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microfluidics
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Exploring contraction–expansion inertial microfluidic-based particle separation devices integrated with curved channels
, Article AIChE Journal ; Volume 65, Issue 11 , 2019 ; 00011541 (ISSN) ; Abdorahimzadeh, S ; Nasiri, R ; Sharif University of Technology
John Wiley and Sons Inc
2019
Abstract
Separation of particles or cells has various applications in biotechnology, pharmaceutical and chemical industry. Inertial cell separation, in particular, has been gaining a great attention in the recent years since it has exhibited a label-free, high-throughput and efficient performance. In this work, first, an inertial contraction–expansion array microchannel device, capable of passively separating two particles with diameters of 4 and 10 μm, was numerically studied. Then, the validated model was combined with curved geometries in order to investigate the effect of curve features on the separation process. The overall purpose was to investigate the interaction between the two different...
Investigating the effect of reagent parameters on the efficiency of cell lysis within droplets
, Article Physics of Fluids ; Volume 32, Issue 6 , 2020 ; Hassani Gangaraj, M ; Sharif University of Technology
American Institute of Physics Inc
2020
Abstract
Cell lysis is an essential primary step in cell assays. In the process of cell lysis, the cell membrane is destroyed and the substances inside the cell are extracted. By utilizing a droplet-based microfluidic platform for cell lysis, the mixer unit that is required for mixing lysis reagents with the cells can be excluded, and thus, the complexity of the fabrication process is reduced. In addition, lysing the cells within the droplets will prevent the cells from exposure to the channel walls, and as a result, cleanliness of the samples and the device is maintained. In this study, cell lysis within the droplets and the parameters affecting the efficiency of this process are investigated using...
Comparison of logarithmic, elliptic, and conical helical spiral for isolation of circulating tumor cells based on inertial method
, Article Physics of Fluids ; Volume 34, Issue 9 , 2022 ; 10706631 (ISSN) ; Mozhdehbakhsh Mofrad, Y ; Safari, M ; Naseri, T ; Sharif University of Technology
American Institute of Physics Inc
2022
Abstract
Cancer is one of the most significant causes of death in the world. It has been shown that the role of circulating tumor cells (CTCs) in the early detection of cancer is crucial. Since the number of these cancerous cells in blood is very rare, the inertial microfluidic devices are one of the best candidates for the isolation of CTCs because they result in a high throughput process. Consequently, they can process a large volume of blood in a short time. Despite extensive computational and experimental studies on inertial microfluidic platforms, the impact of the curvature has not been thoroughly investigated during separation. In this paper, the feasibility of isolation of CTCs for...
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...
Microfluidic-assisted fiber production: Potentials, limitations, and prospects
, Article Biomicrofluidics ; Volume 16, Issue 6 , 2022 ; 19321058 (ISSN) ; Nilghaz, A ; Saadatmand, M ; Naeimirad, M ; Demello, A. J ; Sharif University of Technology
American Institute of Physics Inc
2022
Abstract
Besides the conventional fiber production methods, microfluidics has emerged as a promising approach for the engineered spinning of fibrous materials and offers excellent potential for fiber manufacturing in a controlled and straightforward manner. This method facilitates low-speed prototype synthesis of fibers for diverse applications while providing superior control over reaction conditions, efficient use of precursor solutions, reagent mixing, and process parameters. This article reviews recent advances in microfluidic technology for the fabrication of fibrous materials with different morphologies and a variety of properties aimed at various applications. First, the basic principles, as...
Developing an Off-the-Shelf microfluidic droplet generation device for cell encapsulation
, Article Industrial and Engineering Chemistry Research ; Volume 61, Issue 30 , 2022 , Pages 10689-10699 ; 08885885 (ISSN) ; Shamloo, A ; Sharif University of Technology
American Chemical Society
2022
Abstract
Droplet microfluidics is a platform of microfluidics in which two immiscible fluids are used to generate droplets for various biomedical applications. This platform introduces several advantages in applications such as cell lysis, cell culture, co-culture, and cell encapsulation. The most important issues regarding droplet generation devices are the fabrication complexity and maintenance of these devices. In this study, a simple and easy-to-fabricate microdroplet generator is designed and fabricated to resolve these issues. Furthermore, since this device is easy to fabricate and use, it can play a key role in the fabrication of medical devices for controlling infectious diseases in poor and...
Integrating hydrodynamic and acoustic cell separation in a hybrid microfluidic device: a numerical analysis
, Article Acta Mechanica ; Volume 233, Issue 5 , 2022 , Pages 1881-1894 ; 00015970 (ISSN) ; Dizani, M ; Shamloo, A ; Sharif University of Technology
Springer
2022
Abstract
Cell separation microfluidic devices have evolved into a multitude of biomedical and clinical research. Nonetheless, many critical issues remain in the way of achieving an excellent separation of target cells from a heterogeneous sample. Parallel to the abundant experimental studies related to the hybrid microfluidic methods, it is easy to perceive the lack of numerical investigations in order to optimize the separation process and its accuracy. In this study, for the first time to the best of our knowledge, a hybrid system by integrating acoustophoresis and pinched-flow fractionation (PFF) is proposed to achieve a viable system for a wide-range, precise separation. Employing the ultrasound...
Separation of Metal Ions-based Microfluidic Platform for Liquid-liquid Extraction
, M.Sc. Thesis Sharif University of Technology ; Mohammadi, Ali Asghar (Supervisor) ; Karimi Sabet, Javad (Co-Advisor)
Abstract
Continuous separation processes in microfluidic devices experienced a steep rise in attention during the last two decades. Among the different separation processes, liquid-liquid extraction especially benefits from the short molecular diffusion distance and large specific interfacial area, as these are advantageous for effective mass transport. In the present study, glass-based microfluidic devices have been fabricated utilizing laser ablation and wet chemical etching methods then experiments and numerical simulation were carried out to investigate hydrodynamic behavior of fluid flow in Y-junction microfluidic. In order to achieve phase separation at the end of the microchannel, a phase...
Designing and Developing an Active Micromixer Based on Optical Tweezers for Microfluidics
, M.Sc. Thesis Sharif University of Technology ; Seyed Reihani, Nader (Supervisor)
Abstract
Microfluidics is a field of science that studies micron-scale characteristics of fluids. In this scale fluids show fascinating behavior far beyond our expectation compared to their large-scale counterparts. One of such peculiar behavior is the mixing of two different liquids flowing inside a microchannel. Due to low Reynolds number, the flow inside such a channel would be dominated by laminar behavior. In this regime mixing of the fluids is only mediated by molecular diffusion which is a rather slow process. In the current thesis, we utilized the rotating ability of optical tweezers to construct an active micromixer for Microfluidics. In order to do this we used birefringent microbeads. The...
Design and Simulation of a Passive Microfluidic Device for Particle Separation
, M.Sc. Thesis Sharif University of Technology ; Shamloo, Amir (Supervisor)
Abstract
Nowadays, separation and filtration of particles has many industrial applications in biology and medicine. In this thesis, passive microfluidics are designed and simulated which are able to separate and filter particles. Although particles aer generally expected to follow laminar flow streamlines in the absence of external forces, inertial forxes van cause particles to migrate across mictochannels in an accurate and predictable manner. The effect of these forces is invedtigated, and by using previous research, a model is developed to predict these forces. First design is a microchannel with Archimedean spiral which utilizes both inertial forces and Dean flow to separate particles in the...
Design and Fabrication of Impedance Flowcytometric based Microfluidic Sorter
, M.Sc. Thesis Sharif University of Technology ; Fardmanesh, Mehdi (Supervisor)
Abstract
Microfluidic technology is a field of science that deals with the design, fabrication, and experimental tests of small-scale fluid systems and has made great strides over the past decade. As an interdisciplinary field, this growing field of technology has many applications in medicine, diagnostics, chemical analysis, electronics industry, etc. One of the primary applications of the microfluidic devices is the development of " laboratory on-chip (LOC)" tools as point-of-care (POC) diagnostic tools, such as, rapid detection during surgery. A LOC device includes various application modules, sample transfer and preparation modules, separation modules, and detection and analysis modules. The...
Analytical relations for long-droplet breakup in asymmetric T junctions
, Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 91, Issue 5 , May , 2015 ; 15393755 (ISSN) ; Moosavi, A ; Hannani, S. K ; Sharif University of Technology
American Physical Society
2015
Abstract
We develop accurate analytical relations for the droplet volume ratio, droplet length during breakup process, and pressure drop of asymmetric T junctions with a valve in each of the branches for producing unequal-sized droplets. An important advantage of this system is that after manufacturing the system, the size of the generated droplets can be changed simply by adjusting the valves. The results indicate that if the valve ratio is smaller than 0.65, the system enters a nonbreakup regime. Also the pressure drop does not depend on the time and decreases by increasing the valve ratio, namely, opening the degree of valve 1 to valve 2. In addition, the results reveal that by decreasing...
Simulation of droplet trains in microfluidic networks
, Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 82, Issue 3 , September , 2010 ; 15393755 (ISSN) ; Seyed Allaei, H ; Ejtehadi, M. R ; Sharif University of Technology
2010
Abstract
We show that in a microfluidic network with low Reynolds numbers, a system can be irreversible due to hysteresis effects. We simulated a network of pipes that was used in a recent experiment. The network consists of one loop connected to input and output pipes. A train of droplets enters the system at a uniform rate, but the droplets may leave the system in a periodic or even a chaotic pattern. The output pattern depends on the time interval between incoming droplets as well as the network geometry. For some parameters, the system is not reversible
A comparison of different geometrical elements to model fluid wicking in paper-based microfluidic devices
, Article AIChE Journal ; Volume 66, Issue 1 , 2020 ; Shamloo, A ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
Recently, microfluidic paper-based analytical devices (μPADs) have outstripped polymeric microfluidic devices in the ease of fabrication and simplicity. Surface tension-based fluid motion in the paper's porous structure has made the paper a suitable substrate for multiple biological assays by directing fluid into multiple assay zones. The widespread assumption in most works for modeling wicking in a paper is that the paper is a combination of capillaries with the same diameter equal to the effective pore diameter. Although assuming paper as a bundle of capillaries gives a good insight into pressure force that drives the fluid inside the paper, there are some difficulties using the effective...
Microfluidics Desulfurization of Hydrocarbons Components
, M.Sc. Thesis Sharif University of Technology ; Mohammadi, Aliasghar (Supervisor) ; Kazemeini, Mohammad (Supervisor)
Abstract
Microfluidic is a science and technology in which they study the behavior of fluids, control them and design devices or systems with dimensions of tens to hundreds of micrometers. The technology has the ability to design and manufacture macro-scale and micro-scale equipment, such as micro-pumps, micro-valves, micro-filters, micro-mixers, micro-reactors, and other equipment. The benefits of this technology include the use of low sample size, low waste of energy, low power consumption, short response time, high system performance, portability and performance of several operating phases in a compressed piece such as production, isolation and analysis. Also, the very low amount of chemicals and...
Design and Fabrication of Micro-Fluidic Chip for Formation, Culture and Analysis of Cancer Tumor Cell Spheroids
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor) ; Kazemzadeh Hannani, Siamak (Co-Supervisor)
Abstract
Simulating the in-vivo environment of cancer tumors outside the body, can provide an appropriate condition for studying different key processes of the tumor micro-environment, such as aggregation, formation, growth, angiogenesis and metastasis of the cancer tumor cells, which can be useful in finding methods to cure, or at least control cancer. Every year, a variety of drugs are being developed to overcome cancer, all of which need to be experimented. Although, these drugs are now experimented on animals, and some human volunteers, the reaction of different patients’ cancer cells to different drugs may differ with the experimented animals, or even with other people. So, there needs to be a...
Cell-cell interactions mediate cytoskeleton organization and collective endothelial cell chemotaxis
, Article Cytoskeleton ; Vol. 71, issue. 9 , 2014 , p. 501-512 ; Sharif University of Technology
Abstract
This study investigates the role of cell-cell and cell-ligand interactions in cytoskeleton organization of endothelial cells (ECs) and their directional migration within a microfluidic device. The migration of ECs in response to a biochemical factor was studied. Mathematical analysis of the cell migration pathways and cellular cytoskeleton revealed that directional migration, migration persistence length, migration speed, and cytoskeletal stress fiber alignment can be mediated by the level of cell contacts as well as the presence or absence of a biochemical polarizing factor. It was shown that in the presence of a biochemical polarizing factor, higher cell density and more frequent cell...
Microfluidic manipulation of Core/Shell nanoparticles for oral delivery of chemotherapeutics: A new treatment approach for colorectal cancer
, Article Advanced Materials ; Volume 28, Issue 21 , 2016 , Pages 4134-4141 ; 09359648 (ISSN) ; Taranejoo, S ; Dashtimoghadam, E ; Bahlakeh, G ; Majedi, F.S ; Vandersarl, J. J ; Janmaleki, M ; Sharifi, F ; Bertsch, A ; Hourigan, K ; Tayebi, L ; Renaud, P ; Jacob, K. I ; Sharif University of Technology
Wiley-VCH Verlag
Abstract
A microfluidics approach to synthesize core-shell nanocarriers with high pH tunability is described. The sacrificial shell protects the core layer with the drugs and prevents their release in the severe pH conditions of the gastrointestinal tract, while allowing for drug release in the proximity of a tumor. The proposed nanoparticulate drug-delivery system is designed for the oral administration of cancer therapeutics
Immobilization of functionalized gold nanoparticles in a well-organized silicon-based microextracting chip followed by online thermal desorption-gas chromatography
, Article Microchemical Journal ; Volume 143 , 2018 , Pages 205-211 ; 0026265X (ISSN) ; Bagheri, H ; Zamani, C ; Sharif University of Technology
Elsevier Inc
2018
Abstract
In this survey, firstly, a silicon wafer-based microchip, possessing a 50-cm microchannel with the dimensions of 120 and 60 μm, was manufactured by chemical etching technique. Subsequently, the inner surface of the microchannel was coated with a primary layer of gold nanoparticles synthesized by galvanic displacement. Then a self-assembled monolayer of 3-mercaptopropyltriethoxysilane was immobilized on the first layer. Eventually, a polydimethylsiloxane film with a thickness of 16 ± 1 μm was formed on the walls of the microchannel by means of sol-gel method. Field emission scanning electron microscopy and atomic force microscopy were extensively employed to investigate the status of both...
Novel approaches in cancer management with circulating tumor cell clusters
, Article Journal of Science: Advanced Materials and Devices ; Volume 4, Issue 1 , 2019 , Pages 1-18 ; 24682284 (ISSN) ; Kashaninejad, N ; Moshksayan, K ; Saidi, M. S ; Firoozabadi, B ; Nguyen, N. T ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Tumor metastasis is responsible for the vast majority of cancer-associated morbidities and mortalities. Recent studies have disclosed the higher metastatic potential of circulating tumor cell (CTC) clusters than single CTCs. Despite long-term study on metastasis, the characterizations of its most potent cellular drivers, i.e., CTC clusters have only recently been investigated. The analysis of CTC clusters offers new intuitions into the mechanism of tumor metastasis and can lead to the development of cancer diagnosis and prognosis, drug screening, detection of gene mutations, and anti-metastatic therapeutics. In recent years, considerable attention has been dedicated to the development of...