Search for: lab-on-a-chip
Total 38 records
Rheology Effects on Reaction-diffusion Mechanisms in a Y-shaped Micro Fluidic Mixer, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Hassan ; Kazemzadeh Hannani, Siamak
Numerous applications of Lab on a Chips (LOCs) in chemical/biochemical analyses as well as the emergence of advanced methods for their manufacture attracts many researchers’ attention to these micro instruments. Low sample volume consumption and their high controllability are accounted as the main advantage of LOC systems. Micromixers are among the main components of any LOC in which mixing and/or reaction among two components occur. Micromixers have many potential applications in biological and medical sciences, and so they are repeatedly charged by biofluids. Due to sensibility of biofluids, to avoid disintegration, applying electroosmotic flow instead of pressure-induced flow has priority...
Separation and Microfluidic Analysis of one Cancer Biomarker (Exosome) by Means of Microfluidic Chip Microfluidc Analysis Exosome Toward Liquid Biopsy for Cancer Tumor Cell, M.Sc. Thesis Sharif University of Technology ; Saidi, Mohammad Said ; Firouzabadi, Bahar
The recent breakthroughs in the lab-on-a-chip technology will not be directly used as clinical devices unless the specific applications are carefully tested and certified. As there is a growing trend towards microfluidic devices for biomedical research, an active microfluidic device was developed. Common microfabrication methods were used to develop a microchip to separate and concentrate exosome and particular cell based on the dielectrophoresis phenomenon. Unique capabilities of the dielectrophoresis phenomenon make it a powerful tool for micro particle manipulation in micro scale. In this research, geometry for the mentioned purpose is designed and optimized. Three-dimensional...
Design and Simulation of CMOS Based Magnetic Sensor for Biosensing Applications, M.Sc. Thesis Sharif University of Technology ; Akbari, Mahmood ; Fotowat-Ahmady, Ali
This paper presents a scalable and ultrasensitive magnetic biosensing scheme based on on-chip LC resonance frequency-shifting. The sensor transducer gain is demonstrated as being location-dependent on the sensing surface and proportional to the local polarization magnetic field strength |B|2 generated by the sensing inductor. To improve the gain uniformity, a periodic coil is proposed as a substitution for the standard process coil. As an implementation example, the circuit is designed in a 65nm CMOS process. The spatially uniform sensor gain of the array is verified by COMSOL simulations. Overall, the presented sensor demonstrates an improvement in the uniformity of the inductor’s magnetic...
Numerical Study of Enhancement of Inflection Point Focusing for Blood Cell Separation, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali ; Sadrhosseini, Hani
Today, the determination and therapy of numerous illnesses, including malignant growth, relies upon the information and assessment of platelets, so blood testing and cell examination is fundamental to survey the movement of disease. The lab on a chip innovation is utilized as an extremely productive device in cell studies. The lab on a chip is used as a foundation and a substrate for making a legitimate stream for cell processes in medication. This innovation is a gadget or framework with millimeters or centimeters aspects like a chip, and it performs research facility handling on a micron-scale. In spite of the fact that it has a few impediments, it has so many values; for example, it...
Design and Manufacturing of a Setup for Solid-state Nanopore Fabrication, M.Sc. Thesis Sharif University of Technology ; Akbari, Javad ; Taghipour, Mojtaba
The aim of the current research is to study the process of making a solidstate nanopore by molding from PDMS polymer and to make a laboratory sample of a solidstate nanopore manufacturing device using this method. Solid-state nanopores are used to control ion transport in microfluidic channels,lab-on-a-chip detection to study nucleic acids and proteins, desalination, nanofluidic transistors,single-cell sensing tools, and particle classification. In general, the smaller the nanopore, the shorter the length and the higher the mechanical stability, the better the performance. In this research, chips have been made on which there is a blade with a sharpness of 10 nanometers and a height of 10...
Temperature rise in electroosmotic flow of typical non-newtonian biofluids through rectangular microchannels, Article Journal of Heat Transfer ; Volume 136, Issue 3 , March , 2014 ; ISSN: 00221481 ; Sadeghi, A ; Saidi, M. H ; Chakraborty, S ; Sharif University of Technology
Electroosmosis is the main mechanism for flow generation in lab-on-a-chip (LOC) devices. The temperature rise due to the Joule heating phenomenon, associated with the electroosmosis, may be detrimental for samples being considered in LOCs. Hence, a complete understanding of the heat transfer physics associated with the electroosmotic flow is of high importance in design and active control of LOCs. The objective of the present study is to estimate the temperature rise and the thermal entry length in electroosmotic flow through rectangular microchannels, having potential applications in LOC devices. Along this line, the power-law rheological model is used to account for non-Newtonian behavior...
3D modeling of reaction-diffusion dynamics in an electrokinetic Y-shaped microreactor, Article Sensors and Actuators, B: Chemical ; Volume 235 , 2016 , Pages 343-355 ; 09254005 (ISSN) ; Saidi, M. H ; Sadeghi, A ; Sharif University of Technology
We perform a 3D numerical modeling of reaction-diffusion dynamics in a Y-shaped microreactor, considering a fully developed combined electroosmotic and pressure-driven flow. The governing equations, based on a second-order irreversible reaction, are solved invoking a finite-volume approach for a non-uniform grid system. We demonstrate that the reaction is highly position dependent: more production is observed adjacent to the horizontal walls for a favorable pressure gradient, whereas both the wall and centerline are the regions of highest production when a back pressure is applied. We further show that, to achieve the maximum production rate, the EDL should be thick enough, the pressure...
Challenge in particle delivery to cells in a microfluidic device, Article Drug Delivery and Translational Research ; Volume 8, Issue 3 , 2018 , Pages 830-842 ; 2190393X (ISSN) ; Saidi, M. S ; Kashaninejad, N ; Nguyen, N. T ; Sharif University of Technology
Springer Verlag 2018
Micro and nanotechnology can potentially revolutionize drug delivery systems. Novel microfluidic systems have been employed for the cell culture applications and drug delivery by micro and nanocarriers. Cells in the microchannels are under static and dynamic flow perfusion of culture media that provides nutrition and removes waste from the cells. This exerts hydrostatic and hydrodynamic forces on the cells. These forces can considerably affect the functions of the living cells. In this paper, we simulated the flow of air, culture medium, and the particle transport and deposition in the microchannels under different angles of connection inlet. It was found that the shear stress induced by the...
Design and simulation of a microfluidic device for acoustic cell separation, Article Ultrasonics ; Volume 84 , March , 2018 , Pages 234-243 ; 0041624X (ISSN) ; Boodaghi, M ; Sharif University of Technology
Elsevier B.V 2018
Experimental acoustic cell separation methods have been widely used to perform separation for different types of blood cells. However, numerical simulation of acoustic cell separation has not gained enough attention and needs further investigation since by using numerical methods, it is possible to optimize different parameters involved in the design of an acoustic device and calculate particle trajectories in a simple and low cost manner before spending time and effort for fabricating these devices. In this study, we present a comprehensive finite element-based simulation of acoustic separation of platelets, red blood cells and white blood cells, using standing surface acoustic waves...
Modeling, simulation, and employing dilution–dialysis microfluidic chip (DDMC) for heightening proteins refolding efficiency, Article Bioprocess and Biosystems Engineering ; Volume 41, Issue 5 , 2018 , Pages 707-714 ; 16157591 (ISSN) ; Masoudi, M. M ; Shamloo, A ; Habibi Rezaei, M ; Moosavi Movahedi, A. A ; Sharif University of Technology
Springer Verlag 2018
Miniaturized systems based on the principles of microfluidics are widely used in various fields, such as biochemical and biomedical applications. Systematic design processes are demanded the proper use of these microfluidic devices based on mathematical simulations. Aggregated proteins (e.g., inclusion bodies) in solution with chaotropic agents (such as urea) at high concentration in combination with reducing agents are denatured. Refolding methods to achieve the native proteins from inclusion bodies of recombinant protein relying on denaturant dilution or dialysis approaches for suppressing protein aggregation is very important in the industrial field. In this paper, a modeling approach is...
Microfluidic devices with gold thin film channels for chemical and biomedical applications: a review, Article Biomedical Microdevices ; Volume 21, Issue 4 , 2019 ; 13872176 (ISSN) ; Rabiee, N ; Rabiee, M ; Bagherzadeh, M ; Tahriri, M ; Tayebi, L ; Hamblin, M. R ; Sharif University of Technology
Springer New York LLC 2019
Microfluidic systems (MFS) provide a range of advantages in biomedical applications, including improved controllability of material characteristics and lower consumption of reagents, energy, time and money. Fabrication of MFS employs various materials, such as glass, silicon, ceramics, paper, and metals such as gold, copper, aluminum, chromium and titanium. In this review, gold thin film microfluidic channels (GTFMFC) are discussed with reference to fabrication methods and their diverse use in chemical and biomedical applications. The advantages of gold thin films (GTF) include flexibility, ease of manufacture, adhesion to polymer surfaces, chemical stability, good electrical conductivity,...
Newtonian and generalized Newtonian reacting flows in serpentine microchannels: pressure driven and centrifugal microfluidics, Article Journal of Non-Newtonian Fluid Mechanics ; Volume 251 , January , 2018 , Pages 88-96 ; 03770257 (ISSN) ; Shamloo, A ; Sharif University of Technology
Elsevier B.V 2018
This paper presents a comprehensive 3D numerical simulation of reacting flows in micro scale dimension through centrifugal, or Lab-On-a-CD (LOCD), and pressure-driven, or Lab-On-a-Chip (LOC) devices. Three different serpentine channel configurations (rectangular, triangular and sinusoidal) are investigated. In these configurations, two chemical species enter from two inlets and according to an irreversible chemical reaction, start yielding other species. Both Newtonian and generalized Newtonian fluids are considered in the simulations and the results are compared for both LOC and LOCD devices. Besides, the effects of different parameters such as the aspect ratio of channels’ cross section,...
A tool for designing tree-like concentration gradient generators for lab-on-a-chip applications, Article Chemical Engineering Science ; Volume 212 , 2020 ; 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...
Microfluidic-based approaches in targeted cell/particle separation based on physical properties: fundamentals and applications, Article Small ; Volume 16, Issue 29 , 2020 ; Shamloo, A ; Ahadian, S ; Amirifar, L ; Akbari, J ; Goudie, M. J ; Lee, K ; Ashammakhi, N ; Dokmeci, M. R ; Di Carlo, D ; Khademhosseini, A ; Sharif University of Technology
Wiley-VCH Verlag 2020
Cell separation is a key step in many biomedical research areas including biotechnology, cancer research, regenerative medicine, and drug discovery. While conventional cell sorting approaches have led to high-efficiency sorting by exploiting the cell's specific properties, microfluidics has shown great promise in cell separation by exploiting different physical principles and using different properties of the cells. In particular, label-free cell separation techniques are highly recommended to minimize cell damage and avoid costly and labor-intensive steps of labeling molecular signatures of cells. In general, microfluidic-based cell sorting approaches can separate cells using “intrinsic”...
Deriving an analytical model for hydro-magnetic micro flow controller, Article 6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008, Darmstadt, 23 June 2008 through 25 June 2008 ; Issue PART B , June , 2008 , Pages 1139-1146 ; 0791848345 (ISBN); 9780791848340 (ISBN) ; Shafii, M. B ; ASME ; Sharif University of Technology
Fluid control, namely pumping and valving, is a critical factor in the performance of micro-fluidic systems. In recent years a variety of micro-fluidic systems are developed for the purpose of miniaturizing fluid handling, and chemical analysis to develop Lab On a Chip (LOC) technology. The mentioned facts resulted in design and fabrication of a novel hydromagnetic flow controller. The idea behind this device is that magnetic particles, mixed and dispersed in a carrier liquid, can be accumulated in the form of a piston. Depending upon dragging speed of these pistons, which itself is a function of switching time, this device can be used to either increase (pumping) or decrease (valving) the...
Emerging phospholipid nanobiomaterials for biomedical applications to lab-on-a-chip, drug delivery, and cellular engineering, Article ACS Applied Bio Materials ; 2021 ; 25766422 (ISSN) ; Rabiee, N ; Ahmadi, S ; Jahangiri, S ; Sajadi, S. M ; Akhavan, O ; Saeb, M. R ; Kwon, W ; Kim, M ; Hahn, S. K ; Sharif University of Technology
American Chemical Society 2021
The design of advanced nanobiomaterials to improve analytical accuracy and therapeutic efficacy has become an important prerequisite for the development of innovative nanomedicines. Recently, phospholipid nanobiomaterials including 2-methacryloyloxyethyl phosphorylcholine (MPC) have attracted great attention with remarkable characteristics such as resistance to nonspecific protein adsorption and cell adhesion for various biomedical applications. Despite many recent reports, there is a lack of comprehensive review on the phospholipid nanobiomaterials from synthesis to diagnostic and therapeutic applications. Here, we review the synthesis and characterization of phospholipid nanobiomaterials...
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
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...
A foreign body response-on-a-chip platform, Article Advanced Healthcare Materials ; Volume 8, Issue 4 , 2019 ; 21922640 (ISSN) ; Htwe, S. S ; Righi, M ; Liu, H ; Pietralunga, A ; Yesil Celiktas, O ; Maharjan, S ; Cha, B. H ; Shin, S. R ; Dokmeci, M. R ; Vrana, N. E ; Ghaemmaghami, A. M ; Khademhosseini, A ; Zhang, Y. S ; Sharif University of Technology
Wiley-VCH Verlag 2019
Understanding the foreign body response (FBR) and desiging strategies to modulate such a response represent a grand challenge for implant devices and biomaterials. Here, the development of a microfluidic platform is reported, i.e., the FBR-on-a-chip (FBROC) for modeling the cascade of events during immune cell response to implants. The platform models the native implant microenvironment where the implants are interfaced directly with surrounding tissues, as well as vasculature with circulating immune cells. The study demonstrates that the release of cytokines such as monocyte chemoattractant protein 1 (MCP-1) from the extracellular matrix (ECM)-like hydrogels in the bottom tissue chamber...