industrial applications due to its dopant/doping mechanisms. Manipulation of defective grain boundaries in the structure of perovskite is essential to maximize mechanical properties and stability; therefore, the structure of perovskite has attracted attention, because without fully understanding the perovskite structure and diffracted planes, dopant/doping mechanisms cannot be understood. In this study, the areas and locations of atoms and diffracted planes were designed and investigated. In this research, the relationship between Young’s modulus and planar density of unit cell, super cells (2 × 2 × 2) and symmetry cells of nano...
Nanofibrillated chitosan coated highly ordered titania nanotubes array/graphene nanocomposite with improved biological characters
, Article Carbohydrate Polymers ; Volume 254 , 2021 ; 01448617 (ISSN) ; Bagheri, R ; Heidarpour, H ; Vossoughi, M ; Golizadeh, M ; Samadikuchaksaraei, A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Designing multifunctional surfaces is key to develop advanced materials for orthopedic applications. In this study, we design a double-layer coating, assembled onto the completely regular titania nanotubes (cRTNT) array. Benefiting from the biological and topological characteristics of chitosan nanofibers (CH) and reduced graphene oxide (RGO) through a unique assembly, the designed material features promoted osteoblast cell viability, prolonged antibiotic release profile, as well as inhibited bacterial biofilm formation. The synergistic effect of RGO and CH on the biological performance of the surface is investigatSed. The unique morphology of the nanofibers leads to the partial coverage of...
Application of exact continuum size-dependent theory for stability and frequency analysis of a curved cantilevered microtubule by considering viscoelastic properties
, Article Engineering with Computers ; Volume 37, Issue 4 , 2021 , Pages 3629-3648 ; 01770667 (ISSN) ; Habibi, M ; Tounsi, A ; Safarpour, H ; Safa, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
The stability analysis of cantilevered curved microtubules in axons regarding various size elements and using the generalized differential quadrature method for solving equations is reported. The impacts of covering MAP Tau proteins along with cytoplasm are taken into account as the elastic medium. Curved cylindrical nanoshell considering thick wall is used to model the microtubules. The factor of length scale (l/R = 0.2) used in modified couple stress theory would result in more accuracy when it comes to comparison with experiments, while alternative theories presented in this paper provide less precise outcomes. Due to the reported precise results, at the lower value of the time-dependent...
Biomimetic ultraflexible piezoresistive flow sensor based on graphene nanosheets and PVA hydrogel
, Article Advanced Materials Technologies ; 2021 ; 2365709X (ISSN) ; Moradi, H ; Wu, S ; Han, Z. J ; Razmjou, A ; Asadnia, M ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Flow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze-like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting...
Computational study of geometric effects of bottom wall microgrooves on cell docking inside microfluidic devices
, Article Journal of Mechanics in Medicine and Biology ; Volume 21, Issue 2 , 2021 ; 02195194 (ISSN) ; Saadatmand, M ; Sharif University of Technology
World Scientific
2021
Abstract
Cells docking inside microfluidic devices is effective in studying cell biology, cell-based biosensing, as well as drug screening. Furthermore, single cell and regularly cells docking inside the microstructure of microfluidic systems are advantageous in different analyses of single cells exposed to equal drug concentration and mechanical stimulus. In this study, we investigated bottom wall microgrooves with semicircular and rectangular geometries with different sizes which are suitable for single cell docking along the length of the microgroove in x-direction and numerous cells docking regularly in one line inside the microgroove in a 3D microchannel. We used computational fluid dynamics to...
Development of ultrasensitive biomimetic auditory hair cells based on piezoresistive hydrogel nanocomposites
, Article ACS Applied Materials and Interfaces ; Volume 13, Issue 37 , 2021 , Pages 44904-44915 ; 19448244 (ISSN) ; Moradi, H ; Pastras, C. J ; Abolpour Moshizi, S ; Wu, S ; Asadnia, M ; Sharif University of Technology
American Chemical Society
2021
Abstract
With an ageing population, hearing disorders are predicted to rise considerably in the following decades. Thus, developing a new class of artificial auditory system has been highlighted as one of the most exciting research topics for biomedical applications. Herein, a design of a biocompatible piezoresistive-based artificial hair cell sensor is presented consisting of a highly flexible and conductive polyvinyl alcohol (PVA) nanocomposite with vertical graphene nanosheets (VGNs). The bilayer hydrogel sensor demonstrates excellent performance to mimic biological hair cells, responding to acoustic stimuli in the audible range between 60 Hz to 20 kHz. The sensor output demonstrates stable...
Biomimetic ultraflexible piezoresistive flow sensor based on graphene nanosheets and PVA hydrogel
, Article Advanced Materials Technologies ; 2021 ; 2365709X (ISSN) ; Moradi, H ; Wu, S ; Han, Z. J ; Razmjou, A ; Asadnia, M ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Flow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze-like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting...
Computational study of geometric effects of bottom wall microgrooves on cell docking inside microfluidic devices
, Article Journal of Mechanics in Medicine and Biology ; Volume 21, Issue 2 , 2021 ; 02195194 (ISSN) ; Saadatmand, M ; Sharif University of Technology
World Scientific
2021
Abstract
Cells docking inside microfluidic devices is effective in studying cell biology, cell-based biosensing, as well as drug screening. Furthermore, single cell and regularly cells docking inside the microstructure of microfluidic systems are advantageous in different analyses of single cells exposed to equal drug concentration and mechanical stimulus. In this study, we investigated bottom wall microgrooves with semicircular and rectangular geometries with different sizes which are suitable for single cell docking along the length of the microgroove in x-direction and numerous cells docking regularly in one line inside the microgroove in a 3D microchannel. We used computational fluid dynamics to...
Development of ultrasensitive biomimetic auditory hair cells based on piezoresistive hydrogel nanocomposites
, Article ACS Applied Materials and Interfaces ; Volume 13, Issue 37 , 2021 , Pages 44904-44915 ; 19448244 (ISSN) ; Moradi, H ; Pastras, C. J ; Abolpour Moshizi, S ; Wu, S ; Asadnia, M ; Sharif University of Technology
American Chemical Society
2021
Abstract
With an ageing population, hearing disorders are predicted to rise considerably in the following decades. Thus, developing a new class of artificial auditory system has been highlighted as one of the most exciting research topics for biomedical applications. Herein, a design of a biocompatible piezoresistive-based artificial hair cell sensor is presented consisting of a highly flexible and conductive polyvinyl alcohol (PVA) nanocomposite with vertical graphene nanosheets (VGNs). The bilayer hydrogel sensor demonstrates excellent performance to mimic biological hair cells, responding to acoustic stimuli in the audible range between 60 Hz to 20 kHz. The sensor output demonstrates stable...
Viral infected cells reveal distinct polarization behavior; a polarimetric microscopy analysis on HSV infected Vero and HeLa cells
, Article Journal of Quantitative Spectroscopy and Radiative Transfer ; Volume 262 , 2021 ; 00224073 (ISSN) ; Abedini, M ; Badieyan, S ; Vaezjalali, M ; Akhavan, O ; Sasanpour, P ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
The optical polarization properties of virus-infected cells have been measured, analyzed, and compared with the uninfected cells. In this regard, Vero and HeLa cells have been used as the host for Herpes simplex viruses (HSV). By using polarization microscopy imaging technique, the Mueller matrix images of infected and uninfected cells have been recorded. Through image processing and further analysis, the polarization properties of host cells are compared with their infected ones. For quantitative analysis, the multispectral Mueller matrix transformation (MMT) parameters (A and b) are calculated to identify the microstructural differentiations between uninfected and infected cells by HSV....
Time-domain ultrasound as prior information for frequency-domain compressive ultrasound for intravascular cell detection: A 2-cell numerical model
, Article Ultrasonics ; Volume 125 , 2022 ; 0041624X (ISSN) ; Nili, V. A ; Ejtehadi, M ; Savabi, R ; Kavehvash, Z ; Ahmadian, M. T ; Vahdat, B. V ; Sharif University of Technology
Elsevier B.V
2022
Abstract
This study proposes a new method for the detection of a weak scatterer among strong scatterers using prior-information ultrasound (US) imaging. A perfect application of this approach is in vivo cell detection in the bloodstream, where red blood cells (RBCs) serve as identifiable strong scatterers. In vivo cell detection can help diagnose cancer at its earliest stages, increasing the chances of survival for patients. This work combines time-domain US with frequency-domain compressive US imaging to detect a 20-μ MCF-7 circulating tumor cell (CTC) among a number of RBCs within a simulated venule inside the mouth. The 2D image reconstructed from the time-domain US is employed to simulate the...
A large dataset of white blood cells containing cell locations and types, along with segmented nuclei and cytoplasm
, Article Scientific Reports ; Volume 12, Issue 1 , 2022 ; 20452322 (ISSN) ; Saghari, S ; Tavakoli, S ; Rostami, P ; Abaszadeh, M ; Mirzadeh, F ; Satlsar, E. S ; Gheidishahran, M ; Gorgi, F ; Mohammadi, S ; Hosseini, R ; Sharif University of Technology
Nature Research
2022
Abstract
Accurate and early detection of anomalies in peripheral white blood cells plays a crucial role in the evaluation of well-being in individuals and the diagnosis and prognosis of hematologic diseases. For example, some blood disorders and immune system-related diseases are diagnosed by the differential count of white blood cells, which is one of the common laboratory tests. Data is one of the most important ingredients in the development and testing of many commercial and successful automatic or semi-automatic systems. To this end, this study introduces a free access dataset of normal peripheral white blood cells called Raabin-WBC containing about 40,000 images of white blood cells and color...
A new modeling and control scheme for cascaded split-source converter cells
, Article IEEE Transactions on Industrial Electronics ; Volume 69, Issue 8 , 2022 , Pages 7618-7628 ; 02780046 (ISSN) ; Milimonfared, J ; Zolghadri, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
Cascaded split-source inverter (CSSI) is a new single-stage modular multilevel topology. Each cell of this converter converts dc to ac power in the buck or boost operation mode without any additional power switch. This article develops a design method based on a detailed model for CSSI. This model shows that energy storage elements experience double-fundamental frequency ripples besides high-frequency ones. It accurately calculates voltage gains and capacitor voltage and inductor current ripples. On the other hand, common carrier-based multilevel modulations have been modified in terms of both reference and carrier signals to control the inverter under symmetric and asymmetric conditions....
Techno-economic assessment of a novel power-to-liquid system for synthesis of formic acid and ammonia, based on CO2 electroreduction and alkaline water electrolysis cells
, Article Renewable Energy ; Volume 187 , 2022 , Pages 1224-1240 ; 09601481 (ISSN) ; Khalili, M ; Pakzad, P ; Mehrpooya, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The power-to-liquid concept is a promising strategy to convert the power plants' flue gas to value-added liquid fuels using renewable energy. This technology could potentially reduce global greenhouse gases emissions and mitigate the environmental problems associated with the fossil fuels industry. In this regard, the main objective of the present study is to propose a novel power-to-liquid plant for the synthesis of formic acid and ammonia from power plants' flue gas, emphasizing the role of electrochemical technologies and renewable energy. The system's basis is developed by the integration of CO2 electroreduction cell, alkaline water electrolysis cell, and photovoltaic panel technologies....
In vitro study: synthesis and evaluation of Fe3O4/CQD magnetic/fluorescent nanocomposites for targeted drug delivery, MRI, and cancer cell labeling applications
, Article Langmuir ; Volume 38, Issue 12 , 2022 , Pages 3804-3816 ; 07437463 (ISSN) ; Ahmadi, R ; Heydari, M ; Rahimipour, M. R ; Molaei, M. J ; Unsworth, L ; Sharif University of Technology
American Chemical Society
2022
Abstract
In the present study, first, Fe3O4nanoparticles were functionalized using glutaric acid and then composited with CQDs. Doxorubicin (DOX) drug was loaded to evaluate the performance of the nanocomposite for targeted drug delivery applications. The XRD pattern confirmed the presence of characteristic peaks of CQDs and Fe3O4. In the FTIR spectrum, the presence of carboxyl functional groups on Fe3O4/CQDs was observed; DOX (positive charge) is loaded onto Fe3O4/CQDs (negative charge) by electrostatic absorption. FESEM and AFM images showed that the particle sizes of Fe3O4and CQDs were 23-75 and 1-3 nm, respectively. The hysteresis curves showed superparamagnetic properties for Fe3O4and Fe3O4/CQDs...
Droplet-based microfluidics in biomedical applications
, Article Biofabrication ; Volume 14, Issue 2 , 2022 ; 17585082 (ISSN) ; Besanjideh, M ; Nasiri, R ; Shamloo, A ; Nasrollahi, F ; De Barros, N. R ; Davoodi, E ; Erdem, A ; Mahmoodi, M ; Hosseini, V ; Montazerian, H ; Jahangiry, J ; Darabi, M.A ; Haghniaz, R ; Dokmeci, M.R ; Annabi, N ; Ahadian, S ; Khademhosseini, A ; Sharif University of Technology
IOP Publishing Ltd
2022
Abstract
Droplet-based microfluidic systems have been employed to manipulate discrete fluid volumes with immiscible phases. Creating the fluid droplets at microscale has led to a paradigm shift in mixing, sorting, encapsulation, sensing, and designing high throughput devices for biomedical applications. Droplet microfluidics has opened many opportunities in microparticle synthesis, molecular detection, diagnostics, drug delivery, and cell biology. In the present review, we first introduce standard methods for droplet generation (i.e. passive and active methods) and discuss the latest examples of emulsification and particle synthesis approaches enabled by microfluidic platforms. Then, the applications...