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fluidic-devices
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Use of the freely-swimming, Serratia marcescens bacteria to enhance mixing in microfluidic systems
, Article ASME 2009 International Mechanical Engineering Congress and Exposition, 13 November 2009 through 19 November 2009 ; Volume 12, Issue PART A , 2010 , Pages 463-467 ; 9780791843857 (ISBN) ; Shafii, M. B ; Rasoulian, R ; Jamalifar, H ; Fazeli, M. R ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
Abstract
Mixing has become a challenge in micro-fluidic systems because of the low Reynolds number in micro-channels. The method which is implemented in this paper is to use freely-swimming bacteria to enhance the mixing process. Accordingly, the Serratia marcescens bacteria were used for this matter. The mixing performance of the system is quantified by measuring the diffusion rate of Rhodamine B in a particular section of a channel connected to a chamber with varying Rhodamine B concentration. The concentration of Rhodamine B was measured using the Laser Induced Fluorescence (LIF) technique. The channel is in the form of a pipe and is closed on the extending side. In this paper, it is demonstrated...
Unidirectional transport of water through an asymmetrically charged rotating carbon nanotube
, Article Journal of Physical Chemistry C ; Volume 121, Issue 42 , 2017 , Pages 23649-23658 ; 19327447 (ISSN) ; Moosavi, A ; Sharif University of Technology
Abstract
Achieving a high speed, unidirectional water flow through carbon nanotubes (CNTs) is a key factor in designing novel nanofluidic devices. In this study, utilizing molecular dynamics (MD) simulations, we propose a novel nanoscale water pump for directed water transportation using charged rotating CNTs. Two basic conditions for stable water flow, including thermodynamic nonequilibrium and spatial asymmetry, are provided by introducing partial charges on carbon atoms of the channel with asymmetric patterns and its rotation, respectively. We demonstrate that the performance of the water pump is proportional to the gradient of a linear charge distribution and angular velocity of the rotation. Our...
Treatment of the small time instability in the finite element analysis of fluid structure interaction problems
, Article International Journal for Numerical Methods in Fluids ; Volume 71, Issue 6 , 2013 , Pages 756-771 ; 02712091 (ISSN) ; Movahhedy, M. R ; Sharif University of Technology
2013
Abstract
In this paper, the fluid-structure interaction problem in mechanical systems in which a high frequency vibrating solid structure interacts with the surrounding fluid flow is considered. Such a situation normally appears in many microelectromechanical systems like a wide variety of microfluidic devices. A different implementation of the residual-based variational multiscale flow method is employed within the arbitrary Lagrangian-Eulerian formulation. The combination of the variational multiscale method with appropriate stabilization parameters is used to handle the so-called small time step instability in the finite element analysis of the fluid part in the coupled fluid-structure interaction...
Toward higher extraction and enrichment factors via a double-reservoirs microfluidic device as a micro-extractive platform
, Article Journal of Separation Science ; Volume 42, Issue 18 , 2019 , Pages 2985-2992 ; 16159306 (ISSN) ; Baraazandeh, M ; Bagheri, H ; Sharif University of Technology
Wiley-VCH Verlag
2019
Abstract
In this study, firstly, a double-reservoir and switchable prototype of a micro-chip along with the respective holders were fabricated. A cyclic desorption process using microliter volume of organic solvent was adopted to prevent any outdoor contamination. As extractive phases, two identical sheets of electrospun polyamide/polypyrrole/titania nanofibers were synthesized using core–shell electro-spinning technique and utilized for determination of memantine in plasma samples. Field emission scanning electron microscopy images showed a high degree of porosity and homogeneity throughout the sheet structure. Also, energy dispersive X-ray analysis confirmed the presence of titania, while the...
Toward a comprehensive microextraction/determination unit: A chip silicon rubber polyaniline-based system and its direct coupling with gas chromatography and mass spectrometry
, Article Journal of Separation Science ; Volume 39, Issue 21 , 2016 , Pages 4227-4233 ; 16159306 (ISSN) ; Allahdadlalouni, M ; Zamani, C ; Sharif University of Technology
Wiley-VCH Verlag
2016
Abstract
An inexpensive silicon rubber-based chip was constructed by fabricating a triangle-shaped microcanal with a 135 μm width and 234 μm depth by laser ablation technique. The fabricated groove was sealed by a thin glass cover while two pieces of stainless-steel tubing were connected to each side of the canal. Then, a thin polyaniline film was synthesized on the walls of the canal by chemical oxidation using a syringe pump to deliver the relevant reagents. The microfluidic system was eventually connected to a gas chromatography-mass spectrometry. To evaluate the capability of the constructed microfluidic system, it was implemented to the analysis of submilliliter volumes of environmental samples...
The effects of thymus plant extracts on single breast cancer cell morphology in the microfluidic channel
, Article 2018 IEEE EMBS Conference on Biomedical Engineering and Sciences, IECBES 2018, 3 December 2018 through 6 December 2018 ; 2019 , Pages 647-651 ; 9781538624715 (ISBN) ; Mansor, M. A ; Alsadat Rad, M ; Soo-Beng Khoo, A ; Ahmad, M ; Marzuki, M ; Physiological Measurement; Sarawak Convention Bureau ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Microfluidics based systems could be useful for drug discovery as they allow for miniaturization and could potentially be run as multiple parallel cell based assays. Such miniaturization allows assays at single cell level and reduces the amount of test material needed, which, in the case of natural product extracts, simplifies the preparation. Thyme species extracts have been reported to show some promising anti-cancer effects. In the present work, we used a microfluidics based system to study the effects of Thymus kotschyanusm Boiss plant extract on two human breast cancer cells lines which are MDA-MB-231 and MCF-7. For better understanding a single cancer cell death mechanism and a flow...
Spheroids-on-a-chip: recent advances and design considerations in microfluidic platforms for spheroid formation and culture
, Article Sensors and Actuators, B: Chemical ; Volume 263 , 15 June , 2018 , Pages 151-176 ; 09254005 (ISSN) ; Kashaninejad, N ; Ebrahimi Warkiani, M ; Lock, J. G ; Moghadas, H ; Firoozabadi, B ; Saidi, M. S ; Nguyen, N. T ; Sharif University of Technology
Elsevier B.V
2018
Abstract
A cell spheroid is a three-dimensional (3D) aggregation of cells. Synthetic, in-vitro spheroids provide similar metabolism, proliferation, and species concentration gradients to those found in-vivo. For instance, cancer cell spheroids have been demonstrated to mimic in-vivo tumor microenvironments, and are thus suitable for in-vitro drug screening. The first part of this paper discusses the latest microfluidic designs for spheroid formation and culture, comparing their strategies and efficacy. The most recent microfluidic techniques for spheroid formation utilize emulsion, microwells, U-shaped microstructures, or digital microfluidics. The engineering aspects underpinning spheroid formation...
Simulation of blood particle separation in a trapezoidal microfluidic device by acoustic force
, Article IEEE Transactions on Electron Devices ; Volume 66, Issue 3 , 2019 , Pages 1495-1503 ; 00189383 (ISSN) ; Yazdan Parast, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Nowadays, the importance of the blood particles separation is undeniable in medical fields and there are different sorts of separation methods accordingly. Acoustic cell separation is chosen in this paper. Also, numerical methods have been used to study the effect of geometrical factors on the separation of the particles before spending time and expenses in a trial and error manner experimentally. We have implemented a plenary finite-element-based simulation of separatingblood particles such as white blood cells and platelets in an acoustic field using standing surface acoustic waves. In this paper, unlike previous works in which the channel is rectangular; the channel is trapezoidal in...
Simple, Cost-effective, and continuous 3D dielectrophoretic microchip for concentration and separation of bioparticles
, Article Industrial and Engineering Chemistry Research ; Volume 59, Issue 9 , 2020 , Pages 3772-3783 ; Saidi, M. S ; Kashaninejad, N ; Nguyen, N. T ; Sharif University of Technology
American Chemical Society
2020
Abstract
Dielectrophoresis is a robust approach for manipulating bioparticles in microfluidic devices. In recent years, many groups have developed dielectrophoresis-based microfluidic systems for separation and concentration of various types of bioparticles, where the gradient of the electric field causes dielectrophoresis force acting on the suspended particles. Enhancing the gradient of the electric field with three-dimensional (3D) electrodes can significantly improve the efficiency of the system. Implementing planar electrodes in a 3D arrangement is a simple option to form a 3D-electrode configuration. This paper reports the development of a novel dielectrophoretic microfluidic system for...
Silane–based modified papers and their extractive phase roles in a microfluidic platform
, Article Analytica Chimica Acta ; Volume 1128 , 2020 , Pages 31-41 ; Rezvani, O ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Herein, some (modified) paper–based substrates were prepared and utilized as extractive phases in a microfluidic device and their extraction performances examined for analytes with different polarities. Reagents including hexadecyltrimethoxysilane (HDTMS), phenyltrimethoxysilane (PTES), (3-aminopropyl) triethoxysilane (APTES) and 3–(2,3–epoxypropoxy) propyltrimethoxysilane (EPPTMOS) were implemented for the modification process. Due to the induction of different silane functional groups, it was anticipated to have various interactions for the tested analytes. Eventually, the prepared paper sheets were used as extractive phases for solid–phase extraction within a microfluidic system. The...
Shear-thinning droplet formation inside a microfluidic T-junction under an electric field
, Article Acta Mechanica ; Volume 232, Issue 7 , 2021 , Pages 2535-2554 ; 00015970 (ISSN) ; Honarmand, M ; Dizani, M ; Moosavi, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
Springer
2021
Abstract
Researchers usually simplify their simulations by considering the Newtonian fluid assumption in microfluidic devices. However, it is essential to study the behavior of real non-Newtonian fluids in such systems. Moreover, using the external electric or magnetic fields in these systems can be very beneficial for manipulating the droplet size. This study considers the simulation of the process of non-Newtonian droplets’ formation under the influence of an external electric field. The novelty of this study is the use of a shear-thinning fluid as the droplet phase in this process, which has been less studied despite its numerous applications. The effects of an external electric field on this...
Secondary flows, mixing, and chemical reaction analysis of droplet-based flow inside serpentine microchannels with different cross sections
, Article Langmuir ; Volume 37, Issue 17 , 2021 , Pages 5118-5130 ; 07437463 (ISSN) ; Madadelahi, M ; Dizani, M ; Shamloo, A ; Sharif University of Technology
American Chemical Society
2021
Abstract
Chemical bioreactions are an important aspect of many recent microfluidic devices, and their applications in biomedical science have been growing worldwide. Droplet-based microreactors are among the attractive types of unit operations, which utilize droplets for enhancement in both mixing and chemical reactions. In the present study, a finite-volume-method (FVM) numerical investigation is conducted based on the volume-of-fluid (VOF) applying for the droplet-based flows. This multiphase computational modeling is used for the study of the chemical reaction and mixing phenomenon inside a serpentine microchannel and explores the effects of the aspect ratio (i.e., AR = height/width) of...
Pumping effect of bubble growth and collapse in microchannels: Thermo-hydraulic modeling
, Article Scientia Iranica ; Volume 19, Issue 3 , June , 2012 , Pages 431-436 ; 10263098 (ISSN) ; Saidi, M. H ; Sharif University of Technology
2012
Abstract
In the past two decades, microfluidic systems have become more appealing due to their wide applications in many areas, such as electronics, biotechnology, medicine, etc. Recently, the advantages of using the bubble growth phenomenon as a robust actuator in microfluidic devices have directed research interests towards the investigation of various applications. In this research, a new transient thermo-hydraulic model has been developed for bubble growth in confined volumes. The present model has been used to describe the pumping effect produced by the bubble growth and collapse phenomenon in microchannels. The results show relatively good agreement with experimental data. This study is useful...
Production of uniform size cell-enclosing silk derivative vehicles through coaxial microfluidic device and horseradish crosslinking reaction
, Article European Polymer Journal ; Volume 172 , 2022 ; 00143057 (ISSN) ; Hosseini, M ; Varaa, N ; Mahmoodi, N ; Goodarzi, A ; Taghdiri Nooshabadi, V ; Hassanzadeh, S ; Arabpour, Z ; Khanmohammadi, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Silk fibroin (SF) as a natural biopolymer holds great potential in biomedical research because of its biocompatibility, easy processability and high strength properties. However, slow gelation time has narrowed its applications, specifically in cell-laden microparticle production due to insufficient crosslinkable moieties. This study aimed to develop cell-laden silk fibroin-phenol (SF-Ph) microparticle through co-flow microfluidic system using SF conjugated Ph moieties whereas covalent crosslinking is mediated with horseradish peroxidase (HRP) in the presence of hydrogen peroxide (H2O2). For this, the SF-Ph was synthesized through carbodiimide condensation crosslinking reaction. Aqueous...
Polyamide/titania hollow nanofibers prepared by core–shell electrospinning as a microextractive phase in a fabricated sandwiched format microfluidic device
, Article Journal of Chromatography A ; Volume 1528 , 2017 , Pages 1-9 ; 00219673 (ISSN) ; Hashemi Hedeshi, M ; Bagheri, H ; Sharif University of Technology
Abstract
In this study, a low–cost microfluidic device from polymethyl methacrylate was fabricated by laser engraving technique. The device is consisted of a central chip unit with an aligned microchannel. Both sides of the engraved microchannel were sandwiched by two synthesized sheets from polyamide/titania (PA/TiO2) hollow nanofibers as extractive phases. The inlet and outlet of the device were connected to the polyether ether ketone tubes, while a peristaltic pump was used to deliver both sample and desorbing solvent through the microchannel. The recorded scanning electron microscopy images from the surface of the synthesized PA/TiO2 nanofibers, exhibit a good degree of homogeneity and porosity...
Particles focusing and separation by a novel inertial microfluidic device: divergent serpentine microchannel
, Article Industrial and Engineering Chemistry Research ; Volume 61, Issue 38 , 2022 , Pages 14324-14333 ; 08885885 (ISSN) ; Shamloo, A ; Vatani, P ; Ebrahimi, S ; Sharif University of Technology
American Chemical Society
2022
Abstract
Microfluidic experiments have found wide applications in medical sciences and engineering, such as cell separation and focusing. In the present study, focusing and separation of particles with different sizes and densities were investigated by designing inertial microfluidic devices. The microfluidic channel is designed by analyzing the induced forces on the particles. In the designing process, the objective was to focus and separate the particles in the shortest length of the channel with the lowest possible cycles and high efficiency. The simulation is then used for analyzing the two proposed geometries to evaluate their particle separation and focusing ability, named convergent and...
Parametric study on mixing process in an in-plane spiral micromixer utilizing chaotic advection
, Article Analytica Chimica Acta ; Volume 1022 , 2018 , Pages 96-105 ; 00032670 (ISSN) ; Shamloo, A ; Sharif University of Technology
Abstract
Recent advances in the field of microfabrication have made the application of high-throughput microfluidics feasible. Mixing which is an essential part of any miniaturized standalone system remains the key challenge. This paper proposes a geometrically simple micromixer for efficient mixing for high-throughput microfluidic devices. The proposed micromixer utilizes a curved microchannel (spiral microchannel) to induce chaotic advection and enhance the mixing process. It is shown that the spiral microchannel is more efficient in comparison to a straight microchannel, mixing wise. The pressure drop in the spiral microchannel is only slightly higher than that in the straight microchannel. It is...
Parametric study of droplet formation and characteristics within microfluidic devices - A case study
, Article International Journal of Applied Mechanics ; Volume 12, Issue 7 , 2020 ; Shamloo, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
World Scientific
2020
Abstract
Droplet-based microfluidics technologies hold great attention in a wide range of applications, including chemical analysis, drug screening, and food industries. This work aimed to describe the effects of different physical properties of the two immiscible phases on droplet formation in a flow-focusing microfluidic device and determining proper flow rates to form a droplet within the desired size range. A numerical model was developed to solve the governing equations of two-phase flow and the results were validated with previous experimental results. The results demonstrate different types of droplet formation regimes from dripping to jetting and different production rates of droplets as a...
Parallel in-vitro and in-vivo techniques for optimizing cellular microenvironments by implementing biochemical, biomechanical and electromagnetic stimulations
, Article Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS ; 2012 , Pages 1397-1400 ; 1557170X (ISSN) ; 9781424441198 (ISBN) ; Heibatollahi, M ; Ghafar Zadeh, E
2012
Abstract
Development of novel engineering techniques that can promote new clinical treatments requires implementing multidisciplinary in-vitro and in-vivo approaches. In this study, we have implemented microfluidic devices and in-vivorat model to study the mechanism of neural stem cell migration and differentiation.These studies can result in the treatment of damages to the neuronal system. In this research, we have shown that by applying appropriate ranges of biochemical and biomechanical factors as well as by exposing the cells to electromagnetic fields, it is possible to improve viability, proliferation, directional migration and differentiation of neural stem cells. The results of this study can...
Organ-tumor-on-a-chip for chemosensitivity assay: A critical review
, Article Micromachines ; Volume 7, Issue 8 , 2016 ; 2072666X (ISSN) ; Nikmaneshi, M. R ; Moghadas, H ; Kiyoumarsi Oskouei, A ; Rismanian, M ; Barisam, M ; Saidi, M. S ; Firoozabadi, B ; Sharif University of Technology
MDPI AG
2016
Abstract
With a mortality rate over 580,000 per year, cancer is still one of the leading causes of death worldwide. However, the emerging field of microfluidics can potentially shed light on this puzzling disease. Unique characteristics of microfluidic chips (also known as micro-total analysis system) make them excellent candidates for biological applications. The ex vivo approach of tumor-on-a-chip is becoming an indispensable part of personalized medicine and can replace in vivo animal testing as well as conventional in vitro methods. In tumor-on-a-chip, the complex three-dimensional (3D) nature of malignant tumor is co-cultured on a microfluidic chip and high throughput screening tools to evaluate...