Current Search:  Microfluidic devices (x)

View All Items

  • CSV Spreadsheet
(1 - 9 of 9)
AQUEOUS MICRODROPLET GENERATION IN OIL-FREE ENVIRONMENTS
Title
AQUEOUS MICRODROPLET GENERATION IN OIL-FREE ENVIRONMENTS.
Creator
Mastiani, Mohammad, Kim, Myeongsub, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
Droplet microfluidics generates and manipulates microdroplets in microfluidic devices at high manufacturing efficiency and controllability. Microdroplets have proven effective in biomedical applications such as single-cell analysis, DNA sequencing, protein partitioning and drug delivery. Conventionally, a series of aqueous microdroplets containing biosamples is generated and controlled in an oil environment. One of the critical challenges in this system is that recovery of the aqueous samples...
Show moreDroplet microfluidics generates and manipulates microdroplets in microfluidic devices at high manufacturing efficiency and controllability. Microdroplets have proven effective in biomedical applications such as single-cell analysis, DNA sequencing, protein partitioning and drug delivery. Conventionally, a series of aqueous microdroplets containing biosamples is generated and controlled in an oil environment. One of the critical challenges in this system is that recovery of the aqueous samples from the oil phase is very difficult and often requires expensive and cumbersome post-processing. Also, the low Reynolds (Re) number characteristic of this system results in low throughput of droplet generation. To circumvent challenges and fully utilize microdroplets for practical clinical applications, this research aims to unpack the fundamental physics that governs droplet generation in oil-free systems including an aqueous two-phase system (ATPS) and a high inertial liquid-gas system.
Show less
Date Issued
2019
PURL
http://purl.flvc.org/fau/fd/FA00013332
Subject Headings
Microdroplets, Microfluidics, Microfluidic devices, Microfluidics--methods
Format
Document (PDF)
NOVEL RHEOTAXIS-BASED MICROFLUIDIC DEVICES FOR SORTING HUMAN SPERM
Title
NOVEL RHEOTAXIS-BASED MICROFLUIDIC DEVICES FOR SORTING HUMAN SPERM.
Creator
Ataei, Afrouz, Lau, Andy W.C., Florida Atlantic University, Department of Physics, Charles E. Schmidt College of Science
Abstract/Description
The ultimate challenge for assisted reproductive technologies (ARTs) is to select the most competent sperm population from a semen sample in an efficient way. In this thesis, we report on an effective sperm sorting microfluidic device that exploits the rheotaxis of sperm and investigates the sperm quality sorted under various flow conditions. Rheotaxis is the ability of a sperm cell to orient itself in the direction of the flow and swim against it. We developed a novel passively driven...
Show moreThe ultimate challenge for assisted reproductive technologies (ARTs) is to select the most competent sperm population from a semen sample in an efficient way. In this thesis, we report on an effective sperm sorting microfluidic device that exploits the rheotaxis of sperm and investigates the sperm quality sorted under various flow conditions. Rheotaxis is the ability of a sperm cell to orient itself in the direction of the flow and swim against it. We developed a novel passively driven pumping system that provides a steady flow rate while it requires no external power source. We have also developed another rheotaxis-based microfluidic device that washes out the raw semen sample from any dead or less motile sperm. The device consists of a collection and waste chamber. To evaluate the effect of the shape and height of the collection chamber, we measured the sperm motility and velocity parameters after sorting using varying the shape and height of the collection chamber. We demonstrated that sperm selected with all devices have higher motility, normal morphology, and a fewer degree of DNA fragmentation compared to a control group.
Show less
Date Issued
2022
PURL
http://purl.flvc.org/fau/fd/FA00013971
Subject Headings
Microfluidic devices, Rheotaxis, Spermatozoa, Reproductive Techniques, Assisted
Format
Document (PDF)
Automated control of microfluidics devices
Title
Automated control of microfluidics devices.
Creator
Gerstel, Ian., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
In order for microfluidics devices to be marketable, they must be inexpensive and easy to use. Two projects were pursued in this study for this purpose. The first was the design of a chip alignment system for visual feedback, in which a two-layer microfluidic chip was placed under a camera and an image processing and linear algebra program aligned a computer model to it. The system then translated the new locations of air valves and could detect valve activation in a chip filled with food...
Show moreIn order for microfluidics devices to be marketable, they must be inexpensive and easy to use. Two projects were pursued in this study for this purpose. The first was the design of a chip alignment system for visual feedback, in which a two-layer microfluidic chip was placed under a camera and an image processing and linear algebra program aligned a computer model to it. The system then translated the new locations of air valves and could detect valve activation in a chip filled with food coloring. The second was the design of a cheap, portable system to detect phosphorus in water. This system could not be completed due to time constraints, but the methods were detailed, and design ideas were laid out for future work.
Show less
Date Issued
2010
PURL
http://purl.flvc.org/FAU/3158764
Subject Headings
Microfluidics, Design, Microelectromagnetical systems, Design, Fluidic devices, Design, Micromechanics
Format
Document (PDF)
Design of micromixer and microfludic control system
Title
Design of micromixer and microfludic control system.
Creator
Li, Lin, Tsai, Chi-Tay, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
Micromixer is one of the most significant components of microfluidic systems, which manifest essential applications in the field of chemistry and biochemistry. Achieving complete mixing performance at the shortest micro channel length is essential for a successful micromixer design. We have developed five novel micromixers which have advantages of high efficiency, simple fabrication, easy integration and ease for mass production. The design principle is based on the concept of splitting...
Show moreMicromixer is one of the most significant components of microfluidic systems, which manifest essential applications in the field of chemistry and biochemistry. Achieving complete mixing performance at the shortest micro channel length is essential for a successful micromixer design. We have developed five novel micromixers which have advantages of high efficiency, simple fabrication, easy integration and ease for mass production. The design principle is based on the concept of splitting-recombination and chaotic advection. Numerical models of these micromixers are developed to characterize the mixing performance. Experiments are also carried out to fabricate the micromixers and evaluate the mixing performance. Numerical simulation for different parameters such as fluids properties, inlet velocities and microchannel cross sectional sizes are also conducted to investigate their effects on the mixing performance. The results show that critical inlet velocities can be predicted for normal fluid flow in the micromixers. When the inlet velocity is smaller than the critical value, the fluids mixing is dominated by mechanism of splitting-recombination, otherwise, it is dominated by chaotic advection. If the micromixer can tolerate higher inlet velocity, the complete mixing length can be further reduced. Our simulation results will provide valuable information for engineers to design a micromixer by choosing appropriate geometry to boost mixing performance and broaden implicational range to fit their specific needs. Accurate and complicated fluidic control, such as flow mixing or reaction, solution preparation, large scale combination of different reagents is also important for bio-application of microfluidics. A proposal microfluidic system is capable of creating 1024 kinds of combination mixtures. The system is composed of a high density integrated microfluidic chip and control system. The high density microfluidic chip, which is simply fabricated through soft lithography technique, contains a pair of 32 flow channels that can be specifically addressed by each 10 actuation channels based on principle of multiplexor in electronic circuits. The corresponding hardware and software compose the control system, which can be easy fabricated and modified, especially for prototype machine developing. Moreover, the control system has general application. Experiments are conducted to verify the feasibility of this microfluidic system for multi-optional solution combination.
Show less
Date Issued
2013
PURL
http://purl.flvc.org/fau/fd/FA0004033
Subject Headings
Flow visualization, Fluidic devices -- Design, Microelectromagnetical systems, Microfluidics -- Design
Format
Document (PDF)
DEVELOPMENT OF POINT-OF-CARE ASSAYS FOR ZIKA VIRUS DIAGNOSTIC
Title
DEVELOPMENT OF POINT-OF-CARE ASSAYS FOR ZIKA VIRUS DIAGNOSTIC.
Creator
Md Alamgir Kabir, Asghar, Waseem, Florida Atlantic University, Department of Computer and Electrical Engineering and Computer Science, College of Engineering and Computer Science
Abstract/Description
Zika virus (ZIKV) is an emerging flavivirus transmitted to humans by Aedes mosquitos. ZIKV can be transmitted from mother to fetus during pregnancy and can cause microcephaly and other birth defects. Effective vaccines for Zika are yet to be approved. Detection of the ZIKV is based on serological testing that often shows cross-reactivity with the Dengue virus (DENV) and other flaviviruses. Currently, identification of ZIKV infection is usually done by i) testing the patient’s serum sample to...
Show moreZika virus (ZIKV) is an emerging flavivirus transmitted to humans by Aedes mosquitos. ZIKV can be transmitted from mother to fetus during pregnancy and can cause microcephaly and other birth defects. Effective vaccines for Zika are yet to be approved. Detection of the ZIKV is based on serological testing that often shows cross-reactivity with the Dengue virus (DENV) and other flaviviruses. Currently, identification of ZIKV infection is usually done by i) testing the patient’s serum sample to detect ZIKV RNA using reverse transcriptase-polymerase chain reaction (RT-PCR), ii) testing patient’s serum sample for the presence of the NS1 protein antigen or iii) serological assays to determine the presence of virus-specific immunoglobin antibodies (IgG and IgM) by the use of ELISA assay. But ELISA-based assays show cross-reactivity and poor sensitivity. The gold standard for ZIKV RNA detection is RT-PCR, involves expensive medical facilities and skillful technicians. However, the plaque reduction neutralization test are executed to quantity neutralizing antibodies of the virus-but show high accuracy only after day 7 of the disease onset. Therefore, the development of POC assays which has the ASSURED (affordability, sensitivity, specificity, user-friendly, rapid and robust, equipment-free and deliverable) criteria defined by the World Health Organization are topmost priority. The core objective of this thesis is to find inexpensive, sensitive, precise, and fast assays for the specific diagnosis of ZIKV suitable for resource-constrained settings.
Show less
Date Issued
2021
PURL
http://purl.flvc.org/fau/fd/FA00013836
Subject Headings
Point-of-care testing, Zika virus, Microfluidic devices
Format
Document (PDF)
DEVELOPMENT OF A MICROFLUIDIC DEVICE FOR EXOSOME ISOLATION IN POINT-OF-CARE SETTINGS
Title
DEVELOPMENT OF A MICROFLUIDIC DEVICE FOR EXOSOME ISOLATION IN POINT-OF-CARE SETTINGS.
Creator
Ramnauth, Natasha, Waseem Asghar, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
Exosomes have gained recognition in cancer diagnostics and therapeutics. Most exosome isolation methods are time-consuming, costly and require bulky equipment, rendering them unsuitable for point-of-care (POC) settings. Microfluidics can be the key to solving these challenges. Here, we employ the development of a double filtration microfluidic device that can rapidly isolate exosomes in POC settings. The device can efficiently isolate exosomes from just 100 uL of plasma within 50 minutes. The...
Show moreExosomes have gained recognition in cancer diagnostics and therapeutics. Most exosome isolation methods are time-consuming, costly and require bulky equipment, rendering them unsuitable for point-of-care (POC) settings. Microfluidics can be the key to solving these challenges. Here, we employ the development of a double filtration microfluidic device that can rapidly isolate exosomes in POC settings. The device can efficiently isolate exosomes from just 100 uL of plasma within 50 minutes. The device was compared against Polyethylene glycol (PEG) based precipitation, and findings show that both methods yield comparable exosome sizes and purity, but the device can detect exosomal miRNA earlier than PEG. Finally, a comparative analysis of membrane filters with exosomes collected from pore sizes 15 nm and 30 nm showed a similarity in exosome size and miRNA expressions, with significantly increased sample purity. These findings suggest that this device has potential in POC settings.
Show less
Date Issued
2022
PURL
http://purl.flvc.org/fau/fd/FA00014071
Subject Headings
Microfluidic devices, Exosomes, Point-of-care testing
Format
Document (PDF)
DEVELOPMENT OF POINT-OF-CARE ASSAYS FOR DISEASE DIAGNOSTIC AND TREATMENT MONITORING FOR RESOURCE CONSTRAINED SETTINGS
Title
DEVELOPMENT OF POINT-OF-CARE ASSAYS FOR DISEASE DIAGNOSTIC AND TREATMENT MONITORING FOR RESOURCE CONSTRAINED SETTINGS.
Creator
Sher, Mazhar, Asghar, Waseem, Florida Atlantic University, Department of Computer and Electrical Engineering and Computer Science, College of Engineering and Computer Science
Abstract/Description
This thesis aims to address the challenges of the development of cost-effective and rapid assays for the accurate counting of CD4+ T cells and quantification of HIV-1 viral load for resource-constrained settings. The lack of such assays has severely affected people living in disease prevalent areas. CD4+ T cells count information plays a vital role in the effective management of HIV-1 disease. Here, we present a flow-free magnetic actuation platform that uses antibody-coated magnetic beads to...
Show moreThis thesis aims to address the challenges of the development of cost-effective and rapid assays for the accurate counting of CD4+ T cells and quantification of HIV-1 viral load for resource-constrained settings. The lack of such assays has severely affected people living in disease prevalent areas. CD4+ T cells count information plays a vital role in the effective management of HIV-1 disease. Here, we present a flow-free magnetic actuation platform that uses antibody-coated magnetic beads to efficiently capture CD4+ T cells from a 30 μL drop of whole blood. On-chip cell lysate electrical impedance spectroscopy has been utilized to quantify the isolated CD4 cells. The developed assay has a limit of detection of 25 cells per μL and provides accurate CD4 counts in the range of 25–800 cells per μL. The whole immunoassay along with the enumeration process is very rapid and provides CD4 quantification results within 5 min time frame. The assay does not require off-chip sample preparation steps and minimizes human involvement to a greater extent. The developed impedance-based immunoassay has the potential to significantly improve the CD4 enumeration process especially for POC settings.
Show less
Date Issued
2020
PURL
http://purl.flvc.org/fau/fd/FA00013495
Subject Headings
Point-of-care testing, Diagnostic tests, Immunoassay, HIV-1, Microfluidic devices
Format
Document (PDF)
MULTIPHYSICS SIMULATION OF DIELECTROPHORESIS ENRICHMENT FOR DETECTION OF LOW PARASITEMIA PLASMODIUM FALCIPARUM IN HUMAN BLOOD
Title
MULTIPHYSICS SIMULATION OF DIELECTROPHORESIS ENRICHMENT FOR DETECTION OF LOW PARASITEMIA PLASMODIUM FALCIPARUM IN HUMAN BLOOD.
Creator
Oladokun, Oladiran, Du, E., Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description
Malaria is an ancient lethargic disease that remains a global burden. It has been difficult to end the scourge of P. falciparum malaria because of the parasites’ drug resistance so early diagnosis of malaria is crucial. Microscopy remains the gold standard but has limited reliability in detecting malaria parasites. This study proffered a method towards detection of low parasitemia P. falciparum infected RBCs (Pf-RBCs) based on dielectrophoresis (DEP). A microfluidic device was designed for...
Show moreMalaria is an ancient lethargic disease that remains a global burden. It has been difficult to end the scourge of P. falciparum malaria because of the parasites’ drug resistance so early diagnosis of malaria is crucial. Microscopy remains the gold standard but has limited reliability in detecting malaria parasites. This study proffered a method towards detection of low parasitemia P. falciparum infected RBCs (Pf-RBCs) based on dielectrophoresis (DEP). A microfluidic device was designed for label-free cell sorting of Pf-RBCs from other whole blood in a continuous manner, based on the intrinsic electrical signatures of the cells. The design was validated by a finite element simulation using COMSOL Multiphysics. Simulations show the feasibility of the separation in a 9-mm long microfluidic channel under laminar flow conditions, using a low voltage supply of +/-10 V at 50 kHz.
Show less
Date Issued
2024
PURL
http://purl.flvc.org/fau/fd/FA00014415
Subject Headings
Plasmodium falciparum, Microfluidic devices, Dielectrophoresis, Biomedical engineering, Point-of-care testing
Format
Document (PDF)
Recovering Titanium Dioxide (TiO2) after its Use to Treat Leachate for Reuse on Future Leachate Flows
Title
Recovering Titanium Dioxide (TiO2) after its Use to Treat Leachate for Reuse on Future Leachate Flows.
Creator
Coffman, Neil, Meeroff, Daniel E., Florida Atlantic University, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description
This thesis was about finding a recovery method for TiO2, using a TiO2 recovery technology, which was high enough to be economical ($10 - $15 per 1,000 gallons) to be adopted by wastewater treatment plants. When comparing recovery technologies, the top three which were investigated further through experimentation were a centrifuge, sedimentation tank, and microfilter membrane. Upon experimentation and research, the TiO2 recovery efficiencies of these technologies were 99.5%, 92.5%, and 96.3%,...
Show moreThis thesis was about finding a recovery method for TiO2, using a TiO2 recovery technology, which was high enough to be economical ($10 - $15 per 1,000 gallons) to be adopted by wastewater treatment plants. When comparing recovery technologies, the top three which were investigated further through experimentation were a centrifuge, sedimentation tank, and microfilter membrane. Upon experimentation and research, the TiO2 recovery efficiencies of these technologies were 99.5%, 92.5%, and 96.3%, respectively. When doing economic analysis on these technologies comparing TiO2 efficiencies and capital and operational costs, the centrifuge was the most preferred economic option. Also, its cost did were in the economical range ($10 - $15/1,000 gallons) which makes even this technology economical. Besides that, important and valuable information about TiO2: settling behavior, particle size and zeta potential, interactions with COD, and filter operations (particle characterization) were discovered for future research and future testing on this issue.
Show less
Date Issued
2015
PURL
http://purl.flvc.org/fau/fd/FA00004490, http://purl.flvc.org/fau/fd/FA00004490
Subject Headings
Environmental chemistry, Environmental engineering, Fluid dynamics, Microfluidic devices, Sewage disposal plants -- Management, Solution (Chemistry), Titanium dioxide -- Environmental aspects, Titanium dioxide -- Industrial applications
Format
Document (PDF)