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    A microfluidic concentration gradient generator for simultaneous delivery of two reagents on a millimeter-sized sample

    , Article Journal of Flow Chemistry ; Volume 10, Issue 4 , 2020 , Pages 615-625 Rismanian, M ; Saidi, M. S ; Kashaninejad, N ; Sharif University of Technology
    Springer International Publishing  2020
    Microfluidic concentration gradient generators (μCGGs) are indispensable parts of many emerging lab-on-a-chip platforms for biological studies and drug delivery applications. Most of the μCGGs reported in the literature can only generate the desired concentration gradients in a micron-sized sample (e.g., cells). As such, there is an unmet need to design a μCGG that can generate continuous concentration gradients of multi reagents (e.g., drugs) in a millimeter-sized sample (e.g., tissue). Herein, we report the proof-of-concept of this class of μCGG by combining a modified tree-like CGG with a micromixer. By conducting both experimental investigation and numerical analysis, we show that the... 

    Design and Fabrication of Micro-Fluidic Chip for Formation, Culture and Analysis of Cancer Tumor Cell Spheroids

    , M.Sc. Thesis Sharif University of Technology Khoshravesh, Hirad (Author) ; Saeedi, Mohammad Saeed (Supervisor) ; Kazemzadeh Hannani, Siamak (Co-Supervisor)
    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... 

    A new non-dimensional parameter to obtain the minimum mixing length in tree-like concentration gradient generators

    , Article Chemical Engineering Science ; Volume 195 , 2019 , Pages 120-126 ; 00092509 (ISSN) Rismanian, M ; Saidi, M. S ; Kashaninejad, N ; Sharif University of Technology
    Elsevier Ltd  2019
    Microfluidic-based concentration gradient generators (CGGs) have a number of applications in chemical, biological and pharmaceutical studies. Thus, precise design of the microfluidic system is crucial to maintaining the desired concentration gradient in microchannels. One of the design considerations is the length of microchannels in the structure of a CGG. A CGG with a short length fails to provide the complete diffusive mixing, while the size of the microchip would unfavorably increase by incorporating a long CGG. Considering a CGG as a tree-like structure consisting of T-shaped micromixers, the mixing process of the species at a straight microchannel has been solved analytically. Herein,... 

    Design a Microfluidics System for Drug Testing of Leukemia Patient's Bone Marrow Aspirate

    , M.Sc. Thesis Sharif University of Technology Rahimi, Ali (Author) ; Saidi, Mohammad Said (Supervisor)
    Cancer is one of the most causes of mortality in the world. Leukemia is a type of cancer initiated by the rapid proliferation of blood cells including WBCs, RBCs, and Platelets, that classified into four general types of AML, ALL, CML, and CLL. The main treatment of leukemia is chemotherapy. Because of many problems that patients have with this treatment and not so good results of chemotherapy, we design a microfluidic chip that can perform personalized medicine treatment for leukemia patients.This microchip consists of two main parts, Concentration Gradient Generator (CGG), and cell culture. CGG system is a tree CGG with two inlets and four outlets, which makes a linear concentration of... 

    Design and Fabrication of a Microfluidic System for Simultaneous Delivery of Two Reagents on a Millimeter-Sized Tissue

    , Ph.D. Dissertation Sharif University of Technology Rismanian, Milad (Author) ; Saeedi, Mohamad Saeed (Supervisor) ; Kashaninejad, Navid (Co-Supervisor)
    It is of great interest to investigate the effects of different concentrations of chemical species on the behavior of test samples. For example, while developing a new drug, pharmacologists are concerned with the behavior of the live sample against different drug concentrations. Microfluidic systems are the new engineering platforms developed for simplifying these experiments. The main goal of the current study is the design and fabrication of a microfluidic system with the capability of generating a continuous concentration gradient from two species simultaneously on a millimeter-sized test sample. Such a system creates many benefits for researchers using microfluidics technology. Our... 

    A tool for designing tree-like concentration gradient generators for lab-on-a-chip applications

    , Article Chemical Engineering Science ; Volume 212 , 2020 Ebadi, M ; Moshksayan, K ; Kashaninejad, N ; Saidi, M. S ; Nguyen, N. T ; Sharif University of Technology
    Elsevier Ltd  2020
    Concentration gradient generators (CGGs) help biologists to perform large scale, fast and high-throughput experiments. This paper introduces a design tool called Tree-like Concentration gradient generator Design Tool (TCDT). The performance of this tool is validated both numerically and experimentally. Three CGGs were fabricated using three different fabrication methods and design parameters. The performance of these devices was examined using the measurement of fluorescent and dye intensity. The performance of the design tool for non-linear and multi-drug concentration gradient generations was investigated as well. In addition, a method was developed to investigate the multi-drug... 

    Design and Fabrication of a Microfluidic Kidney Nephron-on-Chip Platform

    , M.Sc. Thesis Sharif University of Technology Yahyazadeh Shourabi, Arash (Author) ; Saeedi, Mohammad Saeed (Supervisor) ; Hajilouy Benisi, Ali (Supervisor) ; Moghadas, Hajar (Co-Supervisor)
    In this manuscript, we designed and fabricated a novel integrated microfluidic Kidney Nephron-On-Chip. This chip is able to culture cell monolayers under various fluid shear stresses and divert osmotic pressure gradients while imposing four different concentrations of an injected drug on cells. The multi-layer platform consisting of two bubble-trappers to eliminate all unwanted bubbles from the system, a concentration gradient generator to generate four different concentrations of the injected drug, and a membrane-based cell culture chamber caple of providing renal cells with their in-vivo condition. Using colorimetric techniques, the bubble trapper ability was quantified at flow rates up to... 

    Organ-tumor-on-a-chip for chemosensitivity assay: A critical review

    , Article Micromachines ; Volume 7, Issue 8 , 2016 ; 2072666X (ISSN) Kashaninejad, N ; Nikmaneshi, M. R ; Moghadas, H ; Kiyoumarsi Oskouei, A ; Rismanian, M ; Barisam, M ; Saidi, M. S ; Firoozabadi, B ; Sharif University of Technology
    MDPI AG  2016
    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...