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Sample records for blood diagnostic microfluidic

  1. A novel passive microfluidic device for preprocessing whole blood for point of care diagnostics

    DEFF Research Database (Denmark)

    Shah, Pranjul Jaykumar; Dimaki, Maria; Svendsen, Winnie Edith

    2009-01-01

    A novel strategy to sort the cells of interest (White Blood Cells (leukocytes)) by selectively lysing the Red Blood Cells (erythrocytes) in a miniaturized microfluidic device is presented. Various methods to lyse cells on a chip exist i.e. electrical, mechanical, chemical and thermal but they need...... on the principle of mixing whole blood with pure water in time controlled manner to lyse erythrocytes osmotically on a chip....

  2. Applications of Microfluidics for Molecular Diagnostics

    OpenAIRE

    Jayamohan, Harikrishnan; Sant, Himanshu J.; Bruce K. Gale

    2012-01-01

    Diagnostic assays implemented in microfluidic devices have developed rapidly over the past decade and are expected to become commonplace in the next few years. Hundreds of microfluidics-based approaches towards clinical diagnostics and pathogen detection have been reported with a general theme of rapid and customizable assays that are potentially cost-effective. This chapter reviews microfluidics in molecular diagnostics based on application areas with a concise review of microfluidics in gen...

  3. Integrating plasmonic diagnostics and microfluidics.

    Science.gov (United States)

    Niu, Lifang; Zhang, Nan; Liu, Hong; Zhou, Xiaodong; Knoll, Wolfgang

    2015-09-01

    Plasmonics is generally divided into two categories: surface plasmon resonance (SPR) of electromagnetic modes propagating along a (noble) metal/dielectric interface and localized SPRs (LSPRs) on nanoscopic metallic structures (particles, rods, shells, holes, etc.). Both optical transducer concepts can be combined with and integrated in microfluidic devices for biomolecular analyte detections, with the benefits of small foot-print for point-of-care detection, low-cost for one-time disposal, and ease of being integrated into an array format. The key technologies in such integration include the plasmonic chip, microfluidic channel fabrication, surface bio-functionalization, and selection of the detection scheme, which are selected according to the specifics of the targeting analytes. This paper demonstrates a few examples of the many versions of how to combine plasmonics and integrated microfluidics, using different plasmonic generation mechanisms for different analyte detections. One example is a DNA sensor array using a gold film as substrate and surface plasmon fluorescence spectroscopy and microscopy as the transduction method. This is then compared to grating-coupled SPR for poly(ethylene glycol) thiol interaction detected by angle interrogation, gold nanohole based LSPR chip for biotin-strepavidin detection by wavelength shift, and gold nanoholes/nanopillars for the detection of prostate specific antigen by quantum dot labels excited by the LSPR. Our experimental results exemplified that the plasmonic integrated microfluidics is a promising tool for understanding the biomolecular interactions and molecular recognition process as well as biosensing, especially for on-site or point-of-care diagnostics. PMID:26392832

  4. Microfluidic Devices for Blood Fractionation

    Directory of Open Access Journals (Sweden)

    Chwee Teck Lim

    2011-07-01

    Full Text Available Blood, a complex biological fluid, comprises 45% cellular components suspended in protein rich plasma. These different hematologic components perform distinct functions in vivo and thus the ability to efficiently fractionate blood into its individual components has innumerable applications in both clinical diagnosis and biological research. Yet, processing blood is not trivial. In the past decade, a flurry of new microfluidic based technologies has emerged to address this compelling problem. Microfluidics is an attractive solution for this application leveraging its numerous advantages to process clinical blood samples. This paper reviews the various microfluidic approaches realized to successfully fractionate one or more blood components. Techniques to separate plasma from hematologic cellular components as well as isolating blood cells of interest including certain rare cells are discussed. Comparisons based on common separation metrics including efficiency (sensitivity, purity (selectivity, and throughput will be presented. Finally, we will provide insights into the challenges associated with blood-based separation systems towards realizing true point-of-care (POC devices and provide future perspectives.

  5. Handheld Microfluidic Blood Ananlyzer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Nanohmics proposes to develop a handheld blood analyzer for micro- and hypo-gravity missions. The prototype instrument will combine impedance analysis with optical...

  6. Droplet Microfluidics for Chip-Based Diagnostics

    Directory of Open Access Journals (Sweden)

    Karan V. I. S. Kaler

    2014-12-01

    Full Text Available Droplet microfluidics (DMF is a fluidic handling technology that enables precision control over dispensing and subsequent manipulation of droplets in the volume range of microliters to picoliters, on a micro-fabricated device. There are several different droplet actuation methods, all of which can generate external stimuli, to either actively or passively control the shape and positioning of fluidic droplets over patterned substrates. In this review article, we focus on the operation and utility of electro-actuation-based DMF devices, which utilize one or more micro-/nano-patterned substrates to facilitate electric field-based handling of chemical and/or biological samples. The underlying theory of DMF actuations, device fabrication methods and integration of optical and opto-electronic detectors is discussed in this review. Example applications of such electro-actuation-based DMF devices have also been included, illustrating the various actuation methods and their utility in conducting chip-based laboratory and clinical diagnostic assays.

  7. Microfluidic Cytometer for Complete Blood Count Analysis Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We will fabricate and test microfluidic designs for a micro-electromechanical system based complete blood count (CBC) analysis in separate modules and integrate...

  8. Microfluidic Cytometer for Complete Blood Count Analysis Project

    Data.gov (United States)

    National Aeronautics and Space Administration — RMD proposes to develop a MEMS based complete blood count (CBC) instrument that can be used aboard a spacecraft. We will produce a microfluidic scale combination...

  9. Particles and microfluidics merged: Perspectives of highly sensitive diagnostic detection

    International Nuclear Information System (INIS)

    There is a growing need for diagnostic technologies that provide laboratories with solutions that improve quality, enhance laboratory system productivity, and provide accurate detection of a broad range of infectious diseases and cancers. Recent advances in micro- and nanoscience and engineering, in particular in the areas of particles and microfluidic technologies, have advanced the 'lab-on-a-chip' concept towards the development of a new generation of point-of-care diagnostic devices that could significantly enhance test sensitivity and speed. In this review, we will discuss many of the recent advances in microfluidics and particle technologies with an eye towards merging these two technologies for application in medical diagnostics. Although the potential diagnostic applications are virtually unlimited, the most important applications are foreseen in the areas of biomarker research, cancer diagnosis, and detection of infectious microorganisms. (author)

  10. Antigen-Responsive, Microfluidic Valves for Single Use Diagnostics

    Science.gov (United States)

    Berron, Brad J.; May, Allison M.; Zheng, Zheng; Balasubramaniam, Vivek

    2014-01-01

    The growing need for medical diagnostics in resource limited settings is driving the development of simple, standalone immunoassay devices. A capillary flow device using polymerization based amplification is capable of blocking a microfluidic channel in response to target biomaterials, enabling multiple modes of detection that require little or no supplemental instrumentation. PMID:22218407

  11. Antigen-Responsive, Microfluidic Valves for Single Use Diagnostics

    OpenAIRE

    Berron, Brad J.; May, Allison M.; Zheng, Zheng; Balasubramaniam, Vivek; Bowman, Christopher N.

    2012-01-01

    The growing need for medical diagnostics in resource limited settings is driving the development of simple, standalone immunoassay devices. A capillary flow device using polymerization based amplification is capable of blocking a microfluidic channel in response to target biomaterials, enabling multiple modes of detection that require little or no supplemental instrumentation.

  12. A simple microfluidic device for the deformability assessment of blood cells in a continuous flow.

    Science.gov (United States)

    Rodrigues, Raquel O; Pinho, Diana; Faustino, Vera; Lima, Rui

    2015-12-01

    Blood flow presents several interesting phenomena in microcirculation that can be used to develop microfluidic devices capable to promote blood cells separation and analysis in continuous flow. In the last decade there have been numerous microfluidic studies focused on the deformation of red blood cells (RBCs) flowing through geometries mimicking microvessels. In contrast, studies focusing on the deformation of white blood cells (WBCs) are scarce despite this phenomenon often happens in the microcirculation. In this work, we present a novel integrative microfluidic device able to perform continuous separation of a desired amount of blood cells, without clogging or jamming, and at the same time, capable to assess the deformation index (DI) of both WBCs and RBCs. To determine the DI of both WBCs and RBCs, a hyperbolic converging microchannel was used, as well as a suitable image analysis technique to measure the DIs of these blood cells along the regions of interest. The results show that the WBCs have a much lower deformability than RBCs when subjected to the same in vitro flow conditions, which is directly related to their cytoskeleton and nucleus contents. The proposed strategy can be easily transformed into a simple and inexpensive diagnostic microfluidic system to simultaneously separate and assess blood cells deformability. PMID:26482154

  13. Microfluidic platform for separation and extraction of plasma from whole blood using dielectrophoresis.

    Science.gov (United States)

    Szydzik, Crispin; Khoshmanesh, Khashayar; Mitchell, Arnan; Karnutsch, Christian

    2015-11-01

    Microfluidic based blood plasma extraction is a fundamental necessity that will facilitate many future lab-on-a-chip based point-of-care diagnostic systems. However, current approaches for providing this analyte are hampered by the requirement to provide external pumping or dilution of blood, which result in low effective yield, lower concentration of target constituents, and complicated functionality. This paper presents a capillary-driven, dielectrophoresis-enabled microfluidic system capable of separating and extracting cell-free plasma from small amounts of whole human blood. This process takes place directly on-chip, and without the requirement of dilution, thus eliminating the prerequisite of pre-processed blood samples and external liquid handling systems. The microfluidic chip takes advantage of a capillary pump for driving whole blood through the main channel and a cross flow filtration system for extracting plasma from whole blood. This filter is actively unblocked through negative dielectrophoresis forces, dramatically enhancing the volume of extracted plasma. Experiments using whole human blood yield volumes of around 180 nl of cell-free, undiluted plasma. We believe that implementation of various integrated biosensing techniques into this plasma extraction system could enable multiplexed detection of various biomarkers. PMID:26759637

  14. Dynamics of blood flow in a microfluidic ladder network

    Science.gov (United States)

    Maddala, Jeevan; Zilberman-Rudenko, Jevgenia; McCarty, Owen

    The dynamics of a complex mixture of cells and proteins, such as blood, in perturbed shear flow remains ill-defined. Microfluidics is a promising technology for improving the understanding of blood flow under complex conditions of shear; as found in stent implants and in tortuous blood vessels. We model the fluid dynamics of blood flow in a microfluidic ladder network with dimensions mimicking venules. Interaction of blood cells was modeled using multiagent framework, where cells of different diameters were treated as spheres. This model served as the basis for predicting transition regions, collision pathways, re-circulation zones and residence times of cells dependent on their diameters and device architecture. Based on these insights from the model, we were able to predict the clot formation configurations at various locations in the device. These predictions were supported by the experiments using whole blood. To facilitate platelet aggregation, the devices were coated with fibrillar collagen and tissue factor. Blood was perfused through the microfluidic device for 9 min at a physiologically relevant venous shear rate of 600 s-1. Using fluorescent microscopy, we observed flow transitions near the channel intersections and at the areas of blood flow obstruction, which promoted larger thrombus formation. This study of integrating model predictions with experimental design, aids in defining the dynamics of blood flow in microvasculature and in development of novel biomedical devices.

  15. Microfluidic Sensing Platforms for Medicine and Diagnostics

    DEFF Research Database (Denmark)

    Kiilerich-Pedersen, Katrine

    for decentralized clinical applications in medicine and diagnostics. In this PhD project, low cost electrochemical plastic sensors for basic research, diagnosis of viral infections or drug discovery were developed and evaluated. In the developed biosensor chip, early signs of virus infection in cell culture could...... was adapted to selectively fish out virions from body fluid by aptamer functionalization. The intact virus particles were captured by immobilized aptamer probes on conductive polymer electrodes, allowing fast and easy electrical detection. The sensor responded rapidly, and showed high sensitivity...... the integration of electrical sensors into low cost plastic microdevices pioneering point of care testing. The presented biosensing platforms have potential for scaling up towards high throughput screening, and are adaptable to other applications in medicine and diagnostics, and other fields....

  16. Integrated separation of blood plasma from whole blood for microfluidic paper-based analytical devices.

    Science.gov (United States)

    Yang, Xiaoxi; Forouzan, Omid; Brown, Theodore P; Shevkoplyas, Sergey S

    2012-01-21

    Many diagnostic tests in a conventional clinical laboratory are performed on blood plasma because changes in its composition often reflect the current status of pathological processes throughout the body. Recently, a significant research effort has been invested into the development of microfluidic paper-based analytical devices (μPADs) implementing these conventional laboratory tests for point-of-care diagnostics in resource-limited settings. This paper describes the use of red blood cell (RBC) agglutination for separating plasma from finger-prick volumes of whole blood directly in paper, and demonstrates the utility of this approach by integrating plasma separation and a colorimetric assay in a single μPAD. The μPAD was fabricated by printing its pattern onto chromatography paper with a solid ink (wax) printer and melting the ink to create hydrophobic barriers spanning through the entire thickness of the paper substrate. The μPAD was functionalized by spotting agglutinating antibodies onto the plasma separation zone in the center and the reagents of the colorimetric assay onto the test readout zones on the periphery of the device. To operate the μPAD, a drop of whole blood was placed directly onto the plasma separation zone of the device. RBCs in the whole blood sample agglutinated and remained in the central zone, while separated plasma wicked through the paper substrate into the test readout zones where analyte in plasma reacted with the reagents of the colorimetric assay to produce a visible color change. The color change was digitized with a portable scanner and converted to concentration values using a calibration curve. The purity and yield of separated plasma was sufficient for successful operation of the μPAD. This approach to plasma separation based on RBC agglutination will be particularly useful for designing fully integrated μPADs operating directly on small samples of whole blood. PMID:22094609

  17. Microfluidic optoelectronic sensor for salivary diagnostics of stomach cancer.

    Science.gov (United States)

    Zilberman, Yael; Sonkusale, Sameer R

    2015-05-15

    We present a microfluidic optoelectronic sensor for saliva diagnostics with a potential application for non-invasive early diagnosis of stomach cancer. Stomach cancer is the second most common cause of cancer-related deaths in the world. The primary identified cause is infection by a gram-negative bacterium Helicobacter pylori. These bacteria secrete the enzyme urease that converts urea into carbon dioxide (CO2) and ammonia (NH3), leading to their elevated levels in breath and body fluids. The proposed optoelectronic sensor will detect clinically relevant levels of CO2 and NH3 in saliva that can potentially be used for early diagnosis of stomach cancer. The sensor is composed of the embedded in a microfluidic device array of microwells filled with ion-exchange polymer microbeads doped with various organic dyes. The optical response of this unique highly diverse sensor is monitored over a broad spectrum, which provides a platform for cross-reactive sensitivity and allows detection of CO2 and NH3 in saliva at ppm levels. PMID:25223554

  18. Hydrodynamic blood plasma separation in microfluidic channels

    DEFF Research Database (Denmark)

    Jouvet, Lionel

    2010-01-01

    The separation of red blood cells from plasma flowing in microchannels is possible by biophysical effects such as the Zweifach–Fung bifurcation law. In the present study, daughter channels are placed alongside a main channel such that cells and plasma are collected separately. The device is aimed...

  19. Product qualification: a barrier to point-of-care microfluidic-based diagnostics?

    Science.gov (United States)

    Tantra, Ratna; van Heeren, Henne

    2013-06-21

    One of the most exciting applications of microfluidics-based diagnostics is its potential use in next generation point-of-care (POC) devices. Many prototypes are already in existence, but, as of yet, few have achieved commercialisation. In this article, we consider the issue surrounding product qualification as a potential barrier to market success. The study discusses, in the context of POC microfluidics-based diagnostics, what the generic issues are and potential solutions. Our findings underline the need for a community-based effort that is necessary to speed up the product qualification process. PMID:23652789

  20. Electric tempest in a teacup: The tea leaf analogy to microfluidic blood plasma separation

    Science.gov (United States)

    Yeo, Leslie Y.; Friend, James R.; Arifin, Dian R.

    2006-09-01

    In a similar fashion to Einstein's tea leaf paradox, the rotational liquid flow induced by ionic wind above a liquid surface can trap suspended microparticles by a helical motion, spinning them down towards a bottom stagnation point. The motion is similar to Batchelor [Q. J. Mech. Appl. Math. 4, 29 (1951)] flows occurring between stationary and rotating disks and arises due to a combination of the primary azimuthal and secondary bulk meridional recirculation that produces a centrifugal and enhanced inward radial force near the chamber bottom. The technology is thus useful for microfluidic particle trapping/concentration; the authors demonstrate its potential for rapid erythrocyte/blood plasma separation for miniaturized medical diagnostic kits.

  1. Modular microfluidic cartridge-based universal diagnostic system for global health applications

    Science.gov (United States)

    Becker, Holger; Klemm, Richard; Dietze, William; White, Wallace; Hlawatsch, Nadine; Freyberg, Susanne; Moche, Christian; Dailey, Peter; Gärtner, Claudia

    2016-03-01

    Current microfluidics-enabled point-of-care diagnostic systems are typically designed specifically for one assay type, e.g. a molecular diagnostic assay for a single disease of a class of diseases. This approach often leads to high development cost and a significant training requirement for users of different instruments. We have developed an open platform diagnostic system which allows to run molecular, immunological and clinical assays on a single instrument platform with a standardized microfluidic cartridge architecture in an automated sample-in answer-out fashion. As examples, a molecular diagnostic assay for tuberculosis, an immunoassay for HIV p24 and a clinical chemistry assay for ALT liver function have been developed and results of their pre-clinical validation are presented.

  2. A micro-fluidic study of whole blood behaviour on PMMA topographical nanostructures

    Directory of Open Access Journals (Sweden)

    Tsud Nataliya

    2008-02-01

    Full Text Available Abstract Background Polymers are attractive materials for both biomedical engineering and cardiovascular applications. Although nano-topography has been found to influence cell behaviour, no established method exists to understand and evaluate the effects of nano-topography on polymer-blood interaction. Results We optimized a micro-fluidic set-up to study the interaction of whole blood with nano-structured polymer surfaces under flow conditions. Micro-fluidic chips were coated with polymethylmethacrylate films and structured by polymer demixing. Surface feature size varied from 40 nm to 400 nm and feature height from 5 nm to 50 nm. Whole blood flow rate through the micro-fluidic channels, platelet adhesion and von Willebrand factor and fibrinogen adsorption onto the structured polymer films were investigated. Whole blood flow rate through the micro-fluidic channels was found to decrease with increasing average surface feature size. Adhesion and spreading of platelets from whole blood and von Willebrand factor adsorption from platelet poor plasma were enhanced on the structured surfaces with larger feature, while fibrinogen adsorption followed the opposite trend. Conclusion We investigated whole blood behaviour and plasma protein adsorption on nano-structured polymer materials under flow conditions using a micro-fluidic set-up. We speculate that surface nano-topography of polymer films influences primarily plasma protein adsorption, which results in the control of platelet adhesion and thrombus formation.

  3. Microfluidic Flow Chambers Using Reconstituted Blood to Model Hemostasis and Platelet Transfusion In Vitro.

    Science.gov (United States)

    Van Aelst, Britt; Feys, Hendrik B; Devloo, Rosalie; Vandekerckhove, Philippe; Compernolle, Veerle

    2016-01-01

    Blood platelets prepared for transfusion gradually lose hemostatic function during storage. Platelet function can be investigated using a variety of (indirect) in vitro experiments, but none of these is as comprehensive as microfluidic flow chambers. In this protocol, the reconstitution of thrombocytopenic fresh blood with stored blood bank platelets is used to simulate platelet transfusion. Next, the reconstituted sample is perfused in microfluidic flow chambers which mimic hemostasis on exposed subendothelial matrix proteins. Effects of blood donation, transport, component separation, storage and pathogen inactivation can be measured in paired experimental designs. This allows reliable comparison of the impact every manipulation in blood component preparation has on hemostasis. Our results demonstrate the impact of temperature cycling, shear rates, platelet concentration and storage duration on platelet function. In conclusion, this protocol analyzes the function of blood bank platelets and this ultimately aids in optimization of the processing chain including phlebotomy, transport, component preparation, storage and transfusion. PMID:27023054

  4. Electrodiffusion Method of Near-Wall Flow Diagnostics in Microfluidic Systems.

    Czech Academy of Sciences Publication Activity Database

    Tihon, Jaroslav; Pěnkavová, Věra; Stanovský, Petr; Vejražka, Jiří

    Ozarow Mazowiecki : Nobell Compressing sp. z o.o, 2015 - (Kosinsky, K.; Urbanczyk, M.; Žerko, S.), s. 89 ISBN N. [Smart and Green Interfaces Conference - SGIC2015. Belgrade (RS), 30.03.2015-01.04.2015] R&D Projects: GA MŠk(CZ) LD13018 Institutional support: RVO:67985858 Keywords : electrodiffusion method * flow diagnostics * microfluidics Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  5. Performance enhanced UV/vis spectroscopic microfluidic sensor for ascorbic acid quantification in human blood.

    Science.gov (United States)

    Bi, Hongyan; Duarte, Carla M; Brito, Marina; Vilas-Boas, Vânia; Cardoso, Susana; Freitas, Paulo

    2016-11-15

    Quantitative analysis of antioxidants in a fast, simple and accurate manner is of great importance in the view of real-time monitoring the health of individuals. Recently, we have developed a UV/vis spectroscopic microfluidic sensor to specifically quantify ascorbic acid based on the immobilization of ascorbate oxidase, a relatively unstable enzyme. In this work, three different strategies for the immobilization of the unstable enzyme, including alumina sol-gel encapsulation, physisorption to PDMS channels with, and without alumina xerogel modification, were compared to build a microsensor. We found that the loading amount of the enzyme is not the determinative factor for the performance of the microfluidic biosensor but the retained activity of the enzyme and diffusion in the microfluidic channel. Taking into account of the two factors, the protocol of adsorbing enzymes to alumina (Al2O3) xerogel modified PDMS surface was demonstrated to be the best for preparing the microfluidic sensor among the utilized protocols. The microsensor prepared under the optimized protocol was further used to quantify ascorbic acid in human blood, where only dozens of microliters of blood (few drops) was required, demonstrating its potential application in clinical diagnosis. The developed strategy is featured with optimized enzymatic activity, simple process of microfluidic platform, low sample consumption, and straightforward spectrophotometry based detection. PMID:27236140

  6. Microfluidic point-of-care blood panel based on a novel technique: Reversible electroosmotic flow.

    Science.gov (United States)

    Mohammadi, Mahdi; Madadi, Hojjat; Casals-Terré, Jasmina

    2015-09-01

    A wide range of diseases and conditions are monitored or diagnosed from blood plasma, but the ability to analyze a whole blood sample with the requirements for a point-of-care device, such as robustness, user-friendliness, and simple handling, remains unmet. Microfluidics technology offers the possibility not only to work fresh thumb-pricked whole blood but also to maximize the amount of the obtained plasma from the initial sample and therefore the possibility to implement multiple tests in a single cartridge. The microfluidic design presented in this paper is a combination of cross-flow filtration with a reversible electroosmotic flow that prevents clogging at the filter entrance and maximizes the amount of separated plasma. The main advantage of this design is its efficiency, since from a small amount of sample (a single droplet [Formula: see text]10 μl) almost 10% of this (approx 1 μl) is extracted and collected with high purity (more than 99%) in a reasonable time (5-8 min). To validate the quality and quantity of the separated plasma and to show its potential as a clinical tool, the microfluidic chip has been combined with lateral flow immunochromatography technology to perform a qualitative detection of the thyroid-stimulating hormone and a blood panel for measuring cardiac Troponin and Creatine Kinase MB. The results from the microfluidic system are comparable to previous commercial lateral flow assays that required more sample for implementing fewer tests. PMID:26396660

  7. Refined Method for Droplet Microfluidics-Enabled Detection of Plasmodium falciparum Encoded Topoisomerase I in Blood from Malaria Patients

    Directory of Open Access Journals (Sweden)

    Marianne Smedegaard Hede

    2015-10-01

    Full Text Available Rapid and reliable diagnosis is essential in the fight against malaria, which remains one of the most deadly infectious diseases in the world. In the present study we take advantage of a droplet microfluidics platform combined with a novel and user-friendly biosensor for revealing the main malaria-causing agent, the Plasmodium falciparum (P. falciparum parasite. Detection of the parasite is achieved through detection of the activity of a parasite-produced DNA-modifying enzyme, topoisomerase I (pfTopoI, in the blood from malaria patients. The assay presented has three steps: (1 droplet microfluidics-enabled extraction of active pfTopoI from a patient blood sample; (2 pfTopoI-mediated modification of a specialized DNA biosensor; (3 readout. The setup is quantitative and specific for the detection of Plasmodium topoisomerase I. The procedure is a considerable improvement of the previously published Rolling Circle Enhanced Enzyme Activity Detection (REEAD due to the advantages of involving no signal amplification steps combined with a user-friendly readout. In combination these alterations represent an important step towards exploiting enzyme activity detection in point-of-care diagnostics of malaria.

  8. Manufacturing routes for disposable polymer blood diagnostic microfluidic systems

    DEFF Research Database (Denmark)

    Tosello, Guido; Griffiths, Christian; Azcarate, Sabino;

    2008-01-01

    (Multi-Material Micro Manufacture) that are relevant to the technology for disposable polymer parts for Micro-Tele-BioChip (µTBC) medical platforms. Combining two separation mechanisms a novel micro channel design was developed. The separation unit is based on a micro channel bend structure where typical...... channel dimensions are 20 µm for the plasma channel width, and 50-75 µm for the cell channel. The height of all channels is 100 µm. The micro channel bend works simply on physical and hydrodynamic separation mechanisms without integrated actuators like pumps or valves. For the mass-fabrication of low-cost...

  9. Electrodiffusion Method of Near-Wall Flow Diagnostics in Microfluidic Systems

    Directory of Open Access Journals (Sweden)

    Tihona J.

    2015-01-01

    Full Text Available The electrodiffusion technique has been mostly used for the near-wall flow diagnostics on large scales. A novel technique for fabrication of plastic microfluidic systems with integrated metal microelectrodes (called technique of sacrificed substrate enables us to produce microfluidic devices with precisely shaped sensors for wall shear stress measurements. Several micrometer thick gold sensors, which are built-in a plastic substrate, exhibit good mechanical resistance and smoothness. Proper functioning of prepared chips with microsensors has been first tested in various calibration experiments (polarization curve, sensor response to polarization set-up, steady flow calibration, temperature dependence of diffusivity. Our first results obtained for separating/reattaching flow behind a backward-facing step and for gas-liquid Taylor flow in microchannels then demonstrate its applicability for the detection of near-wall flow reversal, the delimitation of flow - recirculation zones, and the determination of wall shear stress response to moving bubbles. Other applications of these sensors in microfluidics (e.g. characterization of liquid films, capillary waves, bubbles or drops can be also envisaged.

  10. Blood Perfusion in Microfluidic Models of Pulmonary Capillary Networks: Role of Geometry and Hematocrit

    Science.gov (United States)

    Stauber, Hagit; Waisman, Dan; Sznitman, Josue; Technion-IIT Team; Department of Neonatology Carmel Medical Center; Faculty of Medicine-Technion IIT Collaboration

    2015-11-01

    Microfluidic platforms are increasingly used to study blood microflows at true physiological scale due to their ability to overcome manufacturing obstacle of complex anatomical morphologies, such as the organ-specific architectures of the microcirculation. In the present work, we utilize microfluidic platforms to devise in vitro models of the underlying pulmonary capillary networks (PCN), where capillary lengths and diameters are similar to the size of RBCs (~ 5-10 μm). To better understand flow characteristics and dispersion of red blood cells (RBCs) in PCNs, we have designed microfluidic models of alveolar capillary beds inspired by the seminal ``sheet flow'' model of Fung and Sobin (1969). Our microfluidic PCNs feature confined arrays of staggered pillars with diameters of ~ 5,7 and 10 μm, mimicking the dense structure of pulmonary capillary meshes. The devices are perfused with suspensions of RBCs at varying hematocrit levels under different flow rates. Whole-field velocity patterns using micro-PIV and single-cell tracking using PTV are obtained with fluorescently-labelled RBCs and discussed. Our experiments deliver a real-scale quantitative description of RBC perfusion characteristics across the pulmonary capillary microcirculation.

  11. Volumetric measurement of human red blood cells by MOSFET-based microfluidic gate.

    Science.gov (United States)

    Guo, Jinhong; Ai, Ye; Cheng, Yuanbing; Li, Chang Ming; Kang, Yuejun; Wang, Zhiming

    2015-08-01

    In this paper, we present a MOSFET-based (metal oxide semiconductor field-effect transistor) microfluidic gate to characterize the translocation of red blood cells (RBCs) through a gate. In the microfluidic system, the bias voltage modulated by the particles or biological cells is connected to the gate of MOSFET. The particles or cells can be detected by monitoring the MOSFET drain current instead of DC/AC-gating method across the electronic gate. Polystyrene particles with various standard sizes are utilized to calibrate the proposed device. Furthermore, RBCs from both adults and newborn blood sample are used to characterize the performance of the device in distinguishing the two types of RBCs. As compared to conventional DC/AC current modulation method, the proposed device demonstrates a higher sensitivity and is capable of being a promising platform for bioassay analysis. PMID:25349117

  12. Combined Simulation and Experimental Study of Large Deformation of Red Blood Cells in Microfluidic Systems

    OpenAIRE

    Quinn, David J.; Pivkin, Igor; Wong, Sophie Y.; Chiam, Keng-Hwee; Dao, Ming; Karniadakis, George Em; Suresh, Subra

    2010-01-01

    We investigate the biophysical characteristics of healthy human red blood cells (RBCs) traversing microfluidic channels with cross-sectional areas as small as 2.7 × 3 μm. We combine single RBC optical tweezers and flow experiments with corresponding simulations based on dissipative particle dynamics (DPD), and upon validation of the DPD model, predictive simulations and companion experiments are performed in order to quantify cell deformation and pressure–velocity relationships for different ...

  13. Enrichment of prostate cancer cells from blood cells with a hybrid dielectrophoresis and immunocapture microfluidic system

    OpenAIRE

    Huang, Chao; Liu, He; Bander, Neil H.; Kirby, Brian J.

    2013-01-01

    The isolation of circulating tumor cells (CTCs) from cancer patient blood is a technical challenge that is often addressed by microfluidic approaches. Two of the most prominent techniques for rare cancer cell separation, immunocapture and dielectrophoresis (DEP), are currently limited by a performance tradeoff between high efficiency and high purity. The development of a platform capable of these two performance criteria can potentially be facilitated by incorporating both DEP and immunocaptu...

  14. Contact activation of blood coagulation on a defined kaolin/collagen surface in a microfluidic assay

    OpenAIRE

    Zhu, Shu; Diamond, Scott L.

    2014-01-01

    Generation of active Factor XII (FXIIa) triggers blood clotting on artificial surfaces and may also enhance intravascular thrombosis. We developed a patterned kaolin (0 to 0.3 pg/μm2)/type 1 collagen fibril surface for controlled microfluidic clotting assays. Perfusion of whole blood (treated only with a low level of 4 μg/mL of the XIIa inhibitor, corn trypsin inhibitor) drove platelet deposition followed by fibrin formation. At venous wall shear rate (100 s−1), kaolin accelerated onset of fi...

  15. Real-Time Electrical Impedimetric Monitoring of Blood Coagulation Process under Temperature and Hematocrit Variations Conducted in a Microfluidic Chip

    OpenAIRE

    Lei, Kin Fong; Chen, Kuan-Hao; Tsui, Po-Hsiang; Tsang, Ngan-Ming

    2013-01-01

    Blood coagulation is an extremely complicated and dynamic physiological process. Monitoring of blood coagulation is essential to predict the risk of hemorrhage and thrombosis during cardiac surgical procedures. In this study, a high throughput microfluidic chip has been developed for the investigation of the blood coagulation process under temperature and hematocrit variations. Electrical impedance of the whole blood was continuously recorded by on-chip electrodes in contact with the blood sa...

  16. Designing and modeling a centrifugal microfluidic device to separate target blood cells

    International Nuclear Information System (INIS)

    The objective of this study is to design a novel and efficient portable lab-on-a-CD (LOCD) microfluidic device for separation of specific cells (target cells) using magnetic beads. In this study the results are shown for neutrophils as target cells. However, other kinds of target cells can be separated in a similar approach. The designed microfluidics can be utilized as a point of care system for neutrophil detection. This microfluidic system employs centrifugal and magnetic forces for separation. After model validation by the experimental data in the literature (that may be used as a design tool for developing centrifugo-magnetophoretic devices), two models are presented for separation of target cells using magnetic beads. The first model consists of one container in the inlet section and two containers in the outlets. Initially, the inlet container is filled with diluted blood sample which is a mixture of red blood cells (RBCs) plus neutrophils which are attached to Magnetic beads. It is shown that by using centrifugal and magnetic forces, this model can separate all neutrophils with recovery factor of ∼100%. In the second model, due to excess of magnetic beads in usual experimental analysis (to ensure that all target cells are attached to them) the geometry is improved by adding a third outlet for these free magnetic beads. It is shown that at angular velocity of 45 rad s−1, recovery factor of 100% is achievable for RBCs, free magnetic beads and neutrophils as target cells. (paper)

  17. Designing and modeling a centrifugal microfluidic device to separate target blood cells

    Science.gov (United States)

    Shamloo, Amir; Selahi, AmirAli; Madadelahi, Masoud

    2016-03-01

    The objective of this study is to design a novel and efficient portable lab-on-a-CD (LOCD) microfluidic device for separation of specific cells (target cells) using magnetic beads. In this study the results are shown for neutrophils as target cells. However, other kinds of target cells can be separated in a similar approach. The designed microfluidics can be utilized as a point of care system for neutrophil detection. This microfluidic system employs centrifugal and magnetic forces for separation. After model validation by the experimental data in the literature (that may be used as a design tool for developing centrifugo-magnetophoretic devices), two models are presented for separation of target cells using magnetic beads. The first model consists of one container in the inlet section and two containers in the outlets. Initially, the inlet container is filled with diluted blood sample which is a mixture of red blood cells (RBCs) plus neutrophils which are attached to Magnetic beads. It is shown that by using centrifugal and magnetic forces, this model can separate all neutrophils with recovery factor of ~100%. In the second model, due to excess of magnetic beads in usual experimental analysis (to ensure that all target cells are attached to them) the geometry is improved by adding a third outlet for these free magnetic beads. It is shown that at angular velocity of 45 rad s-1, recovery factor of 100% is achievable for RBCs, free magnetic beads and neutrophils as target cells.

  18. Microfluidic amperometric sensor for analysis of nitric oxide in whole blood.

    Science.gov (United States)

    Hunter, Rebecca A; Privett, Benjamin J; Henley, W Hampton; Breed, Elise R; Liang, Zhe; Mittal, Rohit; Yoseph, Benyam P; McDunn, Jonathan E; Burd, Eileen M; Coopersmith, Craig M; Ramsey, J Michael; Schoenfisch, Mark H

    2013-06-18

    Standard photolithographic techniques and a nitric oxide (NO) selective xerogel polymer were utilized to fabricate an amperometric NO microfluidic sensor with low background noise and the ability to analyze NO levels in small sample volumes (~250 μL). The sensor exhibited excellent analytical performance in phosphate buffered saline, including a NO sensitivity of 1.4 pA nM(-1), a limit of detection (LOD) of 840 pM, and selectivity over nitrite, ascorbic acid, acetaminophen, uric acid, hydrogen sulfide, ammonium, ammonia, and both protonated and deprotonated peroxynitrite (selectivity coefficients of -5.3, -4.2, -4.0, -5.0, -6.0, -5.8, -3.8, -1.5, and -4.0, respectively). To demonstrate the utility of the microfluidic NO sensor for biomedical analysis, the device was used to monitor changes in blood NO levels during the onset of sepsis in a murine pneumonia model. PMID:23692300

  19. Combined Simulation and Experimental Study of Large Deformation of Red Blood Cells in Microfluidic Systems

    Science.gov (United States)

    Quinn, David J.; Pivkin, Igor; Wong, Sophie Y.; Chiam, Keng-Hwee; Dao, Ming; Karniadakis, George Em; Suresh, Subra

    2011-01-01

    We investigate the biophysical characteristics of healthy human red blood cells (RBCs) traversing microfluidic channels with cross-sectional areas as small as 2.7 × 3 μm. We combine single RBC optical tweezers and flow experiments with corresponding simulations based on dissipative particle dynamics (DPD), and upon validation of the DPD model, predictive simulations and companion experiments are performed in order to quantify cell deformation and pressure–velocity relationships for different channel sizes and physiologically relevant temperatures. We discuss conditions associated with the shape transitions of RBCs along with the relative effects of membrane and cytosol viscosity, plasma environments, and geometry on flow through microfluidic systems at physiological temperatures. In particular, we identify a cross-sectional area threshold below which the RBC membrane properties begin to dominate its flow behavior at room temperature; at physiological temperatures this effect is less profound. PMID:21240637

  20. Fabrication and Characterization of a Microfluidic Device to Ultrapurify Blood Samples

    KAUST Repository

    Tallerico, Marco

    2015-05-04

    The improvement of blood cell sorting techniques in recent years have attracted the attention of many researchers due to the possible benefits that these methods can lead in biology, regenerative medicine, materials science and therapeutic area. In this work a cell sorting technique based on filtration is described. The separation occurs by means of a microfluidic device, suitably designed, manufactured and tested, that is connected to an external experimental set-up. The fabrication process can be divided in two parts: at first it is described the manufacturing process of a filtering membrane, with holes of specific size that allow the passage of only certain cell types. Following the microfluidic device is fabricated through the mechanical micromilling. The membrane and the microdevice are suitably bonded and tested by means of an external connection with syringe pumps that inject blood samples at specific flow rates. The device is designed to separate blood cells and tumor cells only by using differences in size and shape. In particular during the first experiments red blood cells and platelets are sorted from white blood cells; in the other experiments red blood cells and platelets are separated from white blood cells and tumor cells. The microdevice has proven to be very efficient, in fact a capture efficiency of 99% is achieved. For this reason it could be used in identification and isolation of circulating tumor cells, a very rare cancer cell type whose presence in the bloodstream could be symptom of future solid tumor formation. The various experiments have also demonstrated that tumor cells survive even after the separation treatment, and then the suffered stress during the sorting process does not harm the biological sample.

  1. Soft inertial microfluidics for high throughput separation of bacteria from human blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zhigang; Willing, Ben; Bjerketorp, Joakim; Jansson, Janet K.; Hjort, Klas

    2009-01-05

    We developed a new approach to separate bacteria from human blood cells based on soft inertial force induced migration with flow defined curved and focused sample flow inside a microfluidic device. This approach relies on a combination of an asymmetrical sheath flow and proper channel geometry to generate a soft inertial force on the sample fluid in the curved and focused sample flow segment to deflect larger particles away while the smaller ones are kept on or near the original flow streamline. The curved and focused sample flow and inertial effect were visualized and verified using a fluorescent dye primed in the device. First the particle behavior was studied in detail using 9.9 and 1.0 {micro}m particles with a polymer-based prototype. The prototype device is compact with an active size of 3 mm{sup 2}. The soft inertial effect and deflection distance were proportional to the fluid Reynolds number (Re) and particle Reynolds number (Re{sub p}), respectively. We successfully demonstrated separation of bacteria (Escherichia coli) from human red blood cells at high cell concentrations (above 10{sup 8}/mL), using a sample flow rate of up to 18 {micro}L/min. This resulted in at least a 300-fold enrichment of bacteria at a wide range of flow rates with a controlled flow spreading. The separated cells were proven to be viable. Proteins from fractions before and after cell separation were analyzed by gel electrophoresis and staining to verify the removal of red blood cell proteins from the bacterial cell fraction. This novel microfluidic process is robust, reproducible, simple to perform, and has a high throughput compared to other cell sorting systems. Microfluidic systems based on these principles could easily be manufactured for clinical laboratory and biomedical applications.

  2. Sample pretreatment microfluidic chip for DNA extraction from rat peripheral blood

    Institute of Scientific and Technical Information of China (English)

    CHEN Xing; CUI Dafu; LIU Changchun; LI Hui; ZHAO Weixing

    2007-01-01

    A sample pretreatment microfluidic chip was described based on the principle of solid phase extraction and micro electro mechanical system technology.Oxidized porous silicon with the large surface area as the solid phase matrix for absorption of DNA from a biological sample can greatly improve the DNA yield.The factors that could affect the DNA yield were analyzed and the preparation technology and the experiment procedure were improved.The DNA purification process from the rat peripheral blood can be achieved and the DNA yield is 24 ng/(μL whole blood),which can reach the level of the commercial DNA purification kits.Furthermore,the DNA extracted from the whole blood can be amplified by polymerase chain reaction,which can achieve a high efficiency of the amplification.

  3. Micro-fluidic module for blood cell separation for gene expression radiobiological assays

    International Nuclear Information System (INIS)

    Advances in molecular techniques have improved discovery of biomarkers associated with radiation exposure. Gene expression techniques have been demonstrated as effective tools for biodosimetry, and different assay platforms with different chemistries are now available. One of the main challenges is to integrate the sample preparation processing of these assays into micro-fluidic platforms to be fully automated for point-of-care medical countermeasures in the case of a radiological event. Most of these assays follow the same workflow processing that comprises first the collection of blood samples followed by cellular and molecular sample preparation. The sample preparation is based on the specific reagents of the assay system and depends also on the different subsets of cells population and the type of biomarkers of interest. In this article, the authors present a module for isolation of white blood cells from peripheral blood as a prerequisite for automation of gene expression assays on a micro-fluidic cartridge. For each sample condition, the gene expression platform can be adapted to suit the requirements of the selected assay chemistry (authors)

  4. Blood coagulation screening using a paper-based microfluidic lateral flow device.

    Science.gov (United States)

    Li, H; Han, D; Pauletti, G M; Steckl, A J

    2014-10-21

    A simple approach to the evaluation of blood coagulation using a microfluidic paper-based lateral flow assay (LFA) device for point-of-care (POC) and self-monitoring screening is reported. The device utilizes whole blood, without the need for prior separation of plasma from red blood cells (RBC). Experiments were performed using animal (rabbit) blood treated with trisodium citrate to prevent coagulation. CaCl2 solutions of varying concentrations are added to citrated blood, producing Ca(2+) ions to re-establish the coagulation cascade and mimic different blood coagulation abilities in vitro. Blood samples are dispensed into a paper-based LFA device consisting of sample pad, analytical membrane and wicking pad. The porous nature of the cellulose membrane separates the aqueous plasma component from the large blood cells. Since the viscosity of blood changes with its coagulation ability, the distance RBCs travel in the membrane in a given time can be related to the blood clotting time. The distance of the RBC front is found to decrease linearly with increasing CaCl2 concentration, with a travel rate decreasing from 3.25 mm min(-1) for no added CaCl2 to 2.2 mm min(-1) for 500 mM solution. Compared to conventional plasma clotting analyzers, the LFA device is much simpler and it provides a significantly larger linear range of measurement. Using the red colour of RBCs as a visible marker, this approach can be utilized to produce a simple and clear indicator of whether the blood condition is within the appropriate range for the patient's condition. PMID:25144164

  5. Differential white cell count by centrifugal microfluidics.

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, Gregory Jon; Tentori, Augusto M.; Schaff, Ulrich Y.

    2010-07-01

    We present a method for counting white blood cells that is uniquely compatible with centrifugation based microfluidics. Blood is deposited on top of one or more layers of density media within a microfluidic disk. Spinning the disk causes the cell populations within whole blood to settle through the media, reaching an equilibrium based on the density of each cell type. Separation and fluorescence measurement of cell types stained with a DNA dye is demonstrated using this technique. The integrated signal from bands of fluorescent microspheres is shown to be proportional to their initial concentration in suspension. Among the current generation of medical diagnostics are devices based on the principle of centrifuging a CD sized disk functionalized with microfluidics. These portable 'lab on a disk' devices are capable of conducting multiple assays directly from a blood sample, embodied by platforms developed by Gyros, Samsung, and Abaxis. [1,2] However, no centrifugal platform to date includes a differential white blood cell count, which is an important metric complimentary to diagnostic assays. Measuring the differential white blood cell count (the relative fraction of granulocytes, lymphocytes, and monocytes) is a standard medical diagnostic technique useful for identifying sepsis, leukemia, AIDS, radiation exposure, and a host of other conditions that affect the immune system. Several methods exist for measuring the relative white blood cell count including flow cytometry, electrical impedance, and visual identification from a stained drop of blood under a microscope. However, none of these methods is easily incorporated into a centrifugal microfluidic diagnostic platform.

  6. Role of Microfluidics in Blood-Brain Barrier Permeability Cell Culture Modeling: Relevance to CNS Disorders.

    Science.gov (United States)

    Rusanov, Alexander L; Luzgina, Natalia G; Barreto, George E; Aliev, Gjumrakch

    2016-01-01

    In vitro modeling of the human blood-brain barrier (BBB) is critical for pre-clinical evaluation and predicting the permeability of newly developed potentially neurotoxic and neurotrophic drugs. Here we summarize the specific structural and functional features of endothelial cells as a key component of the BBB and compare analysis of different cell culture models in reflecting these features. Particular attention is paid to cellular models of the BBB in microfluidic devices capable of circulating nutrient media to simulate the blood flow of the brain. In these conditions, it is possible to reproduce a number of factors affecting endothelial cells under physiological conditions, including shear stress. In comparison with static cell models, concentration gradients, which determine the velocity of transport of substances, reproduce more accurately conditions of nutrient medium flow, since they eliminate the accumulation of substances near the basal membrane of cells, not typical for the situation in vivo. Co-cultivation of different types of cells forming the BBB, in separate cell chambers connected by microchannels, allows to evaluate the mutual influences of cells under normal conditions and when exposed to the test substance. New experimental possibilities that can be achieved through modeling of BBB in microfluidic devices determine the feasibility of their use in the practice for pre-clinical studies of novel drugs against neurodegenerative diseases. PMID:26831260

  7. Performance Evaluation of Fast Microfluidic Thermal Lysis of Bacteria for Diagnostic Sample Preparation

    Directory of Open Access Journals (Sweden)

    Evangelyn C. Alocilja

    2013-01-01

    Full Text Available Development of new diagnostic platforms that incorporate lab-on-a-chip technologies for portable assays is driving the need for rapid, simple, low cost methods to prepare samples for downstream processing or detection. An important component of the sample preparation process is cell lysis. In this work, a simple microfluidic thermal lysis device is used to quickly release intracellular nucleic acids and proteins without the need for additional reagents or beads used in traditional chemical or mechanical methods (e.g., chaotropic salts or bead beating. On-chip lysis is demonstrated in a multi-turn serpentine microchannel with external temperature control via an attached resistive heater. Lysis was confirmed for Escherichia coli by fluorescent viability assay, release of ATP measured with bioluminescent assay, release of DNA measured by fluorometry and qPCR, as well as bacterial culture. Results comparable to standard lysis techniques were achievable at temperatures greater than 65 °C and heating durations between 1 and 60 s.

  8. Identification of malaria parasite-infected red blood cell surface aptamers by inertial microfluidic SELEX (I-SELEX)

    Science.gov (United States)

    Birch, Christina M.; Hou, Han Wei; Han, Jongyoon; Niles, Jacquin C.

    2015-07-01

    Plasmodium falciparum malaria parasites invade and remodel human red blood cells (RBCs) by trafficking parasite-synthesized proteins to the RBC surface. While these proteins mediate interactions with host cells that contribute to disease pathogenesis, the infected RBC surface proteome remains poorly characterized. Here we use a novel strategy (I-SELEX) to discover high affinity aptamers that selectively recognize distinct epitopes uniquely present on parasite-infected RBCs. Based on inertial focusing in spiral microfluidic channels, I-SELEX enables stringent partitioning of cells (efficiency ≥ 106) from unbound oligonucleotides at high volume throughput (~2 × 106 cells min-1). Using an RBC model displaying a single, non-native antigen and live malaria parasite-infected RBCs as targets, we establish suitability of this strategy for de novo aptamer selections. We demonstrate recovery of a diverse set of aptamers that recognize distinct, surface-displayed epitopes on parasite-infected RBCs with nanomolar affinity, including an aptamer against the protein responsible for placental sequestration, var2CSA. These findings validate I-SELEX as a broadly applicable aptamer discovery platform that enables identification of new reagents for mapping the parasite-infected RBC surface proteome at higher molecular resolution to potentially contribute to malaria diagnostics, therapeutics and vaccine efforts.

  9. Real-time electrical impedimetric monitoring of blood coagulation process under temperature and hematocrit variations conducted in a microfluidic chip.

    Directory of Open Access Journals (Sweden)

    Kin Fong Lei

    Full Text Available Blood coagulation is an extremely complicated and dynamic physiological process. Monitoring of blood coagulation is essential to predict the risk of hemorrhage and thrombosis during cardiac surgical procedures. In this study, a high throughput microfluidic chip has been developed for the investigation of the blood coagulation process under temperature and hematocrit variations. Electrical impedance of the whole blood was continuously recorded by on-chip electrodes in contact with the blood sample during coagulation. Analysis of the impedance change of the blood was conducted to investigate the characteristics of blood coagulation process and the starting time of blood coagulation was defined. The study of blood coagulation time under temperature and hematocrit variations was shown a good agreement with results in the previous clinical reports. The electrical impedance measurement for the definition of blood coagulation process provides a fast and easy measurement technique. The microfluidic chip was shown to be a sensitive and promising device for monitoring blood coagulation process even in a variety of conditions. It is found valuable for the development of point-of-care coagulation testing devices that utilizes whole blood sample in microliter quantity.

  10. Polymeric nanoparticles assembled with microfluidics for drug delivery across the blood-brain barrier

    Science.gov (United States)

    Tavares, M. R.; de Menezes, L. R.; do Nascimento, D. F.; Souza, D. H. S.; Reynaud, F.; Marques, M. F. V.; Tavares, M. I. B.

    2016-07-01

    The blood-brain barrier (BBB) is a challenge in the treatment of some diseases, since it prevents many drugs from reaching therapeutic concentrations in the brain. In this context, there is a growing interest in nanoparticles for drug delivery, since they are able to cross this barrier and target the brain. The use of polymeric materials in the development of these nanoparticles has been extensively studied. It has already been demonstrated that these nanosystems have the ability to cross the BBB, which allows effective drug release into the brain. Biodegradable polymers provide a great advantage in the development of nanosystems, but modifications of the nanoparticles' surface is essential. The traditional batch methods lack precise control over the processes of nucleation and growth, resulting in poor control over final properties of the nanoparticles. Therefore, microfluidics could be used to achieve a better production environment for the fabrication of nano- structured drug delivery systems. This study provides a brief review of: the BBB, the polymeric nanoparticles with the ability to overcome the barrier, the properties of the most used polymeric matrices, and the nanostructured drug delivery systems assembled with microfluidics.

  11. Monitoring time course of human whole blood coagulation using a microfluidic dielectric sensor with a 3D capacitive structure.

    Science.gov (United States)

    Maji, Debnath; Suster, Michael A; Stavrou, Evi; Gurkan, Umut A; Mohseni, Pedram

    2015-08-01

    This paper reports on the design, fabrication, and testing of a microfluidic sensor for dielectric spectroscopy (DS) of human whole blood during coagulation. The sensor employs a three-dimensional (3D), parallel-plate, capacitive sensing structure with a floating electrode integrated into a microfluidic channel. Using an impedance analyzer and after a 5-point calibration, the sensor is shown to measure the real part of complex relative dielectric permittivity of human whole blood in a frequency range of 10kHz to 100MHz. The temporal variation of dielectric permittivity at 1MHz for human whole blood from three different healthy donors shows a peak in permittivity at ~ 4 to 5 minutes, which also corresponds to the onset of CaCl2-initiated coagulation of the blood sample verified visually. PMID:26737635

  12. PMMA microfluidic devices with three-dimensional features for blood cell filtration

    International Nuclear Information System (INIS)

    In this paper, a PMMA (polymethylmethacrylate) microfluidic device with filtration features fabricated by hot embossing and thermal bonding was used to separate RBCs (red blood cells) from whole rat blood. The filtration features are composed of 20 µm deep and 300 µm wide main channels, 15 µm high and 25 µm wide micro-dams which were fabricated in main channels and an array of orthogonal side channels for perfusion flow to collect RBCs. As rat blood advances through the main channels, a perfusion flow through the side channels washes away RBCs which are sufficiently small to enter the gaps between the micro-dams and the cover plate. A silicon mold fabricated by dry etching was used to produce three-dimensional filtration features on PMMA substrates. Oxygen plasma treatment was used to increase the adhesive ability of PMMA surfaces, which enables thermal bonding at 86 °C and 0.75 MPa. The distortion of microchannels and micro-dams has been minimized, which makes the value of the gap between the micro-dam and the cover plate appropriate for cell filtration

  13. Performance study of microfluidic devices for blood plasma separation—a designer’s perspective

    Science.gov (United States)

    Tripathi, Siddhartha; Bala Varun Kumar, Y. V.; Prabhakar, Amit; Joshi, Suhas S.; Agrawal, Amit

    2015-08-01

    In this work, design and experiments on various blood plasma microdevices based on hydrodynamic flow separation techniques is carried out. We study their performance as a function of dependent governing parameters such as flow rate, feed hematocrit, and microchannel geometry. This work focuses on understanding separation phenomena in simple geometries; subsequently, individual simple geometrical parameters and biophysical effects are combined to fabricate hybridized designs, resulting in higher separation efficiencies. The distinctive features of our microfluidic devices are that they employ elevated dimensions (of the order of hundreds of microns), and thereby can be operated continuously over sufficient duration without clogging, while simplicity of fabrication makes them cost effective. The microdevices have been experimentally demonstrated over the entire range of hematocrit (i.e. from Hct 7% to Hct 45%). A high separation efficiency of about (78.34  ±  2.7)% with pure blood is achieved in our best hybrid design. We believe that the theory and experimental results presented in this study will aid designers and researchers working in the field of blood plasma separation microdevices.

  14. Design of Smart Polymer-Protein Conjugates and Smart Magnetic Nanoparticles for Use in Microfluidic Diagnostic Assays

    Institute of Scientific and Technical Information of China (English)

    Allan; S.Hoffman

    2007-01-01

    1 Results In this talk,I will describe the design,synthesis and application of smart polymers for use in microfluidic diagnostic devices.We are synthesizing a variety of temperature- and pH-responsive polymers using RAFT living free radical polymerization techniques.This allows us to control molecular weight and to achieve a narrow MW distribution of the polymers. Furthermore,RAFT polymers have reactive end groups that are used to conjugate the polymers to proteins.We are also using those groups to bind...

  15. Microfluidics in the selection of affinity reagents for the detection of cancer: paving a way towards future diagnostics.

    Science.gov (United States)

    Hung, Lien-Yu; Wang, Chih-Hung; Fu, Chien-Yu; Gopinathan, Priya; Lee, Gwo-Bin

    2016-08-01

    Microfluidic technologies have miniaturized a variety of biomedical applications, and these chip-based systems have several significant advantages over their large-scale counterparts. Recently, this technology has been used for automating labor-intensive and time-consuming screening processes, whereby affinity reagents, including aptamers, peptides, antibodies, polysaccharides, glycoproteins, and a variety of small molecules, are used to probe for molecular biomarkers. When compared to conventional methods, the microfluidic approaches are faster, more compact, require considerably smaller quantities of samples and reagents, and can be automated. Furthermore, they allow for more precise control of reaction conditions (e.g., pH, temperature, and shearing forces) such that more efficient screening can be performed. A variety of affinity reagents for targeting cancer cells or cancer biomarkers are now available and will likely replace conventional antibodies. In this review article, the selection of affinity reagents for cancer cells or cancer biomarkers on microfluidic platforms is reviewed with the aim of highlighting the utility of such approaches in cancer diagnostics. PMID:27381813

  16. High-throughput and clogging-free microfluidic filtration platform for on-chip cell separation from undiluted whole blood.

    Science.gov (United States)

    Cheng, Yinuo; Ye, Xiongying; Ma, Zengshuai; Xie, Shuai; Wang, Wenhui

    2016-01-01

    Rapid separation of white blood cells from whole blood sample is often required for their subsequent analyses of functions and phenotypes, and many advances have been made in this field. However, most current microfiltration-based cell separation microfluidic chips still suffer from low-throughput and membrane clogging. This paper reports on a high-throughput and clogging-free microfluidic filtration platform, which features with an integrated bidirectional micropump and commercially available polycarbonate microporous membranes. The integrated bidirectional micropump enables the fluid to flush micropores back and forth, effectively avoiding membrane clogging. The microporous membrane allows red blood cells passing through high-density pores in a cross-flow mixed with dead-end filtration mode. All the separation processes, including blood and buffer loading, separation, and sample collection, are automatically controlled for easy operation and high throughput. Both microbead mixture and undiluted whole blood sample are separated by the platform effectively. In particular, for white blood cell separation, the chip recovered 72.1% white blood cells with an over 232-fold enrichment ratio at a throughput as high as 37.5 μl/min. This high-throughput, clogging-free, and highly integrated platform holds great promise for point-of-care blood pretreatment, analysis, and diagnosis applications. PMID:26909124

  17. Microfluidic structures for flow cytometric analysis of hydrodynamically focussed blood cells fabricated by ultraprecision micromachining.

    Science.gov (United States)

    Kummrow, A; Theisen, J; Frankowski, M; Tuchscheerer, A; Yildirim, H; Brattke, K; Schmidt, M; Neukammer, J

    2009-04-01

    We present three-dimensional microfluidic structures with integrated optical fibers, mirrors and electrodes for flow cytometric analysis of blood cells. Ultraprecision milling technique was used to fabricate different flow cells featuring single-stage and two-stage cascaded hydrodynamic focusing of particles by a sheath flow. Two dimensional focussing of the sample fluid was proven by fluorescence imaging in horizontal and vertical directions and found to agree satisfactorily with finite element calculations. Focussing of the sample stream down to 5 microm at a particle velocity of 3 m s(-1) is accessible while maintaining stable operation for sample flow rates of up to 20 microL min(-1). In addition to fluorescence imaging, the micro-flow cells were characterised by measurements of pulse shapes and pulse height distributions of monodisperse microspheres. We demonstrated practical use of the microstructures for cell differentiation employing light scatter to distinguish platelets and red blood cells. Furthermore, T-helper lymphocytes labelled by monoclonal antibodies were identified by measuring side scatter and fluorescence. PMID:19294310

  18. Direct current insulator based dielectrophoresis (DC-iDEP) microfluidic chip for blood plasma separation

    OpenAIRE

    Mohammadi, Mahdi

    2015-01-01

    Lab-on-a-Chip (LOC) integrated microfluidics has been a powerful tool for new developments in analytical chemistry. These microfluidic systems enable the miniaturization, integration and automation of complex biochemical assays through the reduction of reagent use and enabling portability.Cell and particle separation in microfluidic systems has recently gained significant attention in many sample preparations for clinical procedures. Direct-current insulator-based dielectrophoresis (DC-iDEP) ...

  19. Microfluidic modeling of the effects of nanoparticles on the blood-brain barrier in flow

    Science.gov (United States)

    Schwait, Craig; Hartman, Ryan; Bao, Yuping; Xu, Yaolin

    2011-11-01

    The difficulty of diffusing drugs across the blood-brain barrier (BBB) has caused an impasse for many brain treatments. Nanoparticles (NPs), to which drugs can adsorb, attach, or be entrapped, have the potential to deliver drugs past the BBB. Before nanoparticles can be used, their effects on the BBB and brain must be ascertained. Previous steady-state studies fall short for closely modeling in vivo conditions . Convection of nanoparticles is ignored, and endothelial cells' (ECs) morphology differs based on loading conditions; in vitro loading with continuous flow exhibit ECs indicating a more similar in vivo phenotype. NPs interact with monocytes prior to the BBB, and their toxicity effects were measured in flow conditions using both Trypan Blue cell counting and cell proliferation assays. The microfluidic device designed to model the BBB contained a concentric PES hollow fiber porous membrane in PFA tubing. Full use of the device will include ECs adhered on the inner surface and astrocytes adhered to the outer surface of the PES membrane to model cerebrovascular capillaries. Funded by NSF REU Site 1062611.

  20. Microfluidic assay for precise measurements of mouse, rat, and human neutrophil chemotaxis in whole-blood droplets.

    Science.gov (United States)

    Jones, Caroline N; Hoang, Anh N; Martel, Joseph M; Dimisko, Laurie; Mikkola, Amy; Inoue, Yoshitaka; Kuriyama, Naohide; Yamada, Marina; Hamza, Bashar; Kaneki, Masao; Warren, H Shaw; Brown, Diane E; Irimia, Daniel

    2016-07-01

    Animal models of human disease differ in innate immune responses to stress, pathogens, or injury. Precise neutrophil phenotype measurements could facilitate interspecies comparisons. However, such phenotype comparisons could not be performed accurately with the use of current assays, as they require the separation of neutrophils from blood using species-specific protocols, and they introduce distinct artifacts. Here, we report a microfluidic technology that enables robust characterization of neutrophil migratory phenotypes in a manner independent of the donor species and performed directly in a droplet of whole blood. The assay relies on the particular ability of neutrophils to deform actively during chemotaxis through microscale channels that block the advance of other blood cells. Neutrophil migration is measured directly in blood, in the presence of other blood cells and serum factors. Our measurements reveal important differences among migration counts, velocity, and directionality among neutrophils from 2 common mouse strains, rats, and humans. PMID:26819316

  1. Microfluidic-based speckle analysis for sensitive measurement of erythrocyte aggregation: A comparison of four methods for detection of elevated erythrocyte aggregation in diabetic rat blood

    OpenAIRE

    Yeom, Eunseop; Lee, Sang Joon

    2015-01-01

    Biochemical alterations in the plasma and red blood cell (RBC) membrane of diabetic blood lead to excessive erythrocyte aggregation (EA). EA would significantly impede the blood flow and increase the vascular flow resistance contributing to peripheral vascular diseases. In this study, a simple microfluidic-based method is proposed to achieve sensitive detection of hyperaggregation. When a blood sample is delivered into the device, images of blood flows are obtained with a short exposure time ...

  2. Effects of Nanotexture on Electrical Profiling of Single Tumor Cell and Detection of Cancer from Blood in Microfluidic Channels

    Science.gov (United States)

    Islam, Muhymin; Motasim Bellah, Mohammad; Sajid, Adeel; Raziul Hasan, Mohammad; Kim, Young-Tae; Iqbal, Samir M.

    2015-09-01

    Microfluidic channels have been implemented to detect cancer cells from blood using electrical measurement of each single cell from the sample. Every cell provided characteristic current profile based on its mechano-physical properties. Cancer cells not only showed higher translocation time and peak amplitude compared to blood cells, their pulse shape was also distinctively different. Prevalent microfluidic channels are plain but we created nanotexture on the channel walls using micro reactive ion etching (micro-RIE). The translocation behaviors of the metastatic renal cancer cells through plain and nanotextured PDMS microchannels showed clear differences. Nanotexture enhanced the cell-surface interactions and more than 50% tumor cells exhibited slower translocation through nanotextured channels compared to plain devices. On the other hand, most of the blood cells had very similar characteristics in both channels. Only 7.63% blood cells had slower translocation in nanotextured microchannels. The tumor cell detection efficiency from whole blood increased by 14% in nanotextured microchannels compared to plain channels. This interesting effect of nanotexture on translocation behavior of tumor cells is important for the early detection of cancer.

  3. Integrated Microfluidic Nucleic Acid Isolation, Isothermal Amplification, and Amplicon Quantification

    OpenAIRE

    Mauk, Michael G.; Changchun Liu; Jinzhao Song; Bau, Haim H

    2015-01-01

    Microfluidic components and systems for rapid (<60 min), low-cost, convenient, field-deployable sequence-specific nucleic acid-based amplification tests (NAATs) are described. A microfluidic point-of-care (POC) diagnostics test to quantify HIV viral load from blood samples serves as a representative and instructive example to discuss the technical issues and capabilities of “lab on a chip” NAAT devices. A portable, miniaturized POC NAAT with performance comparable to conventional PCR (poly...

  4. 21 CFR 864.9160 - Blood group substances of nonhuman origin for in vitro diagnostic use.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blood group substances of nonhuman origin for in... Used In Establishments That Manufacture Blood and Blood Products § 864.9160 Blood group substances of nonhuman origin for in vitro diagnostic use. (a) Identification. Blood group substances of nonhuman...

  5. Electrodiffusion Method of Near-Wall Flow Diagnostics in Microfluidic Systems

    Czech Academy of Sciences Publication Activity Database

    Tihon, Jaroslav; Pěnkavová, Věra; Stanovský, Petr; Vejražka, Jiří

    CEDEX A: E D P SCIENCES, 2015 - (Dančová, P.; Vít, T.), 02098. (EFM - Experimental Fluid Mechanics). ISSN 2100-014X. [Experimental Fluid Mechanics 2014. Český Krumlov (CZ), 18.11.2014-21.11.2014] R&D Projects: GA ČR(CZ) GAP101/12/0585 Institutional support: RVO:67985858 Keywords : microfluidics * electrodiffusion method * wall shear stress Subject RIV: CI - Industrial Chemistry, Chemical Engineering http://www.epj-conferences.org/articles/epjconf/abs/2015/11/contents/contents.html

  6. Electrodiffusion Method of Near-Wall Flow Diagnostics in Microfluidic Systems

    Czech Academy of Sciences Publication Activity Database

    Tihon, Jaroslav; Pěnkavová, Věra; Stanovský, Petr; Vejražka, Jiří

    CEDEX A : E D P SCIENCES, 2015 - (Dančová, P.; Vít, T.), 02098 ISSN 2100-014X. - (EFM - Experimental Fluid Mechanics). [Experimental Fluid Mechanics 2014. Český Krumlov (CZ), 18.11.2014-21.11.2014] R&D Projects: GA ČR(CZ) GAP101/12/0585 Institutional support: RVO:67985858 Keywords : microfluidics * electrodiffusion method * wall shear stress Subject RIV: CI - Industrial Chemistry, Chemical Engineering http://www.epj-conferences.org/articles/epjconf/abs/2015/11/contents/contents.html

  7. Picoliter droplet microfluidic immunosorbent platform for point-of-care diagnostics of tetanus

    International Nuclear Information System (INIS)

    We have developed a sensitive, specific, rapid and low cost picoliter microsphere-based platform for bioanalyte detection and quantification. In this method, a biological sample, biosensing microspheres, and fluorescently labeled detection (secondary) antibodies are co-encapsulated to capture the analyte (here: human anti-tetanus immunoglobulin G) on the surface of the microsphere in microfluidic pL-sized droplets. The absorption of the analyte and detecting antibodies on the microsphere concentrate the fluorescent signal in correlation with analyte concentration. Using our platform and commercially available antibodies, we were able to quantify anti-tetanus antibodies in human serum. In comparison to standard bulk immunosorbent assays, the microfluidic droplet platform presented here reduces the reagent volume by four orders of magnitude, while fast reagent mixing reduces the detection time from hours to minutes. We consider this platform to be a major leap forward in the miniaturization of immunosorbent assays and to provide a rapid and low cost tool for global point-of-care. (author)

  8. COMPARABLE CYTOLOGICAL DIAGNOSTIC OF BLOOD SMEARS ON BABESIA INFECTION

    Directory of Open Access Journals (Sweden)

    Pokhyl S.І.

    2015-05-01

    Full Text Available In last time Babesiosis as a tick-borne hemoprotozoans human disease have a very important role in differentil diagnostics of modern infectious medicine. It caused by protozon of the genus Babesia, which invade and destory erythrocytes. Babesiosis olso has been called tick fever. So, Babesia has been known by other genus names, including Nuttallia, Microbabesia, Babesialla, and Gonderia. Because all Babesia species are piroplasms, a more inclusive term for anthropozoonotic infections caused by these organisms would be piroplasmosis.They detective complicacy are bild that, tick-borne disease agents from prolongate life cycles involving arthropod and vertebrate host. The complexity is enhanced by the diversity of hosts in different biotopes, which depends on factors life type of vegetation, climate and/or human influence, such as restoration of former industrial sites, which leads to the development of new biotopes. So, on the one hand, new habitats for plants and animals including ticks, and nature are created. About the first case of babesiosis infection was reported as a cause of human sickness in 1969 in northeastern United State. Several hundred cases are now reported from this region each year. The disease is characterized by a grandual oncet of malaise with anorexia, fever, headaches, myalgia, and other vague symptoms, which may persist for long period. Occasionally dangerous fulminating infections occur particularly in immunocompromised or aged individuals. The purpose of the present research was to study of the cytological diagnostic of blood smears from object’s with the Babesia infection. Materials and methods. Blood smears (by Romanovsky- Gimze (standart, Wright’s standart and staining, the author’s modification, 2014 of domestic dogs (n = 31 of both sexes with Babesia infection at the age from 3 months to 6 years served as the material for the study. The preparations were fixed during 1-2 seconds with 96 % ethyl alcohol. Then

  9. Diagnostic Methods for Detection of Blood-Borne Candidiasis.

    Science.gov (United States)

    Clancy, Cornelius J; Nguyen, M Hong

    2016-01-01

    β-D-glucan (Fungitell) and polymerase chain reaction-based (T2Candida) assays of blood samples are FDA-approved adjuncts to cultures for diagnosing candidemia and other types of invasive candidiasis, but their clinical roles are unclear. In this chapter, we describe laboratory protocols for performing Fungitell and T2Candida assays. We then discuss step-by-step methods for interpreting test results at the bedside using a Bayesian framework, and for incorporating assays into rational patient management strategies. Prior to interpreting results, clinicians must recognize that test performance varies based on the type of invasive candidiasis being diagnosed. In general, the type of invasive candidiasis that is most likely in a given patient can be identified, and the pretest likelihood of disease estimated. From there, positive and negative predictive values (PPV, NPV) for an assay can be calculated. At a population level, tests can be incorporated into screening strategies for antifungal treatment. NPV and PPV thresholds can be defined for discontinuing antifungal prophylaxis or initiating preemptive treatment, respectively. Using the thresholds, it is possible to assign windows of pretest likelihood for invasive candidiasis (and corresponding patient populations) in which tests are most likely to valuable. At the individual patient level, tests may be useful outside of the windows proposed for screening populations. The interpretive and clinical decision-making processes we discuss will be applicable to other diagnostic assays as they enter the clinic, and to existing assays as more data emerge from various populations. PMID:26519076

  10. Investigations of significance of blood smear results in diagnostics of infectious and parasitic diseases in dogs

    OpenAIRE

    Potkonjak Aleksandar; Lako Branislav; Belić Branislava; Milošević Nikolina; Stevančević Ognjen; Cincović Marko; Lako Bjanka

    2010-01-01

    The microscopic examination of stained smears of peripheral blood is of vital significance in the speedy diagnostics of infectious and parasitic diseases, in particular during the stage of infection when the cause is present in the blood, or blood cells. It is sometimes possible to make a definitive diagnosis of an infectious or parasitic disease following an examination of a stained smear of the peripheral blood. Since microscopic examinations of a peripheral blood smear are applied increasi...

  11. Resonance Raman study of the oxygenation cycle of optically trapped single red blood cells in a microfluidic system

    Science.gov (United States)

    Ramser, Kerstin; Logg, Katarina; Enger, Jonas; Goksor, Mattias; Kall, Mikael; Hanstorp, Dag

    2004-10-01

    The average environmental response of red blood cells (RBCs) is routinely measured in ensemble studies, but in such investigations valuable information on the single cell level is obscured. In order to elucidate this hidden information is is important to enable the selection of single cells with certain properties while subsequent dynamics triggered by environmental stimulation are recorded in real time. It is also desirable to manipulate and control the cells under phsyiological conditions. As shown here, this can be achieved by combining optical tweezers with a confocal Raman set-up equipped with a microfluidic system. A micro-Raman set-up is combined with an optical trap with separate optical paths, lasers and objectives, which enables the acquisition of resonance Raman profils of single RBCs. The microfluidic system, giving full control over the media surrounding the cell, consists of a pattern of channels and reservoirs produced by electron beam lithography and moulded in PDMS. Fresh Hepes buffer or buffer containing sodium dithionite are transported through the channels using electro-osmotic flow, while the direct Raman response of the single optically trapped RBC is registered in another reservoir in the middle of the channel. Thus, it is possible to monitor the oxygenation cycle in a single cell and to study photo-induced chemistry. This experimental set-up has high potential for monitoring the drug response or conformational changes caused by other environmental stimuli for many types of single functional cells since "in vivo" conditions can be created.

  12. Unconventional microfluidics: expanding the discipline

    OpenAIRE

    Nawaz, Ahmad Ahsan; Mao, Xiaole; Stratton, Zackary S.; Huang, Tony Jun

    2013-01-01

    Since its inception, the discipline of microfluidics has been harnessed for innovations in the biomedicine/chemistry fields—and to great effect. This success has had the natural side-effect of stereotyping microfluidics as a platform for medical diagnostics and miniaturized lab processes. But microfluidics has more to offer. And very recently, some researchers have successfully applied microfluidics to fields outside its traditional domains. In this Focus article, we highlight notable example...

  13. Deformability measurement of red blood cells using a microfluidic channel array and an air cavity in a driving syringe with high throughput and precise detection of subpopulations.

    Science.gov (United States)

    Kang, Yang Jun; Ha, Young-Ran; Lee, Sang-Joon

    2016-01-01

    Red blood cell (RBC) deformability has been considered a potential biomarker for monitoring pathological disorders. High throughput and detection of subpopulations in RBCs are essential in the measurement of RBC deformability. In this paper, we propose a new method to measure RBC deformability by evaluating temporal variations in the average velocity of blood flow and image intensity of successively clogged RBCs in the microfluidic channel array for specific time durations. In addition, to effectively detect differences in subpopulations of RBCs, an air compliance effect is employed by adding an air cavity into a disposable syringe. The syringe was equally filled with a blood sample (V(blood) = 0.3 mL, hematocrit = 50%) and air (V(air) = 0.3 mL). Owing to the air compliance effect, blood flow in the microfluidic device behaved transiently depending on the fluidic resistance in the microfluidic device. Based on the transient behaviors of blood flows, the deformability of RBCs is quantified by evaluating three representative parameters, namely, minimum value of the average velocity of blood flow, clogging index, and delivered blood volume. The proposed method was applied to measure the deformability of blood samples consisting of homogeneous RBCs fixed with four different concentrations of glutaraldehyde solution (0%-0.23%). The proposed method was also employed to evaluate the deformability of blood samples partially mixed with normal RBCs and hardened RBCs. Thereafter, the deformability of RBCs infected by human malaria parasite Plasmodium falciparum was measured. As a result, the three parameters significantly varied, depending on the degree of deformability. In addition, the deformability measurement of blood samples was successfully completed in a short time (∼10 min). Therefore, the proposed method has significant potential in deformability measurement of blood samples containing hematological diseases with high throughput and precise detection of

  14. The mechanical properties of stored red blood cells measured by a convenient microfluidic approach combining with mathematic model.

    Science.gov (United States)

    Wang, Ying; You, Guoxing; Chen, Peipei; Li, Jianjun; Chen, Gan; Wang, Bo; Li, Penglong; Han, Dong; Zhou, Hong; Zhao, Lian

    2016-03-01

    The mechanical properties of red blood cells (RBCs) are critical to the rheological and hemodynamic behavior of blood. Although measurements of the mechanical properties of RBCs have been studied for many years, the existing methods, such as ektacytometry, micropipette aspiration, and microfluidic approaches, still have limitations. Mechanical changes to RBCs during storage play an important role in transfusions, and so need to be evaluated pre-transfusion, which demands a convenient and rapid detection method. We present a microfluidic approach that focuses on the mechanical properties of single cell under physiological shear flow and does not require any high-end equipment, like a high-speed camera. Using this method, the images of stretched RBCs under physical shear can be obtained. The subsequent analysis, combined with mathematic models, gives the deformability distribution, the morphology distribution, the normalized curvature, and the Young's modulus (E) of the stored RBCs. The deformability index and the morphology distribution show that the deformability of RBCs decreases significantly with storage time. The normalized curvature, which is defined as the curvature of the cell tail during stretching in flow, suggests that the surface charge of the stored RBCs decreases significantly. According to the mathematic model, which derives from the relation between shear stress and the adherent cells' extension ratio, the Young's moduli of the stored RBCs are also calculated and show significant increase with storage. Therefore, the present method is capable of representing the mechanical properties and can distinguish the mechanical changes of the RBCs during storage. The advantages of this method are the small sample needed, high-throughput, and easy-use, which make it promising for the quality monitoring of RBCs. PMID:27014397

  15. 近期微流控芯片疾病诊断技术的研究进展%Recent development of microfluidic diagnostic technologies

    Institute of Scientific and Technical Information of China (English)

    李海芳; 张倩云; 林金明

    2011-01-01

    Microfluidic devices exhibit a great promising development in clinical diagnosis and disease screening due to their advantages of precise controlling of fluid flow, requirement of miniamount sample, rapid reaction speed and convenient integration. In this paper, the improvements of microfluidic diagnostic technologies in recent years are reviewed. The applications and developments of on-chip disease marker detection, microfluidic cell selection and cell drug metabolism, and diagnostic micro-devices are discussed.%微流控芯片具有液流可控、样品消耗量小、反应速度快、易于集成化等特点,在临床诊断和疾病筛查领域具有广阔的发展前景.本文针对近年来微流控芯片技术在疾病诊断方面的最新研究进展,从疾病标志物检测、细胞筛选和药物代谢研究及疾病诊断微流控芯片装置的发展现状等方面概述其在疾病诊断方面的应用和发展.

  16. Microfluidic Amperometric Sensor for Analysis of Nitric Oxide in Whole Blood

    OpenAIRE

    Hunter, Rebecca A.; Privett, Benjamin J.; Henley, W. Hampton; Breed, Elise R.; Liang, Zhe; Mittal, Rohit; Yoseph, Benyam P.; McDunn, Jonathan E.; Eileen M Burd; Coopersmith, Craig M.; Ramsey, J. Michael; Schoenfisch, Mark H.

    2013-01-01

    Standard photolithographic techniques and a nitric oxide (NO) selective xerogel polymer were utilized to fabricate an amperometric NO microfluidic sensor with low background noise and the ability to analyze NO levels in small sample volumes (~250 μL). The sensor exhibited excellent analytical performance in phosphate buffered saline, including a NO sensitivity of 1.4 pA nM−1, a limit of detection (LOD) of 840 pM, and selectivity over nitrite, ascorbic acid, acetaminophen, uric acid, hydrogen ...

  17. A Turbidity Test Based Centrifugal Microfluidics Diagnostic System for Simultaneous Detection of HBV, HCV, and CMV

    Directory of Open Access Journals (Sweden)

    Hung-Cheng Chang

    2015-01-01

    Full Text Available This paper presents a LAMP- (loop-mediated isothermal amplification- based lab-on-disk optical system that allows the simultaneous detection of hepatitis B virus, hepatitis C virus, and cytomegalovirus. The various flow stages are controlled in the proposed system using different balance among centrifugal pumping, Coriolis pumping, and the capillary force. We have implemented a servo system for positioning and speed control for the heating and centrifugal pumping. We have also successfully employed a polymer light-emitting diode section for turbidity detection. The easy-to-use one-click system can perform diagnostics in less than 1 hour.

  18. Microfluidic Device

    Science.gov (United States)

    Tai, Yu-Chong (Inventor); Zheng, Siyang (Inventor); Lin, Jeffrey Chun-Hui (Inventor); Kasdan, Harvey L. (Inventor)

    2016-01-01

    Described herein are particular embodiments relating to a microfluidic device that may be utilized for cell sensing, counting, and/or sorting. Particular aspects relate to a microfabricated device that is capable of differentiating single cell types from dense cell populations. One particular embodiment relates a device and methods of using the same for sensing, counting, and/or sorting leukocytes from whole, undiluted blood samples.

  19. Postgenomics Diagnostics: Metabolomics Approaches to Human Blood Profiling

    OpenAIRE

    Trifonova, Oxana; Lokhov, Petr; Archakov, Alexander

    2013-01-01

    We live in exciting times with the prospects of postgenomics diagnostics. Metabolomics is a novel “omics” data-intensive science that is accelerating the development of postgenomics diagnostics, particularly with use of accessible peripheral tissue compartments. Metabolomics involves the study of a comprehensive set of low molecular weight substances (metabolites) present in biological systems. The metabolite profiles represent the molecular phenotype of biological systems and reflect the inf...

  20. Microfluidic bead-based multienzyme-nanoparticle amplification for detection of circulating tumor cells in the blood using quantum dots labels.

    Science.gov (United States)

    Zhang, He; Fu, Xin; Hu, Jiayi; Zhu, Zhenjun

    2013-05-24

    This study reports the development of a microfluidic bead-based nucleic acid sensor for sensitive detection of circulating tumor cells in blood samples using multienzyme-nanoparticle amplification and quantum dot labels. In this method, the microbeads functionalized with the capture probes and modified electron rich proteins were arrayed within a microfluidic channel as sensing elements, and the gold nanoparticles (AuNPs) functionalized with the horseradish peroxidases (HRP) and DNA probes were used as labels. Hence, two signal amplification approaches are integrated for enhancing the detection sensitivity of circulating tumor cells. First, the large surface area of Au nanoparticle carrier allows several binding events of HRP on each nanosphere. Second, enhanced mass transport capability inherent from microfluidics leads to higher capture efficiency of targets because continuous flow within micro-channel delivers fresh analyte solution to the reaction site which maintains a high concentration gradient differential to enhance mass transport. Based on the dual signal amplification strategy, the developed microfluidic bead-based nucleic acid sensor could discriminate as low as 5 fM (signal-to-noise (S/N)3) of synthesized carcinoembryonic antigen (CEA) gene fragments and showed a 1000-fold increase in detection limit compared to the off-chip test. In addition, using spiked colorectal cancer cell lines (HT29) in the blood as a model system, the detection limit of this chip-based approach was found to be as low as 1 HT29 in 1 mL blood sample. This microfluidic bead-based nucleic acid sensor is a promising platform for disease-related nucleic acid molecules at the lowest level at their earliest incidence. PMID:23663673

  1. Going beyond 20 μm-sized channels for studying red blood cell phase separation in microfluidic bifurcations.

    Science.gov (United States)

    Roman, Sophie; Merlo, Adlan; Duru, Paul; Risso, Frédéric; Lorthois, Sylvie

    2016-05-01

    Despite the development of microfluidics, experimental challenges are considerable for achieving a quantitative study of phase separation, i.e., the non-proportional distribution of Red Blood Cells (RBCs) and suspending fluid, in microfluidic bifurcations with channels smaller than 20 μm. Yet, a basic understanding of phase separation in such small vessels is needed for understanding the coupling between microvascular network architecture and dynamics at larger scale. Here, we present the experimental methodologies and measurement techniques developed for that purpose for RBC concentrations (tube hematocrits) ranging between 2% and 20%. The maximal RBC velocity profile is directly measured by a temporal cross-correlation technique which enables to capture the RBC slip velocity at walls with high resolution, highlighting two different regimes (flat and more blunted ones) as a function of RBC confinement. The tube hematocrit is independently measured by a photometric technique. The RBC and suspending fluid flow rates are then deduced assuming the velocity profile of a Newtonian fluid with no slip at walls for the latter. The accuracy of this combination of techniques is demonstrated by comparison with reference measurements and verification of RBC and suspending fluid mass conservation at individual bifurcations. The present methodologies are much more accurate, with less than 15% relative errors, than the ones used in previous in vivo experiments. Their potential for studying steady state phase separation is demonstrated, highlighting an unexpected decrease of phase separation with increasing hematocrit in symmetrical, but not asymmetrical, bifurcations and providing new reference data in regimes where in vitro results were previously lacking. PMID:27190568

  2. Automatic disease screening method using image processing for dried blood microfluidic drop stain pattern recognition.

    Science.gov (United States)

    Sikarwar, Basant S; Roy, Mukesh; Ranjan, Priya; Goyal, Ayush

    2016-07-01

    This paper examines programmed automatic recognition of infection from samples of dried stains of micro-scale drops of patient blood. This technique has the upside of being low-cost and less-intrusive and not requiring puncturing the patient with a needle for drawing blood, which is especially critical for infants and the matured. It also does not require expensive pathological blood test laboratory equipment. The method is shown in this work to be successful for ailment identification in patients suffering from tuberculosis and anaemia. Illness affects the physical properties of blood, which thus influence the samples of dried micro-scale blood drop stains. For instance, if a patient has a severe drop in platelet count, which is often the case of dengue or malaria patients, the blood's physical property of viscosity drops substantially, i.e. the blood is thinner. Thus, the blood micro-scale drop stain samples can be utilised for diagnosing maladies. This paper presents programmed automatic examination of the dried micro-scale drop blood stain designs utilising an algorithm based on pattern recognition. The samples of micro-scale blood drop stains of ordinary non-infected people are clearly recognisable as well as the samples of micro-scale blood drop stains of sick people, due to key distinguishing features. As a contextual analysis, the micro-scale blood drop stains of patients infected with tuberculosis have been contrasted with the micro-scale blood drop stains of typical normal healthy people. The paper dives into the fundamental flow mechanics behind how the samples of the dried micro-scale blood drop stain is shaped. What has been found is a thick ring like feature in the dried micro-scale blood drop stains of non-ailing people and thin shape like lines in the dried micro-scale blood drop stains of patients with anaemia or tuberculosis disease. The ring like feature at the periphery is caused by an outward stream conveying suspended particles to the edge

  3. Microfluidic bead-based multienzyme-nanoparticle amplification for detection of circulating tumor cells in the blood using quantum dots labels

    International Nuclear Information System (INIS)

    Graphical abstract: A microfluidic beads-based nucleic acid sensor for sensitive detection of circulating tumor cells (CTCs) in the blood using multienzyme-nanoparticle amplification and quantum dots labels was developed. The chip-based CTCs analysis could detect reverse transcription-polymerase chain reaction (RT-PCR) products of tumor cell as low as 1 tumor cell (e.g. CEA expressing cell) in 1 mL blood sample. This microfluidic beads-based nucleic acid sensor is a promising platform for disease-related nucleic acid molecules at the lowest level at their earliest incidence. -- Highlights: •Combination of microfluidic bead-based platform and enzyme–probe–AuNPs is proposed. •The developed nucleic acid sensor could respond to 5 fM of tumor associated DNA. •Microfluidic platform and multienzyme-labeled AuNPs greatly enhanced sensitivity. •The developed nucleic acid sensor could respond to RT-PCR products of tumor cell as low as 1 tumor cell in 1 mL blood sample. •We report a sensitive nucleic acid sensor for detection of circulating tumor cells. -- Abstract: This study reports the development of a microfluidic bead-based nucleic acid sensor for sensitive detection of circulating tumor cells in blood samples using multienzyme-nanoparticle amplification and quantum dot labels. In this method, the microbeads functionalized with the capture probes and modified electron rich proteins were arrayed within a microfluidic channel as sensing elements, and the gold nanoparticles (AuNPs) functionalized with the horseradish peroxidases (HRP) and DNA probes were used as labels. Hence, two signal amplification approaches are integrated for enhancing the detection sensitivity of circulating tumor cells. First, the large surface area of Au nanoparticle carrier allows several binding events of HRP on each nanosphere. Second, enhanced mass transport capability inherent from microfluidics leads to higher capture efficiency of targets because continuous flow within micro

  4. Microfluidic bead-based multienzyme-nanoparticle amplification for detection of circulating tumor cells in the blood using quantum dots labels

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, He, E-mail: mzhang_he@126.com; Fu, Xin; Hu, Jiayi; Zhu, Zhenjun

    2013-05-24

    Graphical abstract: A microfluidic beads-based nucleic acid sensor for sensitive detection of circulating tumor cells (CTCs) in the blood using multienzyme-nanoparticle amplification and quantum dots labels was developed. The chip-based CTCs analysis could detect reverse transcription-polymerase chain reaction (RT-PCR) products of tumor cell as low as 1 tumor cell (e.g. CEA expressing cell) in 1 mL blood sample. This microfluidic beads-based nucleic acid sensor is a promising platform for disease-related nucleic acid molecules at the lowest level at their earliest incidence. -- Highlights: •Combination of microfluidic bead-based platform and enzyme–probe–AuNPs is proposed. •The developed nucleic acid sensor could respond to 5 fM of tumor associated DNA. •Microfluidic platform and multienzyme-labeled AuNPs greatly enhanced sensitivity. •The developed nucleic acid sensor could respond to RT-PCR products of tumor cell as low as 1 tumor cell in 1 mL blood sample. •We report a sensitive nucleic acid sensor for detection of circulating tumor cells. -- Abstract: This study reports the development of a microfluidic bead-based nucleic acid sensor for sensitive detection of circulating tumor cells in blood samples using multienzyme-nanoparticle amplification and quantum dot labels. In this method, the microbeads functionalized with the capture probes and modified electron rich proteins were arrayed within a microfluidic channel as sensing elements, and the gold nanoparticles (AuNPs) functionalized with the horseradish peroxidases (HRP) and DNA probes were used as labels. Hence, two signal amplification approaches are integrated for enhancing the detection sensitivity of circulating tumor cells. First, the large surface area of Au nanoparticle carrier allows several binding events of HRP on each nanosphere. Second, enhanced mass transport capability inherent from microfluidics leads to higher capture efficiency of targets because continuous flow within micro

  5. Single-Cell Isolation of Circulating Tumor Cells from Whole Blood by Lateral Magnetophoretic Microseparation and Microfluidic Dispensing.

    Science.gov (United States)

    Kim, Jinho; Cho, Hyungseok; Han, Song-I; Han, Ki-Ho

    2016-05-01

    This paper introduces a single-cell isolation technology for circulating tumor cells (CTCs) using a microfluidic device (the "SIM-Chip"). The SIM-Chip comprises a lateral magnetophoretic microseparator and a microdispenser as a two-step cascade platform. First, CTCs were enriched from whole blood by the lateral magnetophoretic microseparator based on immunomagnetic nanobeads. Next, the enriched CTCs were electrically identified by single-cell impedance cytometer and isolated as single cells using the microshooter. Using 200 μL of whole blood spiked with 50 MCF7 breast cancer cells, the analysis demonstrated that the single-cell isolation efficiency of the SIM-Chip was 82.4%, and the purity of the isolated MCF7 cells with respect to WBCs was 92.45%. The data also showed that the WBC depletion rate of the SIM-Chip was 2.5 × 10(5) (5.4-log). The recovery rates were around 99.78% for spiked MCF7 cells ranging in number from 10 to 90. The isolated single MCF7 cells were intact and could be used for subsequent downstream genetic assays, such as RT-PCR. Single-cell culture evaluation of the proliferation of MCF7 cells isolated by the SIM-Chip showed that 84.1% of cells at least doubled in 5 days. Consequently, the SIM-Chip could be used for single-cell isolation of rare target cells from whole blood with high purity and recovery without cell damage. PMID:27093098

  6. Comparison of roll-to-roll replication approaches for microfluidic and optical functions in lab-on-a-chip diagnostic devices

    Science.gov (United States)

    Brecher, Christian; Baum, Christoph; Bastuck, Thomas

    2015-03-01

    Economically advantageous microfabrication technologies for lab-on-a-chip diagnostic devices substituting commonly used glass etching or injection molding processes are one of the key enablers for the emerging market of microfluidic devices. On-site detection in fields of life sciences, point of care diagnostics and environmental analysis requires compact, disposable and highly functionalized systems. Roll-to-roll production as a high volume process has become the emerging fabrication technology for integrated, complex high technology products within recent years (e.g. fuel cells). Differently functionalized polymer films enable researchers to create a new generation of lab-on-a-chip devices by combining electronic, microfluidic and optical functions in multilayer architecture. For replication of microfluidic and optical functions via roll-to-roll production process competitive approaches are available. One of them is to imprint fluidic channels and optical structures of micro- or nanometer scale from embossing rollers into ultraviolet (UV) curable lacquers on polymer substrates. Depending on dimension, shape and quantity of those structures there are alternative manufacturing technologies for the embossing roller. Ultra-precise diamond turning, electroforming or casting polymer materials are used either for direct structuring or manufacturing of roller sleeves. Mastering methods are selected for application considering replication quality required and structure complexity. Criteria for the replication quality are surface roughness and contour accuracy. Structure complexity is evaluated by shapes producible (e.g. linear, circular) and aspect ratio. Costs for the mastering process and structure lifetime are major cost factors. The alternative replication approaches are introduced and analyzed corresponding to the criteria presented. Advantages and drawbacks of each technology are discussed and exemplary applications are presented.

  7. Challenges in the Use of Compact Disc-Based Centrifugal Microfluidics for Healthcare Diagnostics at the Extreme Point of Care

    Directory of Open Access Journals (Sweden)

    Jordon Gilmore

    2016-03-01

    Full Text Available Since its inception, Compact Disc (CD-based centrifugal microfluidic technology has drawn a great deal of interest within research communities due to its potential use in biomedical applications. The technology has been referred to by different names, including compact-disc microfluidics, lab-on-a-disk, lab-on-a-CD and bio-disk. This paper critically reviews the state-of-the-art in CD-based centrifugal microfluidics devices and attempts to identify the challenges that, if solved, would enable their use in the extreme point of care. Sample actuation, manufacturing, reagent storage and implementation, target multiplexing, bio-particle detection, required hardware and system disposal, and sustainability are the topics of focus.

  8. In Vitro Blood-Brain Barrier Models-An Overview of Established Models and New Microfluidic Approaches.

    Science.gov (United States)

    Wolff, Anette; Antfolk, Maria; Brodin, Birger; Tenje, Maria

    2015-09-01

    The societal need for new central nervous system (CNS) medicines is substantial, because of the global increase in life expectancy and the accompanying increase in age-related CNS diseases. Low blood-brain barrier (BBB) permeability has been one of the major causes of failure for new CNS drug candidates. There has therefore been a great interest in cell models, which mimic BBB permeation properties. In this review, we present an overview of the performance of monocultured, cocultured, and triple-cultured primary cells and immortalized cell lines, including key parameters such as transendothelial electrical resistance values, permeabilities of paracellular flux markers, and expression of BBB-specific marker proteins. Microfluidic systems are gaining ground as a new automated technical platform for cell culture and systematic analysis. The performance of these systems was compared with current state-of-the-art models and it was noted that, although they show great promise, these systems have not yet reached beyond the proof-of-concept stage. In general, it was found that there were large variations in experimental protocols, BBB phenotype markers, and paracellular flux markers used. It is the author's opinion that the field may benefit greatly from developing standardized methodologies and initiating collaborative efforts on optimizing culture protocols. PMID:25630899

  9. A microfluidic system enabling Raman measurements of the oxygenation cycle in single optically trapped red blood cells.

    Science.gov (United States)

    Ramser, Kerstin; Enger, Jonas; Goksör, Mattias; Hanstorp, Dag; Logg, Katarina; Käll, Mikael

    2005-04-01

    Using a lab-on-a-chip approach we demonstrate the possibility of selecting a single cell with certain properties and following its dynamics after an environmental stimulation in real time using Raman spectroscopy. This is accomplished by combining a micro Raman set-up with optical tweezers and a microfluidic system. The latter gives full control over the media surrounding the cell, and it consists of a pattern of channels and reservoirs defined by electron beam lithography that is moulded into rubber silicon (PDMS). Different buffers can be transported through the channels using electro-osmotic flow, while the resonance Raman response of an optically trapped red blood cell (RBC) is simultaneously registered. This makes it possible to monitor the oxygenation cycle of the cell in real time and to investigate effects like photo-induced chemistry caused by the illumination. The experimental set-up has high potential for in vivo monitoring of cellular drug response using a variety of spectroscopic probes. PMID:15791341

  10. Microfluidic Leukocyte Isolation for Gene Expression Analysis in Critically Ill Hospitalized Patients

    Science.gov (United States)

    Russom, Aman; Sethu, Palaniappan; Irimia, Daniel; Mindrinos, Michael N.; Calvano, Steve E.; Garcia, Iris; Finnerty, Celeste; Tannahill, Cynthia; Abouhamze, Amer; Wilhelmy, Julie; López, M. Cecilia; Baker, Henry V.; Herndon, David N.; Lowry, Stephen F.; Maier, Ronald V.; Davis, Ronald W.; Moldawer, Lyle L.; Tompkins, Ronald G.; Toner, Mehmet

    2014-01-01

    BACKGROUND Microarray technology is becoming a powerful tool for diagnostic, therapeutic, and prognostic applications. There is at present no consensus regarding the optimal technique to isolate nucleic acids from blood leukocyte populations for subsequent expression analyses. Current collection and processing techniques pose significant challenges in the clinical setting. Here, we report the clinical validation of a novel microfluidic leukocyte nucleic acid isolation technique for gene expression analysis from critically ill, hospitalized patients that can be readily used on small volumes of blood. METHODS We processed whole blood from hospitalized patients after burn injury and severe blunt trauma according to the microfluidic and standard macroscale leukocyte isolation protocol. Side-by-side comparison of RNA quantity, quality, and genome-wide expression patterns was used to clinically validate the microfluidic technique. RESULTS When the microfluidic protocol was used for processing, sufficient amounts of total RNA were obtained for genome-wide expression analysis from 0.5 mL whole blood. We found that the leukocyte expression patterns from samples processed using the 2 protocols were concordant, and there was less variability introduced as a result of harvesting method than there existed between individuals. CONCLUSIONS The novel microfluidic approach achieves leukocyte isolation in <25 min, and the quality of nucleic acids and genome expression analysis is equivalent to or surpasses that obtained from macroscale approaches. Microfluidics can significantly improve the isolation of blood leukocytes for genomic analyses in the clinical setting. PMID:18375483

  11. Punch Card Programmable Microfluidics

    OpenAIRE

    George Korir; Manu Prakash

    2014-01-01

    Small volume fluid handling in single and multiphase microfluidics provides a promising strategy for efficient bio-chemical assays, low-cost point-of-care diagnostics and new approaches to scientific discoveries. However multiple barriers exist towards low-cost field deployment of programmable microfluidics. Incorporating multiple pumps, mixers and discrete valve based control of nanoliter fluids and droplets in an integrated, programmable manner without additional required external component...

  12. Investigations of significance of blood smear results in diagnostics of infectious and parasitic diseases in dogs

    Directory of Open Access Journals (Sweden)

    Potkonjak Aleksandar

    2010-01-01

    Full Text Available The microscopic examination of stained smears of peripheral blood is of vital significance in the speedy diagnostics of infectious and parasitic diseases, in particular during the stage of infection when the cause is present in the blood, or blood cells. It is sometimes possible to make a definitive diagnosis of an infectious or parasitic disease following an examination of a stained smear of the peripheral blood. Since microscopic examinations of a peripheral blood smear are applied increasingly rarely in clinical practice, due to the development of other methods for the diagnostics of infectious and parasitic diseases in dogs, as well as the lack of knowledge of the morphology of the numerous causes that can be present in the blood, we carried out an investigation into the presence and spread of infections whose causes can be present in dog blood. The investigations covered 100 dogs from which peripheral blood smears were taken and then stained with a Giemsa solution according to the standard protocol and examined under a microscope with an immersion lens. The examination of peripheral blood smears stained according to Giemsa resulted in the identification of the presence of an Ehrlichia spp. morula in a neutrophil granulocyte in one dog. The presence of hemotropic mycoplasmas was established in erythrocytes of eleven dogs, while the presence of the protozoa Babesia canis in erythrocytes was identified in five dogs included in the investigations. A microscopic examination of dog peripheral blood smears stained according to Giemsa was shown as a speedy, practical, simple, and inexpensive method for making a definitive etiological diagnosis of these infections, and it should be included regularly in standard protocols for the diagnostics of infectious and parasitic diseases.

  13. Rapid organism identification from Bactec NR blood culture media in a diagnostic microbiology laboratory.

    OpenAIRE

    Claxton, P M; Masterton, R G

    1994-01-01

    AIMS--To evaluate rapid organism identification on positive blood culture Bactec NR media (phial types 26, 27, 42 and 17), and to assess the usefulness of these procedures in a diagnostic microbiology laboratory. METHODS--Two hundred and sixty, first positive, blood culture bottles from individual patients were tested by rapid identification methods selected on the basis of Gram film organism morphology. Tube coagulase and latex agglutination were applied to presumptive staphylococci; latex a...

  14. Blood CEA levels for detecting recurrent colorectal cancer: A Diagnostic Test Accuracy Review.

    OpenAIRE

    Nicholson, BD; Shinkins, B.; Pathiraja, I; Roberts, NW; James, T; Mallett, S.; Perera, R; Primrose, JN; Mant, D

    2015-01-01

    Background Testing for carcino-embryonic antigen (CEA) in the blood is a recommended part of follow-up to detect recurrence of colorectal cancer following primary curative treatment. There is substantial clinical variation in the cut-off level applied to trigger further investigation. Objectives To determine the diagnostic performance of different blood CEA levels in identifying people with colorectal cancer recurrence in order to inform clinical practice. Search methods W...

  15. Digital Microfluidics Sample Analyzer

    Science.gov (United States)

    Pollack, Michael G.; Srinivasan, Vijay; Eckhardt, Allen; Paik, Philip Y.; Sudarsan, Arjun; Shenderov, Alex; Hua, Zhishan; Pamula, Vamsee K.

    2010-01-01

    Three innovations address the needs of the medical world with regard to microfluidic manipulation and testing of physiological samples in ways that can benefit point-of-care needs for patients such as premature infants, for which drawing of blood for continuous tests can be life-threatening in their own right, and for expedited results. A chip with sample injection elements, reservoirs (and waste), droplet formation structures, fluidic pathways, mixing areas, and optical detection sites, was fabricated to test the various components of the microfluidic platform, both individually and in integrated fashion. The droplet control system permits a user to control droplet microactuator system functions, such as droplet operations and detector operations. Also, the programming system allows a user to develop software routines for controlling droplet microactuator system functions, such as droplet operations and detector operations. A chip is incorporated into the system with a controller, a detector, input and output devices, and software. A novel filler fluid formulation is used for the transport of droplets with high protein concentrations. Novel assemblies for detection of photons from an on-chip droplet are present, as well as novel systems for conducting various assays, such as immunoassays and PCR (polymerase chain reaction). The lab-on-a-chip (a.k.a., lab-on-a-printed-circuit board) processes physiological samples and comprises a system for automated, multi-analyte measurements using sub-microliter samples of human serum. The invention also relates to a diagnostic chip and system including the chip that performs many of the routine operations of a central labbased chemistry analyzer, integrating, for example, colorimetric assays (e.g., for proteins), chemiluminescence/fluorescence assays (e.g., for enzymes, electrolytes, and gases), and/or conductometric assays (e.g., for hematocrit on plasma and whole blood) on a single chip platform.

  16. The diagnostic value of cardiac blood pool imaging in cardiomyopathy

    International Nuclear Information System (INIS)

    Twenty-two normal controls and thirty-three patients with dilated and hypertrophic cardiomyopathy were examined by multigated cardiac imaging and phase analysis. The imaging traits of hypertrophic ones displayed thicken septal wall. The differences of synchronization of ventricular systolic function between hypertrophic ones and normal were statistically significant (P < 0.01). The imaging features of dilated cardiomyopathy showed that ventricular wall motion was seriously hypokinitic or akinitic and left ventricule enlarged abnormally. The function and synchronization of ventricular systole in dilated ones were worse than these in the hypertrophic (P < 0.01). These data suggest that the cardiac blood pool images can diagnose and differentiate the hypertrophic from dilated cardiomyopathy

  17. Blood lactate diagnostics in exercise testing and training.

    Science.gov (United States)

    Beneke, Ralph; Leithäuser, Renate M; Ochentel, Oliver

    2011-03-01

    A link between lactate and muscular exercise was seen already more than 200 years ago. The blood lactate concentration (BLC) is sensitive to changes in exercise intensity and duration. Multiple BLC threshold concepts define different points on the BLC power curve during various tests with increasing power (INCP). The INCP test results are affected by the increase in power over time. The maximal lactate steady state (MLSS) is measured during a series of prolonged constant power (CP) tests. It detects the highest aerobic power without metabolic energy from continuing net lactate production, which is usually sustainable for 30 to 60 min. BLC threshold and MLSS power are highly correlated with the maximum aerobic power and athletic endurance performance. The idea that training at threshold intensity is particularly effective has no evidence. Three BLC-orientated intensity domains have been established: (1) training up to an intensity at which the BLC clearly exceeds resting BLC, light- and moderate-intensity training focusing on active regeneration or high-volume endurance training (Intensity MLSS). High-performance endurance athletes combining very high training volume with high aerobic power dedicate 70 to 90% of their training to intensity domain 1 (Intensity < Threshold) in order to keep glycogen homeostasis within sustainable limits. PMID:21487146

  18. Effect of cationic polyelectrolytes on the performance of paper diagnostics for blood typing.

    Science.gov (United States)

    McLiesh, Heather; Sharman, Scot; Garnier, Gil

    2015-09-01

    We investigated the effect that two common types of cationic polyelectrolytes used in papermaking might have on the performance of paper diagnostics using blood typing as an example. The results were analyzed in terms of red blood cells (RBC) retention and antibody-antigen specificity. Two questions were addressed: (1) can poly(amido-amine) epichlorohydrin (PAE) typically used for paper wet strength affect the diagnostic performance? (2) can high molecular weight cationic polyacrylamide (CPAM) employed as retention aid enhance or affect the selectivity and sensitivity of paper diagnostics? A series of paper varying in type of fibers and drying process were constructed with PAE and tested for blood typing performance. Residual PAE has no significant effect on blood typing paper diagnostics under normal conditions. Positives are unaffected with PAE, while negatives lose slight sharpness as some RBCs are unselectively retained. CPAM, the most common retention aid, can also be used to retain cells and biomolecules on paper. Paper towel was treated with CPAM solutions varying in polymer concentration and charge density and tested for blood typing. We found that CPAM dried on paper can retain RBC. CPAM affects the negative tests by retaining non-specifically individual RBC on fibers. RBC retention increases non-linearly with the CPAM charge density and concentration. As expected, wet CPAM retain RBCs at concentrations higher than 0.1wt%. As paper diagnostics are becoming a reality, more realistic papers than the Whatman filter paper will be engineered. This study provides guidance on how best use the required polymeric wet-strength and retention agents. PMID:26101819

  19. Punch Card Programmable Microfluidics

    CERN Document Server

    Korir, George

    2014-01-01

    Small volume fluid handling in single and multiphase microfluidics provides a promising strategy for efficient bio-chemical assays, low-cost point-of-care diagnostics and new approaches to scientific discoveries. However multiple barriers exist towards low-cost field deployment of programmable microfluidics. Incorporating multiple pumps, mixers and discrete valve based control of nanoliter fluids and droplets in an integrated, programmable manner without additional required external components has remained elusive. Combining the idea of punch card programming with arbitrary fluid control, here we describe a self-contained, hand-crank powered, multiplex and robust programmable microfluidic platform. A paper tape encodes information as a series of punched holes. A mechanical reader/actuator reads these paper tapes and correspondingly executes a series of operations onto a microfluidic chip coupled to the platform in a plug-and-play fashion. Enabled by the complexity of codes that can be represented by a series ...

  20. An assessment of various blood collection and transfer methods used for malaria rapid diagnostic tests

    Directory of Open Access Journals (Sweden)

    Baik Fred

    2007-11-01

    Full Text Available Abstract Background Four blood collection and transfer devices commonly used for malaria rapid diagnostic tests (RDTs were assessed for their consistency, accuracy and ease of use in the hands of laboratory technicians and village health workers. Methods Laboratory technicians and village health workers collected blood from a finger prick using each device in random order, and deposited the blood either on filter paper or into a suitable casette-type RDT. Consistency and accuracy of volume delivered was determined by comparing the measurements of the resulting blood spots/heights with the measurements of laboratory-prepared pipetted standard volumes. The effect of varying blood volumes on RDT sensitivity and ease of use was also observed. Results There was high variability in blood volume collected by the devices, with the straw and the loop, the most preferred devices, usually transferring volumes greater than intended, while the glass capillary tube and the plastic pipette transferring less volume than intended or none at all. Varying the blood volume delivered to RDTs indicated that this variation is critical to RDT sensitivity only when the transferred volume is very low. Conclusion None of the blood transfer devices assessed performed consistently well. Adequate training on their use is clearly necessary, with more development efforts for improved designs to be used by remote health workers, in mind.

  1. Investigation of opportunities of the optical non-invasive diagnostics method for the blood sugar control

    Science.gov (United States)

    Lastovskaia, Elena A.; Gorbunova, Elena V.; Chertov, Aleksandr N.; Korotaev, Valery V.

    2015-03-01

    The relevance of noninvasive method for determining the blood sugar is caused by necessity of regular monitoring of glucose levels in diabetic patients blood. Traditional invasive method is painful, because it requires a finger pricking. Despite the active studies in the field of non-invasive medical diagnostics, to date the painless and inexpensive instrument for blood sugar control for personal use doesn't exist. It's possible to measure the concentration of glucose in the blood with help of spectrophotometry method. It consists of registering and analyzing the spectral characteristics of the radiation which missed, reflected or absorbed by the object. The authors proposed a measuring scheme for studying the spectral characteristics of the radiation, missed by earlobe. Ultra-violet, visible and near infrared spectral ranges are considered. The paper presents the description of construction and working principles of the proposed special retaining clip and results of experiment with real patient.

  2. Microfluidics for medical applications

    NARCIS (Netherlands)

    Berg, van den Albert; Segerink, Loes

    2015-01-01

    Lab-on-a-chip devices for point of care diagnostics have been present in clinics for several years now. Alongside their continual development, research is underway to bring the organs and tissue on-a-chip to the patient, amongst other medical applications of microfluidics. This book provides the re

  3. Black blood MRI has diagnostic and prognostic value in the assessment of patients with pulmonary hypertension

    International Nuclear Information System (INIS)

    Double inversion recovery (DIR) ''black blood'' MRI suppresses the signal from flowing blood, slow flowing blood causes incomplete suppression resulting in pulmonary blood flow artefact (PFA). This study examines the diagnostic utility and prognostic value of a PFA scoring system in a mixed cohort of patients with pulmonary hypertension (PH). DIR-MRI images were reviewed for 233 patients referred with suspected PH who underwent right heart catheterisation (RHC) within 48 h of MR. The degree of PFA was visually scored in all patients from 0 to 5 (0 = absent, 1 = segmental, 2 = lobar, 3 = distal main, 4 = proximal main and 5 = trunk). Pulmonary artery (PA), aorta (Ao), and PA main branch diameters were measured from which PA/Ao ratios and mean PA branch diameters (MPAB) were calculated. PFA >1 demonstrated high sensitivity (86%) and specificity (85%) for the diagnosis PH in our mixed patient cohort. A good correlation was found with PFA and haemodynamic parameters, PVR (r = 0.70), mPAP (r = 0.65) and CI (r = -0.53). PFA predicted mortality (P = 0.005) during the mean follow-up for 19 months. PFA scoring demonstrated good inter-observer agreement (k = 0.83). PFA scoring is of diagnostic and prognostic value in the assessment of patients with suspected PH. and is a predictor of mortality. (orig.)

  4. Black blood MRI has diagnostic and prognostic value in the assessment of patients with pulmonary hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Swift, Andrew J.; Marshall, Helen; Wild, Jim M. [Cardiovascular Biomedical Research Unit, National Institute of Health Research, Sheffield (United Kingdom); University of Sheffield, Academic Unit of Radiology, Sheffield (United Kingdom); Rajaram, Smitha; Capener, Dave [University of Sheffield, Academic Unit of Radiology, Sheffield (United Kingdom); Condliffe, Robin; Elliot, Charlie A.; Kiely, David G. [Cardiovascular Biomedical Research Unit, National Institute of Health Research, Sheffield (United Kingdom); Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield (United Kingdom); Hill, Catherine; Davies, Christine [Sheffield Teaching Hospitals NHS Foundation Trust, Department of Radiology, Sheffield (United Kingdom); Hurdman, Judith [Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield (United Kingdom)

    2012-03-15

    Double inversion recovery (DIR) ''black blood'' MRI suppresses the signal from flowing blood, slow flowing blood causes incomplete suppression resulting in pulmonary blood flow artefact (PFA). This study examines the diagnostic utility and prognostic value of a PFA scoring system in a mixed cohort of patients with pulmonary hypertension (PH). DIR-MRI images were reviewed for 233 patients referred with suspected PH who underwent right heart catheterisation (RHC) within 48 h of MR. The degree of PFA was visually scored in all patients from 0 to 5 (0 = absent, 1 = segmental, 2 = lobar, 3 = distal main, 4 = proximal main and 5 = trunk). Pulmonary artery (PA), aorta (Ao), and PA main branch diameters were measured from which PA/Ao ratios and mean PA branch diameters (MPAB) were calculated. PFA >1 demonstrated high sensitivity (86%) and specificity (85%) for the diagnosis PH in our mixed patient cohort. A good correlation was found with PFA and haemodynamic parameters, PVR (r = 0.70), mPAP (r = 0.65) and CI (r = -0.53). PFA predicted mortality (P = 0.005) during the mean follow-up for 19 months. PFA scoring demonstrated good inter-observer agreement (k = 0.83). PFA scoring is of diagnostic and prognostic value in the assessment of patients with suspected PH. and is a predictor of mortality. (orig.)

  5. Microfluidics for medical applications

    OpenAIRE

    Berg, van den, T.J.T.P.; Segerink, Loes

    2015-01-01

    Lab-on-a-chip devices for point of care diagnostics have been present in clinics for several years now. Alongside their continual development, research is underway to bring the organs and tissue on-a-chip to the patient, amongst other medical applications of microfluidics. This book provides the reader with a comprehensive review of the latest developments in the application of microfluidics to medicine and is divided into three main sections. The first part of the book discusses the state-of...

  6. Comparison of production methods of a spiral inertial microfluidic cell separation device

    Science.gov (United States)

    Robinson, Mitchell; Marks, Haley; Coté, Gerard L.

    2016-03-01

    From the miniaturization of large sample processing machines to the creation of handheld point-of-care devices, microfluidics has the potential to be a powerful tool in the advancement of diagnostic technologies. Here, we compare different prototyping modalities towards the generation of an inertial microfluidic blood filter: i.e. a 'centrifuge-on-a-chip'. While photolithography is currently the method of choice for soft lithography mold fabrication, offering high design fidelity, we believe simpler methods, such as milling or 3D printing, will soon become equally viable options in the field of microfluidic device fabrication. Three modalities for optofluidic PDMS chip fabrication were compared: micromachining, 3D printing, and SU8 photolithography. The filtration efficiency of the chips were tested with whole blood and compared spectroscopically by monitoring the outlet absorbance at the 540 nm peak intrinsic to oxyhemoglobin at the outlet of each filter chip.

  7. Is intrapartum fetal blood sampling a gold standard diagnostic tool for fetal distress?

    Science.gov (United States)

    Mahendru, Amita A; Lees, Christoph C

    2011-06-01

    Developed in 1960s, cardiotocography is a screening test and fetal blood sampling (FBS) is an adjunctive, diagnostic technique to detect fetal hypoxia. A fetal blood sample pH value of less than 7.20 has a higher specificity than a pathological CTG to predict low Apgar score at 1 min. Though with a pathological CTG and despite a normal FBS pH value the risk of delivering a hypoxic infant is 30-50%, FBS has assumed considerable importance in purportedly reducing unnecessary obstetric intervention. The evidence for this is weak: the use of FBS with CTG has been shown to reduce operative vaginal deliveries though not Caesarean sections due to fetal distress. There is no difference in the umbilical artery pH at delivery with the use of intermittent FBS with CTG compared to CTG alone. FBS is an invasive procedure: obtaining an adequate blood sample is often difficult and the pH results are affected by handling of the sample, aerobic contamination and processing. Validation of intrapartum FBS requires that the pH and other values obtained are compared to a 'gold standard' technique. Although FBS has been compared to other tests such as scalp lactate, pulse oximetry, fetal ECG waveform analysis, and central haemodynamics in labouring rhesus monkeys, none of these can be considered as 'gold standard'. In the light of the existing evidence, the role of intrapartum FBS as a gold standard diagnostic technique is unproven. PMID:21300427

  8. Sensitive KIT D816V mutation analysis of blood as a diagnostic test in mastocytosis

    DEFF Research Database (Denmark)

    Kielsgaard Kristensen, Thomas; Vestergaard, Hanne; Bindslev-Jensen, Carsten; Møller, Michael Boe; Broesby-Olsen, Sigurd

    2014-01-01

    The recent progress in sensitive KIT D816V mutation analysis suggests that mutation analysis of peripheral blood (PB) represents a promising diagnostic test in mastocytosis. However, there is a need for systematic assessment of the analytical sensitivity and specificity of the approach in order to...... establish its value in clinical use. We therefore evaluated sensitive KIT D816V mutation analysis of PB as a diagnostic test in an entire case-series of adults with mastocytosis. We demonstrate for the first time that by using a sufficiently sensitive KIT D816V mutation analysis, it is possible to detect...... the mutation in PB in nearly all adult mastocytosis patients. The mutation was detected in PB in 78 of 83 systemic mastocytosis (94%) and 3 of 4 cutaneous mastocytosis patients (75%). The test was 100% specific as determined by analysis of clinically relevant control patients who all tested negative...

  9. Biomarkers in schizophrenia: A focus on blood based diagnostics and theranostics.

    Science.gov (United States)

    Lai, Chi-Yu; Scarr, Elizabeth; Udawela, Madhara; Everall, Ian; Chen, Wei J; Dean, Brian

    2016-03-22

    Identifying biomarkers that can be used as diagnostics or predictors of treatment response (theranostics) in people with schizophrenia (Sz) will be an important step towards being able to provide personalized treatment. Findings from the studies in brain tissue have not yet been translated into biomarkers that are practical in clinical use because brain biopsies are not acceptable and neuroimaging techniques are expensive and the results are inconclusive. Thus, in recent years, there has been search for blood-based biomarkers for Sz as a valid alternative. Although there are some encouraging preliminary data to support the notion of peripheral biomarkers for Sz, it must be acknowledged that Sz is a complex and heterogeneous disorder which needs to be further dissected into subtype using biological based and clinical markers. The scope of this review is to critically examine published blood-based biomarker of Sz, focusing on possible uses for diagnosis, treatment response, or their relationship with schizophrenia-associated phenotype. We sorted the studies into six categories which include: (1) brain-derived neurotrophic factor; (2) inflammation and immune function; (3) neurochemistry; (4) oxidative stress response and metabolism; (5) epigenetics and microRNA; and (6) transcriptome and proteome studies. This review also summarized the molecules which have been conclusively reported as potential blood-based biomarkers for Sz in different blood cell types. Finally, we further discusses the pitfall of current blood-based studies and suggest that a prediction model-based, Sz specific, blood oriented study design as well as standardize blood collection conditions would be useful for Sz biomarker development. PMID:27014601

  10. SPECT Myocardial Blood Flow Quantitation Concludes Equivocal Myocardial Perfusion SPECT Studies to Increase Diagnostic Benefits.

    Science.gov (United States)

    Chen, Lung-Ching; Lin, Chih-Yuan; Chen, Ing-Jou; Ku, Chi-Tai; Chen, Yen-Kung; Hsu, Bailing

    2016-01-01

    Recently, myocardial blood flow quantitation with dynamic SPECT/CT has been reported to enhance the detection of coronary artery disease in human. This advance has created important clinical applications to coronary artery disease diagnosis and management for areas where myocardial perfusion PET tracers are not available. We present 2 clinical cases that undergone a combined test of 1-day rest/dipyridamole-stress dynamic SPECT and ECG-gated myocardial perfusion SPECT scans using an integrated imaging protocol and demonstrate that flow parameters are capable to conclude equivocal myocardial perfusion SPECT studies, therefore increasing diagnostic benefits to add value in making clinical decisions. PMID:26053731

  11. Expression of myotubularins in blood platelets: Characterization and potential diagnostic of X-linked myotubular myopathy.

    Science.gov (United States)

    Mansour, Rana; Severin, Sonia; Xuereb, Jean-Marie; Gratacap, Marie-Pierre; Laporte, Jocelyn; Buj-Bello, Ana; Tronchère, Hélène; Payrastre, Bernard

    2016-07-29

    Phosphoinositides play a key role in the spatiotemporal control of central intracellular processes and several specific kinases and phosphatases regulating the level of these lipids are implicated in human diseases. Myotubularins are a family of 3-phosphatases acting specifically on phosphatidylinositol 3-monophosphate and phosphatidylinositol 3,5 bisphosphate. Members of this family are mutated in genetic diseases including myotubularin 1 (MTM1) and myotubularin-related protein 2 (MTMR2) which mutations are responsible of X-linked centronuclear myopathy and Charcot-Marie-Tooth neuropathy, respectively. Here we show that MTM1 is expressed in blood platelets and that hundred microliters of blood is sufficient to detect the protein by western blotting. Since the most severe cases of pathogenic mutations of MTM1 lead to loss of expression of the protein, we propose that a minimal amount of blood can allow a rapid diagnostic test of X-linked myotubular myopathy, which is currently based on histopathology of muscle biopsy and molecular genetic testing. In platelets, MTM1 is a highly active 3-phosphatase mainly associated to membranes and found on the dense granules and to a lesser extent on alpha-granules. However, deletion of MTM1 in mouse had no significant effect on platelet count and on platelet secretion and aggregation induced by thrombin or collagen stimulation. Potential compensation by other members of the myotubularin family is conceivable since MTMR2 was easily detectable by western blotting and the mRNA of several members of the family increased during in vitro differentiation of human megakaryocytes and MEG-01 cells. In conclusion, we show the presence of several myotubularins in platelets and propose that minimal amounts of blood can be used to develop a rapid diagnostic test for genetic pathologies linked to loss of expression of these phosphatases. PMID:27155155

  12. Pre-analytical factors affecting the results of laboratory blood analyses in farm animal veterinary diagnostics.

    Science.gov (United States)

    Humann-Ziehank, E; Ganter, M

    2012-07-01

    The quality of the laboratory diagnostic approach in farm animals can be severely affected by pre-analytical factors of variation. They induce increase/decrease of biochemical and hematological analyte concentrations and, as a consequence, they may cause unsuitable conclusions and decisions for animal health management and research projects. The pre-analytical period covers the preparation of sampling, the sampling procedure itself, as well as all specimen handling until the beginning of the specific laboratory analysis. Pre-analytical factors may have either an animal-related or a technique-related background. Animal-related factors cover daytime/season, meals/fasting, age, gender, altitude, drugs/anesthesia, physical exercise/stress or coinfection. Technique-related factors are the choice of the tube including serum v. plasma, effects of anticoagulants/gel separators, the anticoagulant/blood ratio, the blood collection procedure itself, specimen handling, contamination, labeling, storage and serum/plasma separation, transportation of the specimen, as well as sample preparation before analysis in the laboratory. It is essential to have proper knowledge about the importance and source of pre-analytical factors to alter the entire diagnostic process. Utmost efforts should be made to minimize controllable factors. Analytical results have to be evaluated with care considering that pre-analytical factors of variation are possible causes of misinterpretation. PMID:23031472

  13. Diagnostic Metabolomic Blood Tests for Endoluminal Gastrointestinal Cancer--A Systematic Review and Assessment of Quality.

    Science.gov (United States)

    Antonowicz, Stefan; Kumar, Sacheen; Wiggins, Tom; Markar, Sheraz R; Hanna, George B

    2016-01-01

    Advances in analytics have resulted in metabolomic blood tests being developed for the detection of cancer. This systematic review aims to assess the diagnostic accuracy of blood-based metabolomic biomarkers for endoluminal gastrointestinal (GI) cancer. Using endoscopic diagnosis as a reference standard, methodologic and reporting quality was assessed using validated tools, in addition to pathway-based informatics to biologically contextualize discriminant features. Twenty-nine studies (15 colorectal, 9 esophageal, 3 gastric, and 2 mixed) with data from 10,835 participants were included. All reported significant differences in hematologic metabolites. In pooled analysis, 246 metabolites were found to be significantly different after multiplicity correction. Incremental metabolic flux with disease progression was frequently reported. Two promising candidates have been validated in independent populations (both colorectal biomarkers), and one has been approved for clinical use. Networks analysis suggested modulation of elements of up to half of Edinburgh Human Metabolic Network subdivisions, and that the poor clinical applicability of commonly modulated metabolites could be due to extensive molecular interconnectivity. Methodologic and reporting quality was assessed as moderate-to-poor. Serum metabolomics holds promise for GI cancer diagnostics; however, future efforts must adhere to consensus standardization initiatives, utilize high-resolution discovery analytics, and compare candidate biomarkers with peer nonendoscopic alternatives. PMID:26598534

  14. Microfluidics realizes potential

    OpenAIRE

    Paula Gould

    2004-01-01

    Advanced fabrication technologies are being used to make microscale tools for fluid manipulation. Interest in the development of microfluidic devices has been encouraged by the number of fluid-based processes that could benefit from miniaturization. A number of companies are now marketing fluidic ‘lab-on-a-chip’ systems for applications in biomedical research, environmental testing, and medical diagnostics. However, the full commercial potential of this technology has yet to be realized.

  15. Microfluidic technologies for human health

    CERN Document Server

    Demirci, Utkan; Langer, Robert

    2012-01-01

    The field of microfluidics has in the last decade permeated many disciplines, from physics to biology and chemistry, and from bioengineering to medical research. One of the most important applications of lab-on-a-chip devices in medicine and related disciplines is disease diagnostics, which involves steps from biological sample/analyte loading to storage, detection, and analysis. The chapters collected in this book detail recent advances in these processes using microfluidic devices and systems. The reviews of portable devices for diagnostic purposes are likely to evoke interest and raise new

  16. Diagnostic value of combined determination of blood RF, AKA, CRP contents and ESR for rheumatoid arthritis

    International Nuclear Information System (INIS)

    Objective: To explore the clinical usefulness of combined determination of blood rheumatoid factor (RF), anti-keratin antibody (AKA), CRP contents and ESR for diagnosis of rheumatoid arthritis (RA). Methods: Serum contents of RF, CRP (with rates nephelometry) and serum contents of AKA (with indirect immuno-fluorescence method) as well as ESR were determined in 35 patients with RA, 30 patients with SLE and 30 controls. Results: The diagnostic sensitivity and specificity of RF for RA were 71.4% and 91.7% respectively, those of AKA were 34.3% and 96.7% respectively. With combined determination of RF and AKA, the sensitivity was 81.2% and the specificity was 99.7%. The acute phase reaction product CRP was very sensitive (91.4%) but non-specific (25%). The same was true for ESR (sensitivity 88.6%, specificity 83.3%). With combined determination of these four factors, the sensitivity and specificity were the highest (99.98% and 99.97% respectively). Conclusion: RF, AKA, CRP and ESR could be used as the diagnostic serum marker for rheumatoid arthritis and combined determination of these four would produce a near perfect result. (authors)

  17. Hair Sheep Blood, Citrated or Defibrinated, Fulfills All Requirements of Blood Agar for Diagnostic Microbiology Laboratory Tests

    OpenAIRE

    Yeh, Ellen; Pinsky, Benjamin A.; Banaei, Niaz; Baron, Ellen Jo

    2009-01-01

    Background Blood agar is used for the identification and antibiotic susceptibility testing of many bacterial pathogens. In the developing world, microbiologists use human blood agar because of the high cost and inhospitable conditions for raising wool sheep or horses to supply blood. Many pathogens either fail to grow entirely or exhibit morphologies and hemolytic patterns on human blood agar that confound colony recognition. Furthermore, human blood can be hazardous to handle due to HIV and ...

  18. Integrated Microfluidic Nucleic Acid Isolation, Isothermal Amplification, and Amplicon Quantification

    Directory of Open Access Journals (Sweden)

    Michael G. Mauk

    2015-10-01

    Full Text Available Microfluidic components and systems for rapid (<60 min, low-cost, convenient, field-deployable sequence-specific nucleic acid-based amplification tests (NAATs are described. A microfluidic point-of-care (POC diagnostics test to quantify HIV viral load from blood samples serves as a representative and instructive example to discuss the technical issues and capabilities of “lab on a chip” NAAT devices. A portable, miniaturized POC NAAT with performance comparable to conventional PCR (polymerase-chain reaction-based tests in clinical laboratories can be realized with a disposable, palm-sized, plastic microfluidic chip in which: (1 nucleic acids (NAs are extracted from relatively large (~mL volume sample lysates using an embedded porous silica glass fiber or cellulose binding phase (“membrane” to capture sample NAs in a flow-through, filtration mode; (2 NAs captured on the membrane are isothermally (~65 °C amplified; (3 amplicon production is monitored by real-time fluorescence detection, such as with a smartphone CCD camera serving as a low-cost detector; and (4 paraffin-encapsulated, lyophilized reagents for temperature-activated release are pre-stored in the chip. Limits of Detection (LOD better than 103 virons/sample can be achieved. A modified chip with conduits hosting a diffusion-mode amplification process provides a simple visual indicator to readily quantify sample NA template. In addition, a companion microfluidic device for extracting plasma from whole blood without a centrifuge, generating cell-free plasma for chip-based molecular diagnostics, is described. Extensions to a myriad of related applications including, for example, food testing, cancer screening, and insect genotyping are briefly surveyed.

  19. Diagnostic prediction of renal failure from blood serum analysis by FTIR spectrometry and chemometrics

    Science.gov (United States)

    Khanmohammadi, Mohammdreza; Ghasemi, Keyvan; Garmarudi, Amir Bagheri; Ramin, Mehdi

    2015-02-01

    A new diagnostic approach based on Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectrometry and classification algorithm has been introduced which provides a rapid, reliable, and easy way to perform blood test for the diagnosis of renal failure. Blood serum samples from 35 renal failure patients and 40 healthy persons were analyzed by ATR-FTIR spectrometry. The resulting data was processed by Quadratic Discriminant Analysis (QDA) and QDA combined with simple filtered method. Spectroscopic studies were performed in 900-2000 cm-1 spectral region with 3.85 cm-1 data space. Results showed 93.33% and 100% of accuracy for QDA and filter-QDA models, respectively. In the first step, 30 samples were applied to construct the model. In order to modify the capability of QDA in prediction of test samples, filter-based feature selection methods were applied. It was found that the filtered spectra coupled with QDA could correctly predict the test samples in most of the cases.

  20. : microfluidic micropipette

    OpenAIRE

    Preira, Pascal; Valignat, Marie-Pierre; Bico, José; Théodoly, Olivier

    2013-01-01

    International audience We report how cell rheology measurements can be performed by monitoring the deformation of a cell in a microfluidic constriction, provided that friction and fluid leaks effects between the cell and the walls of the microchannels are correctly taken into account. Indeed, the mismatch between the rounded shapes of cells and the angular cross-section of standard microfluidic channels hampers efficient obstruction of the channel by an incoming cell. Moreover, friction fo...

  1. Diagnostic thresholds for ambulatory blood pressure moving lower: a review based on a meta-analysis-clinical implications

    DEFF Research Database (Denmark)

    Hansen, T.W.; Kikuya, M.; Thijs, L.; Li, Y.; Boggia, J.; Bjorklund-Bodegard, K.; Torp-Pedersen, C.; Jeppesen, J.; Ibsen, H.; Staessen, J.A.

    2008-01-01

    /75 mm Hg, 130/85 mm Hg, and 110/70 mm Hg, respectively, and those for ambulatory hypertension were 130/80 mm Hg, 140/85 mm Hg, and 120/70 mm Hg. However, in clinical practice, any diagnostic threshold for blood pressure needs to be assessed in the context of the patient's overall risk profile. The IDACO...

  2. A malaria diagnostic tool based on computer vision screening and visualization of Plasmodium falciparum candidate areas in digitized blood smears.

    Directory of Open Access Journals (Sweden)

    Nina Linder

    Full Text Available INTRODUCTION: Microscopy is the gold standard for diagnosis of malaria, however, manual evaluation of blood films is highly dependent on skilled personnel in a time-consuming, error-prone and repetitive process. In this study we propose a method using computer vision detection and visualization of only the diagnostically most relevant sample regions in digitized blood smears. METHODS: Giemsa-stained thin blood films with P. falciparum ring-stage trophozoites (n = 27 and uninfected controls (n = 20 were digitally scanned with an oil immersion objective (0.1 µm/pixel to capture approximately 50,000 erythrocytes per sample. Parasite candidate regions were identified based on color and object size, followed by extraction of image features (local binary patterns, local contrast and Scale-invariant feature transform descriptors used as input to a support vector machine classifier. The classifier was trained on digital slides from ten patients and validated on six samples. RESULTS: The diagnostic accuracy was tested on 31 samples (19 infected and 12 controls. From each digitized area of a blood smear, a panel with the 128 most probable parasite candidate regions was generated. Two expert microscopists were asked to visually inspect the panel on a tablet computer and to judge whether the patient was infected with P. falciparum. The method achieved a diagnostic sensitivity and specificity of 95% and 100% as well as 90% and 100% for the two readers respectively using the diagnostic tool. Parasitemia was separately calculated by the automated system and the correlation coefficient between manual and automated parasitemia counts was 0.97. CONCLUSION: We developed a decision support system for detecting malaria parasites using a computer vision algorithm combined with visualization of sample areas with the highest probability of malaria infection. The system provides a novel method for blood smear screening with a significantly reduced need for

  3. Alterations of miR-132 are novel diagnostic biomarkers in peripheral blood of schizophrenia patients.

    Science.gov (United States)

    Yu, Hai-chuan; Wu, Jiao; Zhang, Hong-xing; Zhang, Gao-li; Sui, Juan; Tong, Wen-wen; Zhang, Xin-ya; Nie, Li-li; Duan, Ju-hong; Zhang, Li-rong; Lv, Lu-xian

    2015-12-01

    Alterations in microRNAs (miRNAs) have been considered to have diagnostic implications in most diseases, but few studies have reported dysregulated miRNAs in schizophrenia (SCZ). In order to observe an association between miRNAs and SCZ, this study was designed to investigate expression profiling of miRNAs in peripheral blood mononuclear cells (PBMCs). miRNA microarray technology was employed to compare the expression of miRNAs in PBMCs from SCZ patients (n=105) and normal controls (n=130), and real-time quantitative polymerase chain reaction (QPCR) was used to analyze the results. Several important miRNA levels were examined before and after antipsychotic treatment in first-onset SCZ patients. In addition, an SCZ-like rat model was established using dizocilpine (MK-801), and miR-132 expression in PBMCs and whole-brain tissue from SCZ-like rats was studied using QPCR. In humans, dysregulated miRNAs were observed before treatment and QPCR verified that miR-132, miR-134, miR-1271, miR-664(⁎), miR-200c and miR-432 levels were significantly decreased (Panimal assays, miR-132 levels declined in PBMCs and whole-brain tissues (both P<0.05) of the SCZ-like rats compared to controls. For the first time, our results suggest that miR-132 is a potential and superior biomarker in peripheral blood that will allow discrimination of SCZ patients from healthy controls. PMID:25985888

  4. Theoretical microfluidics

    DEFF Research Database (Denmark)

    Bruus, Henrik

    Microfluidics is a young and rapidly expanding scientific discipline, which deals with fluids and solutions in miniaturized systems, the so-called lab-on-a-chip systems. It has applications in chemical engineering, pharmaceutics, biotechnology and medicine. As the lab-on-a-chip systems grow in...... complexity, a proper theoretical understanding becomes increasingly important. The basic idea of the book is to provide a self-contained formulation of the theoretical framework of microfluidics, and at the same time give physical motivation and examples from lab-on-a-chip technology. After three chapters...... introducing microfluidics, the governing equations for mass, momentum and energy, and some basic flow solutions, the following 14 chapters treat hydraulic resistance/compliance, diffusion/dispersion, time-dependent flow, capillarity, electro- and magneto-hydrodynamics, thermal transport, two-phase flow...

  5. Microfluidics' great promise for Biology - Microfluidics as a new engine for the molecular sciences

    KAUST Repository

    Kodzius, Rimantas

    2010-06-04

    History of the Life Sciences Origins of life Discoveries and instrumentation The power of genetic variation Diagnostics based on DNA/ protein variation Genomic scanning providers DNA sequencing companies Microfluidics story Commercial products available P

  6. Deformability based sorting of red blood cells improves diagnostic sensitivity for malaria caused by Plasmodium falciparum.

    Science.gov (United States)

    Guo, Quan; Duffy, Simon P; Matthews, Kerryn; Deng, Xiaoyan; Santoso, Aline T; Islamzada, Emel; Ma, Hongshen

    2016-02-21

    The loss of red blood cell (RBC) deformability is part of the pathology of many diseases. In malaria caused by Plasmodium falciparum infection, metabolism of hemoglobin by the parasite results in progressive reduction in RBC deformability that is directly correlated with the growth and development of the parasite. The ability to sort RBCs based on deformability therefore provides a means to isolate pathological cells and to study biochemical events associated with disease progression. Existing methods have not been able to sort RBCs based on deformability or to effectively enrich for P. falciparum infected RBCs at clinically relevant concentrations. Here, we develop a method to sort RBCs based on deformability and demonstrate the ability to enrich the concentration of ring-stage P. falciparum infected RBCs (Pf-iRBCs) by >100× from clinically relevant parasitemia (asymmetrical constrictions using oscillatory flow. This mechanism provides dramatically improved selectivity over previous biophysical methods by preventing the accumulation of cells in the filter microstructure to ensure that consistent filtration forces are applied to each cell. We show that our approach dramatically improves the sensitivity of malaria diagnosis performed using both microscopy and rapid diagnostic test by converting samples with difficult-to-detect parasitemia (0.1%). PMID:26768227

  7. [Evaluation of NMR relaxation method as a diagnostic tool for donor blood analysis and patients with hematologic diseases and burns].

    Science.gov (United States)

    Gangardt, M G; Popova, O V; Shmarov, D A; Kariakina, N F; Papish, E A; Kozinets, G I

    2002-08-01

    Diagnostic value of the NMR-relaxation method in the blood plasma was estimated in the patients with different pathologies. The time of hydrogen nuclei longitudinal relaxation (T1) in the health donors of the blood, in the patients with oncopathology (hemoblastoses) and in the cases with anemia and burning disease were investigated. The time of the longitudinal relaxation (T1) was measured by automated NMR-relaxometer "Palma" (Russia). The working frequency was equal to 35 MHz, the temperature was 45 +/- 0.1 degrees C. For the single measurement 0.2 ml of blood obtained from heparinized venous blood 1.5 hours after its taking was used. The time of the longitudinal relaxation (T1) was shown to be 1.78 +/- 0.02 in the health donors, 1.70 +/- 0.06 s in cases with anemia, 1.97 +/- 0.48 c in patients with leucosis, 2.40 +/- 0.12 s in patients with burns. The sensitivity and the specificity of diagnostics of leucosis based upon the results of the only single T1 measurement in blood plasma were concluded to be 75%. It proves the significant T1 change both in patients with anemia and burning disease of the II-III degree. However it is evidently insufficient for selective use of NMR-relaxation blood plasma (serum) in the diagnostics of anemia and leucosis. The data obtained prove also the possibility of use of NMR-relaxation blood plasma (serum) for control of the hemostasis state during treatment or remission. PMID:12362635

  8. Microfluidic-chip platform for cell sorting

    Science.gov (United States)

    Malik, Sarul; Balyan, Prerna; Akhtar, J.; Agarwal, Ajay

    2016-04-01

    Cell sorting and separation are considered to be very crucial preparatory steps for numerous clinical diagnostics and therapeutics applications in cell biology research arena. Label free cell separation techniques acceptance rate has been increased to multifold by various research groups. Size based cell separation method focuses on the intrinsic properties of the cell which not only avoids clogging issues associated with mechanical and centrifugation filtration methods but also reduces the overall cost for the process. Consequentially flow based cell separation method for continuous flow has attracted the attention of millions. Due to the realization of structures close to particle size in micro dimensions, the microfluidic devices offer precise and rapid particle manipulation which ultimately leads to an extraordinary cell separation results. The proposed microfluidic device is fabricated to separate polystyrene beads of size 1 µm, 5 µm, 10 µm and 20 µm. The actual dimensions of blood corpuscles were kept in mind while deciding the particle size of polystyrene beads which are used as a model particles for study.

  9. A microfluidic device for practical label-free CD4+ T cell counting of HIV-infected subjects

    OpenAIRE

    Cheng, Xuanhong; Irimia, Daniel; Dixon, Meredith; Sekine, Kazuhiko; Demirci, Utkan; Zamir, Lee; Tompkins, Ronald G.; Rodriguez, William; Toner, Mehmet

    2006-01-01

    Practical HIV diagnostics are urgently needed in resource-limited settings. While HIV infection can be diagnosed using simple, rapid, lateral flow immunoassays, HIV disease staging and treatment monitoring require accurate counting of a particular white blood cell subset, the CD4+ T lymphocyte. To address the limitations of current expensive, technically demanding and/or time-consuming approaches, we have developed a simple CD4 counting microfluidic device. This device uses cell affinity chro...

  10. Organization of Endothelial Cells, Pericytes, and Astrocytes into a 3D Microfluidic in Vitro Model of the Blood-Brain Barrier.

    Science.gov (United States)

    Wang, Jack D; Khafagy, El-Sayed; Khanafer, Khalil; Takayama, Shuichi; ElSayed, Mohamed E H

    2016-03-01

    The endothelial cells lining the capillaries supplying the brain with oxygen and nutrients form a formidable barrier known as the blood-brain barrier (BBB), which exhibits selective permeability to small drug molecules and virtually impermeable to macromolecular therapeutics. Current in vitro BBB models fail to replicate this restrictive behavior due to poor integration of the endothelial cells with supporting cells (pericytes and astrocytes) following the correct anatomical organization observed in vivo. We report the coculture of mouse brain microvascular endothelial cells (b.End3), pericytes, with/without C8-D1A astrocytes in layered microfluidic channels forming three-dimensional (3D) bi- and triculture models of the BBB. The live/dead assay indicated high viability of all cultured cells up to 21 days. Trans-endothelial electrical resistance (TEER) values confirmed the formation of intact monolayers after 3 days in culture and showed statistically higher values for the triculture model compared to the single and biculture models. Screening the permeability of [(14)C]-mannitol and [(14)C]-urea showed the ability of bi- and triculture models to discriminate between different markers based on their size. Further, permeability of [(14)C]-mannitol across the triculture model after 18 days in culture matched its reported permeability across the BBB in vivo. Mathematical calculations also showed that the radius of the tight junctions pores (R) in the triculture model is similar to the reported diameter of the BBB in vivo. Finally, both the bi- and triculture models exhibited functional expression of the P-glycoprotein efflux pump, which increased with the increase in the number of days in culture. These results collectively indicate that the triculture model is a robust in vitro model of the BBB. PMID:26751280

  11. Evaluation of the effect of presence of blood in the stomach on endoscopic diagnostic tests for Helicobacter pylori infection

    Directory of Open Access Journals (Sweden)

    S Mittal

    2011-01-01

    Full Text Available Introduction: Presence of blood in the stomach has been thought to affect the performance of diagnostic tests used in detecting Helicobacter pylori (H. pylori in the stomach. This study evaluated the effect of blood on the efficacy of rapid urease test (RUT and microscopic appearance of the biopsy after staining with Giemsa stain. Materials and Methods: Patients with bleeding oesophageal varices who met the inclusion criteria were tested for H. pylori by RUT and microscopic examination of the biopsy. A repeat endoscopy, RUT and histology were done one month following initial presentation. The performance of the diagnostic tests was evaluated with and without the presence of intraluminal blood. A combined result of the two tests, RUT and histology, carried out in presence or absence of blood for the diagnosis of H. pylori, when considered together was considered as the gold standard. Results: Thirty six patients included in the study were in the ages ranging between 15-60 years (mean age = 44.14 years ±2.1. The combination of tests at both visits showed 20/36 (55.6% patients were positive for H. pylori. The decrease in H. pylori positivity in the presence of blood was significant for RUT (8.3% vs. 38.9%; P=0.005 and combined test (19.4% vs. 47.2%; P=0.02 but the decrease in positivity for histology (11.1% vs 30.6% was not significant (P=0.08. In the presence of blood, the sensitivity of RUT, histology and combined tests were 15%, 20% and 35%, respectively. In the absence of blood, the sensitivity of RUT, histology and combination of tests was 70%, 55% and 85%, respectively. Conclusion: Blood in the stomach significantly decreased the sensitivity of RUT, histology and the combination of both. Negative results of these tests in acute upper gastro intestinal (GI bleeding should therefore be interpreted carefully.

  12. Electroosmotic oscillatory flow of micropolar fluid in microchannels:application to dynamics of blood flow in microfluidic devices

    Institute of Scientific and Technical Information of China (English)

    JC MISRA; S CHANDRA; GC SHIT; PK KUNDU

    2014-01-01

    The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss’s law of charge distribution are solved within the framework of the Debye-H¨uckel approximation. The fluid velocity and microrotation are assumed to depend linearly on the Reynolds number. The study shows that the amplitude of microrotation is highly sensitive to the changes in the magnitude of the suction velocity and the width of the microchannel. An increase in the micropolar parameter gives rise to a decrease in the amplitude of microrotation. Numerical estimates reveal that the microrotation of the suspended microelements in blood also plays an important role in controlling the electro-osmotically actuated flow dynamics in micro-bio-fluidic devices.

  13. Microfluidic Systems for Pathogen Sensing: A Review

    Directory of Open Access Journals (Sweden)

    Peter Ertl

    2009-06-01

    Full Text Available Rapid pathogen sensing remains a pressing issue today since conventional identification methodsare tedious, cost intensive and time consuming, typically requiring from 48 to 72 h. In turn, chip based technologies, such as microarrays and microfluidic biochips, offer real alternatives capable of filling this technological gap. In particular microfluidic biochips make the development of fast, sensitive and portable diagnostic tools possible, thus promising rapid and accurate detection of a variety of pathogens. This paper will provide a broad overview of the novel achievements in the field of pathogen sensing by focusing on methods and devices that compliment microfluidics.

  14. Screening for transfusion transmissible infections using rapid diagnostic tests in Africa: a potential hazard to blood safety?

    Science.gov (United States)

    Prugger, C; Laperche, S; Murphy, E L; Bloch, E M; Kaidarova, Z; Tafflet, M; Lefrère, J-J; Jouven, X

    2016-02-01

    Rapid diagnostic tests (RDTs) are routinely used in African blood centres. We analysed data from two cross-sectional studies representing 95 blood centres in 29 African countries. Standardized panels of sera containing varying concentrations of anti-human immunodeficiency virus (HIV) antibodies (Ab), hepatitis B virus antigen (HBsAg) and antihepatitis C virus (HCV) Ab were screened using routine operational testing procedures at the centres. Sensitivity of detection using RDTs was high for HIV Ab-positive samples, but low for intermediately HBsAg (51·5%) and HCV Ab (40·6%)-positive samples. These findings suggest that current RDT use in Africa could pose a hazard to blood safety. PMID:26646317

  15. Microfluidic waves.

    Science.gov (United States)

    Utz, Marcel; Begley, Matthew R; Haj-Hariri, Hossein

    2011-11-21

    The propagation of pressure waves in fluidic channels with elastic covers is discussed in view of applications to flow control in microfluidic devices. A theory is presented which describes pressure waves in the fluid that are coupled to bending waves in the elastic cover. At low frequencies, the lateral bending of the cover dominates over longitudinal bending, leading to propagating, non-dispersive longitudinal pressure waves in the channel. The theory addresses effects due to both the finite viscosity and compressibility of the fluid. The coupled waves propagate without dispersion, as long as the wave length is larger than the channel width. It is shown that in channels of typical microfluidic dimensions, wave velocities in the range of a few 10 m s(-1) result if the channels are covered by films of a compliant material such as PDMS. The application of this principle to design microfluidic band pass filters based on standing waves is discussed. Characteristic frequencies in the range of a few kHz are readily achieved with quality factors above 30. PMID:21966667

  16. Portable, Constriction-Expansion Blood Plasma Separation and Polymerization-Based Malaria Detection.

    Science.gov (United States)

    Shatova, Tatyana A; Lathwal, Shefali; Engle, Marissa R; Sikes, Hadley D; Jensen, Klavs F

    2016-08-01

    A portable, microfluidic blood plasma separation device is presented featuring a constriction-expansion design, which produces 100.0% purity for undiluted blood at 9% yield. This level of purity represents an improvement of at least 1 order of magnitude with increased yield compared to that achieved previously using passive separation. The system features high flow rates, 5-30 μL/min plasma collection, with minimal clogging and biofouling. The simple, portable blood plasma separation design is hand-driven and can easily be incorporated with microfluidic or laboratory scale diagnostic assays. The separation system was applied to a paper-based diagnostic test for malaria that produced an amplified color change in the presence of Plasmodium falciparum histidine-rich protein 2 at a concentration well below clinical relevancy for undiluted whole blood. PMID:27366819

  17. Self-contained microfluidic systems: a review.

    Science.gov (United States)

    Boyd-Moss, Mitchell; Baratchi, Sara; Di Venere, Martina; Khoshmanesh, Khashayar

    2016-08-16

    Microfluidic systems enable rapid diagnosis, screening and monitoring of diseases and health conditions using small amounts of biological samples and reagents. Despite these remarkable features, conventional microfluidic systems rely on bulky expensive external equipment, which hinders their utility as powerful analysis tools outside of research laboratories. 'Self-contained' microfluidic systems, which contain all necessary components to facilitate a complete assay, have been developed to address this limitation. In this review, we provide an in-depth overview of self-contained microfluidic systems. We categorise these systems based on their operating mechanisms into three major groups: passive, hand-powered and active. Several examples are provided to discuss the structure, capabilities and shortcomings of each group. In particular, we discuss the self-contained microfluidic systems enabled by active mechanisms, due to their unique capability for running multi-step and highly controllable diagnostic assays. Integration of self-contained microfluidic systems with the image acquisition and processing capabilities of smartphones, especially those equipped with accessory optical components, enables highly sensitive and quantitative assays, which are discussed. Finally, the future trends and possible solutions to expand the versatility of self-contained, stand-alone microfluidic platforms are outlined. PMID:27425637

  18. Diagnostic value of blood pool imaging for limbs viability after electrical injury

    International Nuclear Information System (INIS)

    This study was undertaken to evaluate the clinical usefulness of 99mTc labelled red blood cell imaging in the detection of limbs viability after electrical injury. 8 patients were studied. There are two steps in the imaging process: artery perfusion and blood pool imaging. In the case of severe injury, in which muscles were necrotic and vessels are obstructed, no radioactivities appeared in those areas. The imaging results were proved by plastic surgery. This study shows that 99mTc-RBC blood pool imaging is a reliable method for the detection of limbs' viability after electrical injury

  19. Diagnostic of flow rate of the tumors of the boobs at increment of the blood pressure

    International Nuclear Information System (INIS)

    54 patients with ultrasonography evident tumors of the mammary glands were examined by angiography on flow rate of the blood in the tumor (14 patients with benign tumor and 40 patients with carcinoma at increment of the blood pressure. At evaluating of the findings 4 characteristic curves were obtained: first type was typical for malignant tumors; second type was characteristic for benign findings and third and fourth types were non-specific. (authors)

  20. Fully Integrated Microfluidic Device for Direct Sample-to-Answer Genetic Analysis

    Science.gov (United States)

    Liu, Robin H.; Grodzinski, Piotr

    Integration of microfluidics technology with DNA microarrays enables building complete sample-to-answer systems that are useful in many applications such as clinic diagnostics. In this chapter, a fully integrated microfluidic device [1] that consists of microfluidic mixers, valves, pumps, channels, chambers, heaters, and a DNA microarray sensor to perform DNA analysis of complex biological sample solutions is present. This device can perform on-chip sample preparation (including magnetic bead-based cell capture, cell preconcentration and purification, and cell lysis) of complex biological sample solutions (such as whole blood), polymerase chain reaction, DNA hybridization, and electrochemical detection. A few novel microfluidic techniques were developed and employed. A micromix-ing technique based on a cavitation microstreaming principle was implemented to enhance target cell capture from whole blood samples using immunomagnetic beads. This technique was also employed to accelerate DNA hybridization reaction. Thermally actuated paraffin-based microvalves were developed to regulate flows. Electrochemical pumps and thermopneumatic pumps were integrated on the chip to provide pumping of liquid solutions. The device is completely self-contained: no external pressure sources, fluid storage, mechanical pumps, or valves are necessary for fluid manipulation, thus eliminating possible sample contamination and simplifying device operation. Pathogenic bacteria detection from ~mL whole blood samples and single-nucleotide polymorphism analysis directly from diluted blood were demonstrated. The device provides a cost-effective solution to direct sample-to-answer genetic analysis, and thus has a potential impact in the fields of point-of-care genetic analysis, environmental testing, and biological warfare agent detection.

  1. Significance of procalcitonin concentration in blood plasma in septic state diagnostic

    Directory of Open Access Journals (Sweden)

    V.V. Morrison

    2010-06-01

    Full Text Available The article highlights and generalizes data presented in native and foreign scientific literature. It is devoted to the structure, synthesis and procalcitonin secretion by different cells. The main objective of the work is the significance of procalcitonin determination in septic state diagnostics

  2. Sputtered coatings for microfluidic applications

    International Nuclear Information System (INIS)

    Magnetron sputter-deposited features and coatings are finding a broad range of uses in microfluidic devices being developed at the Pacific Northwest National Laboratory. Such features are routinely incorporated into multilayer laminated microfluidic components where specific functionality is required, and where other methods for producing these features have been deemed unacceptable. Applications include electrochemical sensors, heaters and temperature probes, electrical leads and insulation layers, piezoelectric actuators and transducers, and chemical modification of surfaces. Small features, such as those required for the production of microsensor electrodes or miniature resistive heaters on microfluidic chips, were patterned using standard lithographic methods, or with masks produced by laser micromachining processes. Thin-film piezoelectric materials such as aluminum nitride have been deposited at low temperatures for use with temperature sensitive materials. Use of the coating technology and its application in the fabrication of specific microfluidic devices, including a groundwater sensor, miniature piezoelectric ultrasonic transducers and actuators, a polymerase chain reaction thermal cycler, and a microchannel flow diagnostic device, are discussed. Technical issues associated with these coatings, such as adhesion, chemical resistance, and surface defects are also addressed. (c) 2000 American Vacuum Society

  3. Microfluidic-integrated DNA nanobiosensors.

    Science.gov (United States)

    Ansari, M I Haque; Hassan, Shabir; Qurashi, Ahsanulhaq; Khanday, Firdous Ahmad

    2016-11-15

    Over the last few decades, an increased demand has emerged for integrating biosensors with microfluidic- and nanofluidic-based lab-on-chip (LOC) devices for point-of-care (POC) diagnostics, in the medical industry and environmental monitoring of pathogenic threat agents. Such a merger of microfluidics with biosensing technologies allows for the precise control of volumes, as low as one nanolitre and the integration of various types of bioassays on a single miniaturized platform. This integration offers several favorable advantages, such as low reagent consumption, automation of sample preparation, reduction in processing time, low cost analysis, minimal handling of hazardous materials, high detection accuracy, portability and disposability. This review provides a synopsis of the most recent developments in the microfluidic-integrated biosensing field by delineating the fundamental theory of microfluidics, fabrication techniques and a detailed account of the various transduction methods that are employed. Lastly, the review discusses state-of-the-art DNA biosensors with a focus on optical DNA biosensors. PMID:27179566

  4. Diagnostic Value of White Blood Cell and C-Reactive Protein in Pediatric Appendicitis

    Directory of Open Access Journals (Sweden)

    Sevgi Buyukbese Sarsu

    2016-01-01

    Full Text Available Background. Acute appendicitis (AA associated with acute phase reaction is the most prevalent disease which requires emergency surgery. Its delayed diagnosis and unnecessarily performed appendectomies lead to numerous complications. In our study, we aimed to detect the role of WBC and CRP in the exclusion of acute and complicated appendicitis and diagnostic accuracy in pediatric age group. Methods. Appendectomized patient groups were constructed based on the results of histological evaluation. The area under a receiver operating characteristic (ROC curve (AUC was performed to examine diagnostic accuracy. Results. When WBC and CRP were used in combination, based on cut-off values of ≥13.1 × 103/μL for WBC counts and ≥1.17 mg/dL for CRP level, diagnostic parameters were as follows: sensitivity, 98.7%; specificity, 71.3%; PPV, 50.6%; NPV, 99.5%; diagnostic accuracy, 77.6%; LR(+, 3.44; LR(−, 0.017. AUC values were 0.845 (95% CI 0.800–0.891 for WBC and 0.887 (95% CI 0.841–0.932 for CRP. Conclusions. For complicated appendicitis, CRP has the highest degree of diagnostic accuracy. The diagnosis of appendicitis should be made primarily based on clinical examination, and obviously more specific and systemic inflammatory markers are needed. Combined use of cut-off values of WBC (≥13100/μL and CRP (≥1.17 mg/L yields a higher sensitivity and NPV for the diagnosis of complicated appendicitis.

  5. Cell-Based Biosensors: Electrical Sensing in Microfluidic Devices

    OpenAIRE

    Noemi Rozlosnik; Katrine Kiilerich-Pedersen

    2012-01-01

    Cell-based biosensors provide new horizons for medical diagnostics by adopting complex recognition elements such as mammalian cells in microfluidic devices that are simple, cost efficient and disposable. This combination renders possible a new range of applications in the fields of diagnostics and personalized medicine. The review looks at the most recent developments in cell-based biosensing microfluidic systems with electrical and electrochemical transduction, and relevance to medical diagn...

  6. PREFACE: Nano- and microfluidics Nano- and microfluidics

    Science.gov (United States)

    Jacobs, Karin

    2011-05-01

    The field of nano- and microfluidics emerged at the end of the 1990s parallel to the demand for smaller and smaller containers and channels for chemical, biochemical and medical applications such as blood and DNS analysis [1], gene sequencing or proteomics [2, 3]. Since then, new journals and conferences have been launched and meanwhile, about two decades later, a variety of microfluidic applications are on the market. Briefly, 'the small flow becomes mainstream' [4]. Nevertheless, research in nano- and microfluidics is more than downsizing the spatial dimensions. For liquids on the nanoscale, surface and interface phenomena grow in importance and may even dominate the behavior in some systems. The studies collected in this special issue all concentrate on these type of systems and were part ot the priority programme SPP1164 'Nano- and Microfluidics' of the German Science Foundation (Deutsche Forschungsgemeinschaft, DFG). The priority programme was initiated in 2002 by Hendrik Kuhlmann and myself and was launched in 2004. Friction between a moving liquid and a solid wall may, for instance, play an important role so that the usual assumption of a no-slip boundary condition is no longer valid. Likewise, the dynamic deformations of soft objects like polymers, vesicles or capsules in flow arise from the subtle interplay between the (visco-)elasticity of the object and the viscous stresses in the surrounding fluid and, potentially, the presence of structures confining the flow like channels. Consequently, new theories were developed ( see articles in this issue by Münch and Wagner, Falk and Mecke, Bonthuis et al, Finken et al, Almenar and Rauscher, Straube) and experiments were set up to unambiguously demonstrate deviations from bulk, or 'macro', behavior (see articles in this issue by Wolff et al, Vinogradova and Belyaev, Hahn et al, Seemann et al, Grüner and Huber, Müller-Buschbaum et al, Gutsche et al, Braunmüller et al, Laube et al, Brücker, Nottebrock et al

  7. Isolation of plasma from whole blood using a microfludic chip in a continuous cross-flow

    Institute of Scientific and Technical Information of China (English)

    CHEN Xing; CUI DaFu; ZHANG LuLu

    2009-01-01

    A novel microfluidic chip is developed for crossflow filtration plasma from the whole blood which is carried out in a continuous manner. This microfluidic chip was made of a silicon substrate sealed with a compound cover. The silicon substrate fabricated by micro-electro-mechanical system (MEMS)technology consisted of microposts array, microchannels and reservoirs. Then the silicon substrate was characterized by Scaning Electron Microscopy (SEM). The performance of the microfiuidic chip was valued by the experiments of plasma isolation. During more than one hour of continuous blood infusion through the chip, there were no problems of jamming or clogging, and the plasma selectivity of 97.78% was achieved. Due to the chip's simple structure and control mechanism with a continuous,real time operating manner, this microfluidic chip is easily expected to be integrated into micro total analytical system (uTAS) which will create a microanalysis system for point-of-care diagnostics.

  8. Microfluidic electrochemical reactors

    Science.gov (United States)

    Nuzzo, Ralph G.; Mitrovski, Svetlana M.

    2011-03-22

    A microfluidic electrochemical reactor includes an electrode and one or more microfluidic channels on the electrode, where the microfluidic channels are covered with a membrane containing a gas permeable polymer. The distance between the electrode and the membrane is less than 500 micrometers. The microfluidic electrochemical reactor can provide for increased reaction rates in electrochemical reactions using a gaseous reactant, as compared to conventional electrochemical cells. Microfluidic electrochemical reactors can be incorporated into devices for applications such as fuel cells, electrochemical analysis, microfluidic actuation, pH gradient formation.

  9. Diagnostic Value of White Blood Cell and C-Reactive Protein in Pediatric Appendicitis

    OpenAIRE

    Sevgi Buyukbese Sarsu; Fatma Sarac

    2016-01-01

    Background. Acute appendicitis (AA) associated with acute phase reaction is the most prevalent disease which requires emergency surgery. Its delayed diagnosis and unnecessarily performed appendectomies lead to numerous complications. In our study, we aimed to detect the role of WBC and CRP in the exclusion of acute and complicated appendicitis and diagnostic accuracy in pediatric age group. Methods. Appendectomized patient groups were constructed based on the results of histological evaluatio...

  10. Peripheral Blood Lymphocyte Genome Damage Induced by Diagnostic Exposure to 201Ti and 99mTc: a Case Study

    International Nuclear Information System (INIS)

    The levels of genome damage induced by diagnostic exposure to radioisotopes 201Tl and 99mTc were studied in human peripheral blood leukocytes using the alkaline comet assay, the analysis of structural chromosome aberrations (CA) and cytokinesis-block micronucleus (MN) assay. A subject of study was an engineer occupationally exposed to ionising and nonionising radiation for about 25 years. Due to health problems, he has been advised to perform two nuclear medicine cardiac imaging procedures. In the first one he was given 201Tl (activity 111 MBq), while second procedure involved the exposure to 99mTc (activity 740 MBq). In the course of study (21 day) radiation doses were monitored using both active electronic, and passive film badge dosimeters. Venous blood was collected before and after administration of 201Tl, before and after administration of 99mTc, and 7 days after second cardiac imaging procedure. Although the subject received two high radiation doses in a short time period, results of the alkaline comet assay suggest that the levels of primary DNA damage in leukocytes were not significantly impaired. The highest level of CA was found in the blood sample collected after administration of 201Tl, and moderate levels after administration of 99mTc. The highest incidence of MN was observed in 3rd blood sample collected before administration of 99mTc, which was in line with the mechanisms of MN formation following exposure to ionising radiation. Low levels of primary DNA damage observed in the course of study, along with low levels of CA and MN found in 5th blood sample point to effective repair mechanisms but also suggest the existence of an adaptive response in a subject, possibly induced by his long-term occupational exposure to low doses of both ionising and nonionising radiation. (author)

  11. Microfluidics on liquid handling stations (μF-on-LHS): a new industry-compatible microfluidic platform

    Science.gov (United States)

    Kittelmann, Jörg; Radtke, Carsten P.; Waldbaur, Ansgar; Neumann, Christiane; Hubbuch, Jürgen; Rapp, Bastian E.

    2014-03-01

    Since the early days microfluidics as a scientific discipline has been an interdisciplinary research field with a wide scope of potential applications. Besides tailored assays for point-of-care (PoC) diagnostics, microfluidics has been an important tool for large-scale screening of reagents and building blocks in organic chemistry, pharmaceutics and medical engineering. Furthermore, numerous potential marketable products have been described over the years. However, especially in industrial applications, microfluidics is often considered only an alternative technology for fluid handling, a field which is industrially mostly dominated by large-scale numerically controlled fluid and liquid handling stations. Numerous noteworthy products have dominated this field in the last decade and have been inhibited the widespread application of microfluidics technology. However, automated liquid handling stations and microfluidics do not have to be considered as mutually exclusive approached. We have recently introduced a hybrid fluidic platform combining an industrially established liquid handling station and a generic microfluidic interfacing module that allows probing a microfluidic system (such as an essay or a synthesis array) using the instrumentation provided by the liquid handling station. We term this technology "Microfluidic on Liquid Handling Stations (μF-on-LHS)" - a classical "best of both worlds"- approach that allows combining the highly evolved, automated and industry-proven LHS systems with any type of microfluidic assay. In this paper we show, to the best of our knowledge, the first droplet microfluidics application on an industrial LHS using the μF-on-LHS concept.

  12. The Blood Pressure "Uncertainty Range" – a pragmatic approach to overcome current diagnostic uncertainties (II)

    OpenAIRE

    Pater Cornel

    2005-01-01

    Abstract A tremendous amount of scientific evidence regarding the physiology and physiopathology of high blood pressure combined with a sophisticated therapeutic arsenal is at the disposal of the medical community to counteract the overall public health burden of hypertension. Ample evidence has also been gathered from a multitude of large-scale randomized trials indicating the beneficial effects of current treatment strategies in terms of reduced hypertension-related morbidity and mortality....

  13. Microfluidic sieve valves

    Science.gov (United States)

    Quake, Stephen R; Marcus, Joshua S; Hansen, Carl L

    2015-01-13

    Sieve valves for use in microfluidic device are provided. The valves are useful for impeding the flow of particles, such as chromatography beads or cells, in a microfluidic channel while allowing liquid solution to pass through the valve. The valves find particular use in making microfluidic chromatography modules.

  14. Microfluidic Dye Lasers

    DEFF Research Database (Denmark)

    Kristensen, Anders; Balslev, Søren; Gersborg-Hansen, Morten;

    2006-01-01

    A technology for miniaturized, polymer based lasers, suitable for integration with planar waveguides and microfluidic networks is presented. The microfluidic dye laser device consists of a microfluidic channel with an embedded optical resonator. The devices are fabricated in a thin polymer film...

  15. Predicting Droplet Formation on Centrifugal Microfluidic Platforms

    Science.gov (United States)

    Moebius, Jacob Alfred

    Centrifugal microfluidics is a widely known research tool for biological sample and water quality analysis. Currently, the standard equipment used for such diagnostic applications include slow, bulky machines controlled by multiple operators. These machines can be condensed into a smaller, faster benchtop sample-to-answer system. Sample processing is an important step taken to extract, isolate, and convert biological factors, such as nucleic acids or proteins, from a raw sample to an analyzable solution. Volume definition is one such step. The focus of this thesis is the development of a model predicting monodispersed droplet formation and the application of droplets as a technique for volume definition. First, a background of droplet microfluidic platforms is presented, along with current biological analysis technologies and the advantages of integrating such technologies onto microfluidic platforms. Second, background and theories of centrifugal microfluidics is given, followed by theories relevant to droplet emulsions. Third, fabrication techniques for centrifugal microfluidic designs are discussed. Finally, the development of a model for predicting droplet formation on the centrifugal microfluidic platform are presented for the rest of the thesis. Predicting droplet formation analytically based on the volumetric flow rates of the continuous and dispersed phases, the ratios of these two flow rates, and the interfacial tension between the continuous and dispersed phases presented many challenges, which will be discussed in this work. Experimental validation was completed using continuous phase solutions of different interfacial tensions. To conclude, prospective applications are discussed with expected challenges.

  16. Cardiovascular magnetic resonance of myocardial edema using a short inversion time inversion recovery (STIR) black-blood technique:Diagnostic accuracy of visual and semi-quantitative assessment

    OpenAIRE

    h-Ici Darach O; Ridgway John P; Kuehne Titus; Berger Felix; Plein Sven; Sivananthan Mohan; Messroghli Daniel R

    2012-01-01

    Abstract Background The short inversion time inversion recovery (STIR) black-blood technique has been used to visualize myocardial edema, and thus to differentiate acute from chronic myocardial lesions. However, some cardiovascular magnetic resonance (CMR) groups have reported variable image quality, and hence the diagnostic value of STIR in routine clinical practice has been put into question. The aim of our study was to analyze image quality and diagnostic performance of STIR using a set of...

  17. Blood Loss From Diagnostic Laboratory Tests in Critically III Patient and Anemia

    Directory of Open Access Journals (Sweden)

    Nermin Kelebek Girgin

    2010-12-01

    Full Text Available Objective: Anemia is very common problem in critically ill patients, and it has many deleterious effects of morbidity and mortality, decreased in oxygen carrying capacity. Phlebotomy is an important factor contributing to anemia and the need for transfusion. We aimed to evaluate the volumes of blood drawn for laboratory tests from critically ill patients, and effect on anemia and transfusion practices. Materials and Methods: The study was conducted on 60 critically ill patients. Data were recorded daily including volume of the withdrawn blood, hemoglobin (Hb, indication for transfusion, and number of units transfused. Acute Physiology and Chronic Health Evaluation (APACHE II ve Sequential Organ Failure Assessment (SOFA scores, the length of stay (LOS in the intensive care unit (ICU. Results: Thirty six of the patients (60% that transfused had significantly higher admitting APACHE II and SOFA scores (p<0.01, p<0.001. The average total volume drawn per patient was 13.05 mL for the 24-hour period except the first day in admission the ICU. The mean volume drawn the first day was detected as 27.90 mL. Total volumes drawn were significantly higher in patients that transfused at the end of second and third week (p<0.001, p<0.001. The mean pretransfusion Hb level was 8.17 g/dL, and 44.5% of all transfusions were performed within the first week. The mean ICU LOS was longer in transfused patients (p<0.001 and mortality in the transfused patients also was significantly higher (p<0.05. Conclusion: Blood drawn and transfusion need increased with prolonged ICU stay. Additionally, patients’ health condition affects the requirement of transfusion. (Journal of the Turkish Society of Intensive Care 2010; 8: 61-5

  18. Biomolecular urease thin films grown by laser techniques for blood diagnostic applications

    International Nuclear Information System (INIS)

    Matrix assisted pulsed laser evaporation (MAPLE) was used for growing urease thin films designed for bio-sensor applications in clinical diagnostics. The targets exposed to laser radiation were made from a frozen composite manufactured by dissolving biomaterials in distilled water. We used a UV KrF* (λ = 248 nm, τFWHM ≅ 30 ns, ν = 10 Hz) excimer source for multipulse laser irradiation of the frozen targets cooled with Peltier elements. The laser source was operated at an incident fluence of 0.4 J/cm2. Urease activity and kinetics were assayed by the Worthington method that monitors urea hydrolysis by coupling ammonia production to a glutamate dehydrogenase reaction. A decrease in absorbance was measured at 340 nm and correlated with the enzymatic activity of urease. We show that the urease films obtained by MAPLE techniques remain active up to three months after deposition.

  19. Transforming the blood glucose meter into a general healthcare meter for in vitro diagnostics in mobile health.

    Science.gov (United States)

    Lan, Tian; Zhang, Jingjing; Lu, Yi

    2016-01-01

    Recent advances in mobile network and smartphones have provided an enormous opportunity for transforming in vitro diagnostics (IVD) from central labs to home or other points of care (POC). A major challenge to achieving the goal is a long time and high costs associated with developing POC IVD devices in mobile Health (mHealth). Instead of developing a new POC device for every new IVD target, we and others are taking advantage of decades of research, development, engineering and continuous improvement of the blood glucose meter (BGM), including those already integrated with smartphones, and transforming the BGM into a general healthcare meter for POC IVDs of a wide range of biomarkers, therapeutic drugs and other analytical targets. In this review, we summarize methods to transduce and amplify selective binding of targets by antibodies, DNA/RNA aptamers, DNAzyme/ribozymes and protein enzymes into signals such as glucose or NADH that can be measured by commercially available BGM, making it possible to adapt many clinical assays performed in central labs, such as immunoassays, aptamer/DNAzyme assays, molecular diagnostic assays, and enzymatic activity assays onto BGM platform for quantification of non-glucose targets for a wide variety of IVDs in mHealth. PMID:26946282

  20. Low molecular weight blood plasma proteome – a source of differential diagnostic biomarkers of ovarian cancer

    Directory of Open Access Journals (Sweden)

    V. Ye. Shevchenko

    2014-11-01

    Full Text Available At present, there is no screening test for the early detecting of ovarian cancer, one of the most lethal form of gynaecological malignancy in the worldwide. In this study the new methodology for the search of tumor markers of ovarian cancer, involving profiling the low-molecular blood plasma proteomes, is developed, unified and approved. The given approach included three basic components: pre-preparation of samples, matrix-assisted laser desorption / ionization time-of-flight mass spectrometry and bioinformatics software for mass spectral data processing. Opportunities and prospects of the developed approach for the detection of potential ovarian cancer markers were shown. For search of potential tumor markers, screening of 56 blood plasma samples from ovarian cancer patients and 36 benign ovarian neoplasia samples were carried out.As a result of the present research, peptides / polypeptides which can be used in future for detecting this pathology were found out.

  1. The diagnostic utility of stabilized blood for detection of foot-and-mouth disease virus RNA by RT-qPCR

    DEFF Research Database (Denmark)

    S. Fontél, Kristina; Bøtner, Anette; Belsham, Graham;

    In Europe, clinical signs indicative of foot-and-mouth disease (FMD), would immediately lead to collection of blood and relevant organ material for further laboratory examination for this vesicular disease virus. Today, the first line system for detection of virus in the sample material is real t...... time RT-PCR (RT-qPCR). The aim of this study was to investigate the diagnostic utility of stabilized blood for detection of FMDV RNA in this system....

  2. The diagnostic utility of stabilized blood for detection of foot-and-mouth disease virus RNA by RT-qPCR

    OpenAIRE

    S. Fontél, Kristina; Bøtner, Anette; Belsham, Graham; Lohse, Louise

    2014-01-01

    In Europe, clinical signs indicative of foot-and-mouth disease (FMD), would immediately lead to collection of blood and relevant organ material for further laboratory examination for this vesicular disease virus. Today, the first line system for detection of virus in the sample material is real time RT-PCR (RT-qPCR). The aim of this study was to investigate the diagnostic utility of stabilized blood for detection of FMDV RNA in this system.

  3. LINE1 methylation levels associated with increased bladder cancer risk in pre-diagnostic blood DNA among US (PLCO) and European (ATBC) cohort study participants

    OpenAIRE

    Andreotti, Gabriella; Karami, Sara; Ruth M Pfeiffer; Hurwitz, Lauren; Liao, Linda M; Weinstein, Stephanie J.; Albanes, Demetrius; Virtamo, Jarmo; Silverman, Debra T.; Rothman, Nathaniel; Moore, Lee E.

    2013-01-01

    Global methylation in blood DNA has been associated with bladder cancer risk in case-control studies, but has not been examined prospectively. We examined the association between LINE1 total percent 5-methylcytosine and bladder cancer risk using pre-diagnostic blood DNA from the United States-based, Prostate, Lung, Colorectal, Ovarian Cancer Screening Trial (PLCO) (299 cases/676 controls), and the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) cohort of Finnish male smokers (391 cas...

  4. Dynamic alteration of telomerase expression and its diagnostic significance in liver or peripheral blood for hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Deng-Fu Yao; Wei Wu; Min Yao; Li-Wei Qiu; Xin-Hua Wu; Xiao-Qin Su; Li Zou; Deng-Bing Yao; Xian-Yong Meng

    2006-01-01

    AIM: To investigate the dynamic alteration of telomerase expression during development of hepatocellular carcinoma (HCC) and its diagnostic implications in liver tissues or peripheral blood mononuclear cells for HCC.METHODS: Dynamic expressions of liver telomerase during malignant transformation of hepatocytes were observed in Sprague-Dawly (SD) rats fed with 0.05% of 2-fluoenyacetamide (2-FAA). Total RNA and telomerase were extracted from rat or human liver tissues. The telomerase activities in livers and in circulating blood were detected by a telomeric repeat amplification protocol-enzyme-linked immunosorbent assay (TRAPELISA), and its diagnostic value was investigated in patients with benign or malignant liver diseases.RESULTS: The hepatoma model displayed the dynamic expression of hepatic telomerase during HCC development. The telomerase activities were consistent with liver total RNA levels (r = 0.83, P<0.01) at the stages of degeneration, precancerosis, and cancerization of hepatocytes. In HCC patients, the telomerase levels in HCC tissues were significantly higher than in their adjacent non-cancerous tissues, but liver total RNA levels were lower in the former than in the latter. Although the circulating telomerase of HCC patients was abnormally expressed among patients with chronic liver diseases,the telomerase activity was a non-specific marker for HCC diagnosis, because the incidence was 15.7% in normal control, 25% in chronic hepatitis, 45.9% in liver cirrhosis, and 85.2% in HCC, respectively when absorbance value of telomerase activity was more than 0.2. If the value was over 0.6, the incidence was 60%in HCC group and 0% in any of the others (P<0.01)except in two cases with liver cirrhosis. However, the combination of circulating telomerase with serum alphafetoprotein level could increase the positive rate and the accuracy (92.6%, 125 of 135) of HCC diagnosis.CONCLUSION: The overexpression of telomerase is associated with HCC development, and its

  5. Impact of uncontrolled blood pressure on diagnostic accuracy of coronary flow reserve for detecting significant coronary stenosis in hypertensive patients

    Institute of Scientific and Technical Information of China (English)

    LI Wei-hong; XU Wei-xian; LI Zhao-ping; LI Cui-ping; WANG Xin-yu; HE Li-yun; ZHAO Wei

    2013-01-01

    Baciground Impaired coronary flow reserve (CFR) in patients with hypertension may be caused by epicardial coronary stenosis or microvascular dysfunction.Antihypertensive treatment has been shown to improve coronary microvascular dysfunction.The aim of this study was to evaluate the impact of uncontrolled blood pressure (BP) on diagnostic accuracy of CFR for detecting significant coronary stenosis.Methods A total of 98 hypertensive patients scheduled for coronary angiography (CAG) due to chest pain were studied.Of them,45 patients had uncontrolled BP (defined as the office BP >140/90 mmHg (1 mmHg=0.133 kPa) in general hypertensive patients,or >130/80 mmHg in hypertensive individuals with diabetes mellitus),and the remaining 53 patients had well-controlled BP.CFR was measured in the left anterior descending coronary artery (LAD) during adenosine triphosphate-induced hyperemia by non-invasive transthoracic Doppler echocardiography (TTDE) within 48 hours prior to CAG.Significant LAD stenosis was defined as >70% luminal narrowing.Diagnostic accuracy of CFR for detecting significant coronary stenosis was analyzed with a receiver operating characteristic analysis.Results CFR was significantly lower in patients with uncontrolled BP than in those with well-controlled BP (2.1±0.6 vs.2.6±0.9,P <0.01).Multivariate linear regression analysis of the study showed that the value of CFR was independently associated with the angiographically determined degree of LAD stenosis (β=-0.445,P <0.0001) and the presence of uncontrolled BP (β=-0.272,P=0.014).With a receiver operating characteristic analysis,CFR <2.2 was the optimal cut-off value for detecting LAD stenosis in all hypertensive patients (AUC 0.83,95%C/0.75-0.91) with a sensitivity of 75%,a specificity of 78%,and an accuracy of 77%.A significant reduction of diagnostic specificity was observed in patients with uncontrolled BP compared with those with well-controlled BP (67% vs.93%,P=0

  6. Recent Advances in Applications of Droplet Microfluidics

    Directory of Open Access Journals (Sweden)

    Wei-Lung Chou

    2015-09-01

    Full Text Available Droplet-based microfluidics is a colloidal and interfacial system that has rapidly progressed in the past decade because of the advantages of low fabrication costs, small sample volumes, reduced analysis durations, high-throughput analysis with exceptional sensitivity, enhanced operational flexibility, and facile automation. This technology has emerged as a new tool for many recently used applications in molecular detection, imaging, drug delivery, diagnostics, cell biology and other fields. Herein, we review recent applications of droplet microfluidics proposed since 2013.

  7. MR-based cerebral blood volume maps as a diagnostic tool for brain tumours

    International Nuclear Information System (INIS)

    Today contrast enhanced MR imaging is a reliable method for detecting mostly distinguishing between different histological types of tumours. In this study we use a MR-based method to measure the regional cerebral blood volume (rCBV). Using this technique we try to judge the grading and vitality of the tumours. 26 patients with various types of brain tumours were examined. To calculate rCBV-maps of one slice, low-dosed Gd-DTPA was injected as a bolus. Using the relaxation effect the obtained signal intensity-time curves were converted pixel-wise into rCBV images. For the tumours rCBV-ratios were calculated relative to the corresponding area in the contralateral hemisphere. In the investigated group all tumours were detected on the basis of a raised rCBV-ratio. Since only vital parts of the tumour are perfused, the rCBV maps may be used to determine the place of biopsy. (orig./MG)

  8. Infrared tomography for diagnostic imaging of port wine stain blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, D. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    The objective of this work is the development of Infrared Tomography (IRT) for detecting and characterizing subsurface chromophores in human skin. Characterization of cutaneous chromophores is crucial for advances in the laser treatment of pigmented lesions (e.g., port wine stain birthmarks and tatoos). Infrared tomography (IRT) uses a fast infrared focal plane array (IR-FPA) to detect temperature rises in a substrate induced by pulsed radiation. A pulsed laser is used to produce transient heating of an object. The temperature rise, due to the optical absorption of the pulsed laser light, creates an increase in infrared emission which is measured by the IR-FPA. Although the application of IRT to image subsurface cracks due to metal fatigue is a topic of great interest in the aircraft industry, the application to image subsurface chromophores in biological materials is novel. We present an image recovery method based on a constrained conjugate gradient algorithm that has obtained the first ever high quality images of port wine blood vessels.

  9. Regional cerebral blood flow in normal pressure hydrocephalus: diagnostic and prognostic aspects

    International Nuclear Information System (INIS)

    Relative regional cerebral blood flow (rrCBF) was measured by SPET using 99mTc-HMPAO as flow tracer, in 23 patients with normal pressure hydrocephalus (NPH). 1000 MBq 99mTc-HMPAO was given intravenously and the rrCBF calculated as regional/cerebellar count level ratios. The patients were examined before and 3-12 months after ventriculoperitoneal shunt surgery. rrCBF was also determined in ten healthy aged matched volunteers who served as controls. The NPH patients had decreased rrCBF in the hippocampal regions and in the frontal and parietal white matter as compared to the controls. The frontal/parietal rrCBF ratio correlated with both psychiatric disability and the preoperative degree of incontinence. Decreased flow in frontal white matter, frontoparietal and hippocampal grey matter and a low frontalparietal grey matter flow ratio preoperatively correlated with improvement in both Mini Mental State score and psychiatric disability after shunt surgery. After shunt surgery the rrCBF increased in the mesencephalon, frontal grey and white matter, parietal white matter and hippocampus. The flow increase in hippocampal regions and frontal white matter correlated with improvement in psychiatric symptomatology. The results of this study regarding the frontal and hippocampal rrCBF patterns, and the clinical correlation, support the hypothesis that CBF changes in these regions are of patohphysiological and prognostic importance in NPH. (orig./MG)

  10. Diagnostic tool for red blood cell membrane disorders: Assessment of a new generation ektacytometer.

    Science.gov (United States)

    Da Costa, Lydie; Suner, Ludovic; Galimand, Julie; Bonnel, Amandine; Pascreau, Tiffany; Couque, Nathalie; Fenneteau, Odile; Mohandas, Narla

    2016-01-01

    Inherited red blood cell (RBC) membrane disorders, such as hereditary spherocytosis, elliptocytosis and hereditary ovalocytosis, result from mutations in genes encoding various RBC membrane and skeletal proteins. The RBC membrane, a composite structure composed of a lipid bilayer linked to a spectrin/actin-based membrane skeleton, confers upon the RBC unique features of deformability and mechanical stability. The disease severity is primarily dependent on the extent of membrane surface area loss. RBC membrane disorders can be readily diagnosed by various laboratory approaches that include RBC cytology, flow cytometry, ektacytometry, electrophoresis of RBC membrane proteins and genetics. The reference technique for diagnosis of RBC membrane disorders is the osmotic gradient ektacytometry. However, in spite of its recognition as the reference technique, this technique is rarely used as a routine diagnosis tool for RBC membrane disorders due to its limited availability. This may soon change as a new generation of ektacytometer has been recently engineered. In this review, we describe the workflow of the samples shipped to our Hematology laboratory for RBC membrane disorder analysis and the data obtained for a large cohort of French patients presenting with RBC membrane disorders using a newly available version of the ektacytomer. PMID:26603718

  11. Visualization and measurement of capillary-driven blood flow using spectral domain optical coherence tomography

    OpenAIRE

    Cito, Salvatore; Ahn, Yeh-Chan; Pallares, Jordi; Duarte, Rodrigo Martinez; Chen, Zhongping; Madou, Marc; Katakis, Ioanis

    2012-01-01

    Capillary-driven flow (CD-flow) in microchannels plays an important role in many microfluidic devices. These devices, the most popular being those based in lateral flow, are becoming increasingly used in health care and diagnostic applications. CD-flow can passively pump biological fluids as blood, serum or plasma, in microchannels and it can enhance the wall mass transfer by exploiting the convective effects of the flow behind the meniscus. The flow behind the meniscus has not been experimen...

  12. Design and Testing of Digital Microfluidic Biochips

    CERN Document Server

    Zhao, Yang

    2013-01-01

    This book provides a comprehensive methodology for automated design, test and diagnosis, and use of robust, low-cost, and manufacturable digital microfluidic systems. It focuses on the development of a comprehensive CAD optimization framework for digital microfluidic biochips that unifies different design problems. With the increase in system complexity and integration levels, biochip designers can utilize the design methods described in this book to evaluate different design alternatives, and carry out design-space exploration to obtain the best design point. Describes practical design automation tools that address different design problems (e.g., synthesis, droplet routing, control-pin mapping, testing and diagnosis, and error recovery) in a unified manner; Applies test pattern generation and error-recovery techniques for digital microfluidics-based biochips; Uses real bioassays as evaluation examples, e.g., multiplexed in vitro human physiological fluids diagnostics, PCR, protein crystallization.  

  13. Designing Polymeric Microfluidic Platforms for Biomedical Applications

    DEFF Research Database (Denmark)

    Vedarethinam, Indumathi

    Micro- and Nanotechnology have the potential to offer a smart solution for diagnostics and academia research with rapid, low cost, robust analysis systems to facilitate biological analyses. New, high throughput microfluidic platforms have the potential to surpass in performance the conventional...... analyses systems in use today. The overall goal of this PhD project is to address two different areas using microfluidics : i) Chromosome analysis by metaphase FISH such a platform, if successful, can immediately substitute the routine, labor-intensive, glass slide-based FISH analyses in Clinical...... Cytogenetics laboratories. During the course of this project, initially the suitability of the polymeric chip substrate was tested and a microfluidic device was developed for performing interphase FISH analysis. With this device, the key factors involved in chromosome spreading crucial to FISH analysis were...

  14. Microfluidic Dye Lasers

    DEFF Research Database (Denmark)

    Kristensen, Anders; Balslev, Søren; Gersborg-Hansen, Morten; Olsen, Brian Bilenberg; Rasmussen, Torben Bygvraa; Hansen, Michael Rosenlund Søndertoft; Nilsson, Daniel; Mortensen, N. Asger

    A technology for miniaturized, polymer based lasers, suitable for integration with planar waveguides and microfluidic networks is presented. The microfluidic dye laser device consists of a microfluidic channel with an embedded optical resonator. The devices are fabricated in a thin polymer film...... sandwiched between two glass substrates. The devices are defined in the 1-10 mum thick polymer film by photolithography, nanoimprinting or by electron beam lithography, and the lid is bonded using adhesive polymer bonding....

  15. Miniaturization and microfluidics

    OpenAIRE

    Foret, F; Smejkal, P.; Macka, M.

    2013-01-01

    While miniaturization is a prerequisite of achieving portability in LC systems, microfluidics represents a qualitative step toward chip-based LC systems. This short chapter provides an excursion into the microfluidics for separations with a brief overview of some of the commercial systems. It is worth stressing that, while the development and introduction of new microfluidic instrumentation is just at its beginning, the miniaturized technology is being used quite often in commercial sys...

  16. Microfluidics in biotechnology

    OpenAIRE

    Ivanov Dimitri; Barry Richard

    2004-01-01

    Abstract Microfluidics enables biotechnological processes to proceed on a scale (microns) at which physical processes such as osmotic movement, electrophoretic-motility and surface interactions become enhanced. At the microscale sample volumes and assay times are reduced, and procedural costs are lowered. The versatility of microfluidic devices allows interfacing with current methods and technologies. Microfluidics has been applied to DNA analysis methods and shown to accelerate DNA microarra...

  17. Bio-functionalized silk hydrogel microfluidic systems.

    Science.gov (United States)

    Zhao, Siwei; Chen, Ying; Partlow, Benjamin P; Golding, Anne S; Tseng, Peter; Coburn, Jeannine; Applegate, Matthew B; Moreau, Jodie E; Omenetto, Fiorenzo G; Kaplan, David L

    2016-07-01

    Bio-functionalized microfluidic systems were developed based on a silk protein hydrogel elastomeric materials. A facile multilayer fabrication method using gelatin sacrificial molding and layer-by-layer assembly was implemented to construct interconnected, three dimensional (3D) microchannel networks in silk hydrogels at 100 μm minimum feature resolution. Mechanically activated valves were implemented to demonstrate pneumatic control of microflow. The silk hydrogel microfluidics exhibit controllable mechanical properties, long-term stability in various environmental conditions, tunable in vitro and in vivo degradability in addition to optical transparency, providing unique features for cell/tissue-related applications than conventional polydimethylsiloxane (PDMS) and existing hydrogel-based microfluidic options. As demonstrated in the work here, the all aqueous-based fabrication process at ambient conditions enabled the incorporation of active biological substances in the bulk phase of these new silk microfluidic systems during device fabrication, including enzymes and living cells, which are able to interact with the fluid flow in the microchannels. These silk hydrogel-based microfluidic systems offer new opportunities in engineering active diagnostic devices, tissues and organs that could be integrated in vivo, and for on-chip cell sensing systems. PMID:27077566

  18. Material Biocompatibility for PCR Microfluidic Chips

    KAUST Repository

    Kodzius, Rimantas

    2010-04-23

    As part of the current miniaturization trend, biological reactions and processes are being adapted to microfluidics devices. PCR is the primary method employed in DNA amplification, its miniaturization is central to efforts to develop portable devices for diagnostics and testing purposes. A problem is the PCR-inhibitory effect due to interaction between PCR reagents and the surrounding environment, which effect is increased in high-surface-are-to-volume ration microfluidics. In this study, we evaluated the biocompatibility of various common materials employed in the fabrication of microfluidic chips, including silicon, several kinds of silicon oxide, glasses, plastics, wax, and adhesives. Two-temperature PCR was performed with these materials to determine their PCR-inhibitory effect. In most of the cases, addition of bovine serum albumin effectively improved the reaction yield. We also studied the individual PCR components from the standpoint of adsorption. Most of the materials did not inhibit the DNA, whereas they did show noticeable interaction with the DNA polymerase. Our test, instead of using microfluidic devices, can be easily conducted in common PCR tubes using a standard bench thermocycler. Our data supports an overview of the means by which the materials most bio-friendly to microfluidics can be selected.

  19. Latex Micro-balloon Pumping in Centrifugal Microfluidic Platforms

    OpenAIRE

    Aeinehvand, Mohammad Mahdi; Ibrahim, Fatimah; Al-Faqheri, Wisam; Thio, Tzer Hwai Gilbert; Kazemzadeh, Amin; Wadi harun, Sulaiman; Madou, Marc

    2014-01-01

    Centrifugal microfluidic platforms have emerged as point-of-care diagnostic tools. However, the unidirectional nature of the centrifugal force limits the available space for multi-stepped processes on a single microfluidics disc. To overcome this limitation, a passive pneumatic pumping method actuated at high rotational speeds has been previously proposed to pump liquid against the centrifugal force. In this paper, a novel micro-balloon pumping method that relies on elastic energy stored in a...

  20. Rapid and label-free microfluidic neutrophil purification and phenotyping in diabetes mellitus.

    Science.gov (United States)

    Hou, Han Wei; Petchakup, Chayakorn; Tay, Hui Min; Tam, Zhi Yang; Dalan, Rinkoo; Chew, Daniel Ek Kwang; Li, King Ho Holden; Boehm, Bernhard O

    2016-01-01

    Advanced management of dysmetabolic syndromes such as diabetes will benefit from a timely mechanistic insight enabling personalized medicine approaches. Herein, we present a rapid microfluidic neutrophil sorting and functional phenotyping strategy for type 2 diabetes mellitus (T2DM) patients using small blood volumes (fingerprick ~100 μL). The developed inertial microfluidics technology enables single-step neutrophil isolation (>90% purity) without immuno-labeling and sorted neutrophils are used to characterize their rolling behavior on E-selectin, a critical step in leukocyte recruitment during inflammation. The integrated microfluidics testing methodology facilitates high throughput single-cell quantification of neutrophil rolling to detect subtle differences in speed distribution. Higher rolling speed was observed in T2DM patients (P < 0.01) which strongly correlated with neutrophil activation, rolling ligand P-selectin glycoprotein ligand 1 (PSGL-1) expression, as well as established cardiovascular risk factors (cholesterol, high-sensitive C-reactive protein (CRP) and HbA1c). Rolling phenotype can be modulated by common disease risk modifiers (metformin and pravastatin). Receiver operating characteristics (ROC) and principal component analysis (PCA) revealed neutrophil rolling as an important functional phenotype in T2DM diagnostics. These results suggest a new point-of-care testing methodology, and neutrophil rolling speed as a functional biomarker for rapid profiling of dysmetabolic subjects in clinical and patient-oriented settings. PMID:27381673

  1. Rapid and label-free microfluidic neutrophil purification and phenotyping in diabetes mellitus

    Science.gov (United States)

    Hou, Han Wei; Petchakup, Chayakorn; Tay, Hui Min; Tam, Zhi Yang; Dalan, Rinkoo; Chew, Daniel Ek Kwang; Li, King Ho Holden; Boehm, Bernhard O.

    2016-07-01

    Advanced management of dysmetabolic syndromes such as diabetes will benefit from a timely mechanistic insight enabling personalized medicine approaches. Herein, we present a rapid microfluidic neutrophil sorting and functional phenotyping strategy for type 2 diabetes mellitus (T2DM) patients using small blood volumes (fingerprick ~100 μL). The developed inertial microfluidics technology enables single-step neutrophil isolation (>90% purity) without immuno-labeling and sorted neutrophils are used to characterize their rolling behavior on E-selectin, a critical step in leukocyte recruitment during inflammation. The integrated microfluidics testing methodology facilitates high throughput single-cell quantification of neutrophil rolling to detect subtle differences in speed distribution. Higher rolling speed was observed in T2DM patients (P < 0.01) which strongly correlated with neutrophil activation, rolling ligand P-selectin glycoprotein ligand 1 (PSGL-1) expression, as well as established cardiovascular risk factors (cholesterol, high-sensitive C-reactive protein (CRP) and HbA1c). Rolling phenotype can be modulated by common disease risk modifiers (metformin and pravastatin). Receiver operating characteristics (ROC) and principal component analysis (PCA) revealed neutrophil rolling as an important functional phenotype in T2DM diagnostics. These results suggest a new point-of-care testing methodology, and neutrophil rolling speed as a functional biomarker for rapid profiling of dysmetabolic subjects in clinical and patient-oriented settings.

  2. Rapid and label-free microfluidic neutrophil purification and phenotyping in diabetes mellitus

    Science.gov (United States)

    Hou, Han Wei; Petchakup, Chayakorn; Tay, Hui Min; Tam, Zhi Yang; Dalan, Rinkoo; Chew, Daniel Ek Kwang; Li, King Ho Holden; Boehm, Bernhard O.

    2016-07-01

    Advanced management of dysmetabolic syndromes such as diabetes will benefit from a timely mechanistic insight enabling personalized medicine approaches. Herein, we present a rapid microfluidic neutrophil sorting and functional phenotyping strategy for type 2 diabetes mellitus (T2DM) patients using small blood volumes (fingerprick ~100 μL). The developed inertial microfluidics technology enables single-step neutrophil isolation (>90% purity) without immuno-labeling and sorted neutrophils are used to characterize their rolling behavior on E-selectin, a critical step in leukocyte recruitment during inflammation. The integrated microfluidics testing methodology facilitates high throughput single-cell quantification of neutrophil rolling to detect subtle differences in speed distribution. Higher rolling speed was observed in T2DM patients (P reactive protein (CRP) and HbA1c). Rolling phenotype can be modulated by common disease risk modifiers (metformin and pravastatin). Receiver operating characteristics (ROC) and principal component analysis (PCA) revealed neutrophil rolling as an important functional phenotype in T2DM diagnostics. These results suggest a new point-of-care testing methodology, and neutrophil rolling speed as a functional biomarker for rapid profiling of dysmetabolic subjects in clinical and patient-oriented settings.

  3. Rapid and label-free microfluidic neutrophil purification and phenotyping in diabetes mellitus

    Science.gov (United States)

    Hou, Han Wei; Petchakup, Chayakorn; Tay, Hui Min; Tam, Zhi Yang; Dalan, Rinkoo; Chew, Daniel Ek Kwang; Li, King Ho Holden; Boehm, Bernhard O.

    2016-01-01

    Advanced management of dysmetabolic syndromes such as diabetes will benefit from a timely mechanistic insight enabling personalized medicine approaches. Herein, we present a rapid microfluidic neutrophil sorting and functional phenotyping strategy for type 2 diabetes mellitus (T2DM) patients using small blood volumes (fingerprick ~100 μL). The developed inertial microfluidics technology enables single-step neutrophil isolation (>90% purity) without immuno-labeling and sorted neutrophils are used to characterize their rolling behavior on E-selectin, a critical step in leukocyte recruitment during inflammation. The integrated microfluidics testing methodology facilitates high throughput single-cell quantification of neutrophil rolling to detect subtle differences in speed distribution. Higher rolling speed was observed in T2DM patients (P < 0.01) which strongly correlated with neutrophil activation, rolling ligand P-selectin glycoprotein ligand 1 (PSGL-1) expression, as well as established cardiovascular risk factors (cholesterol, high-sensitive C-reactive protein (CRP) and HbA1c). Rolling phenotype can be modulated by common disease risk modifiers (metformin and pravastatin). Receiver operating characteristics (ROC) and principal component analysis (PCA) revealed neutrophil rolling as an important functional phenotype in T2DM diagnostics. These results suggest a new point-of-care testing methodology, and neutrophil rolling speed as a functional biomarker for rapid profiling of dysmetabolic subjects in clinical and patient-oriented settings. PMID:27381673

  4. Tunable Microfluidic Dye Laser

    DEFF Research Database (Denmark)

    Olsen, Brian Bilenberg; Helbo, Bjarne; Kutter, Jörg Peter;

    2003-01-01

    We present a tunable microfluidic dye laser fabricated in SU-8. The tunability is enabled by integrating a microfluidic diffusion mixer with an existing microfluidic dye laser design by Helbo et al. By controlling the relative flows in the mixer between a dye solution and a solvent......, the concentration of dye in the laser cavity can be adjusted, allowing the wavelength to be tuned. Wavelength tuning controlled by the dye concentration was demonstrated with macroscopic dye lasers already in 1971, but this principle only becomes practically applicable by the use of microfluidic mixing...

  5. Portable microfluidic and smartphone-based devices for monitoring of cardiovascular diseases at the point of care.

    Science.gov (United States)

    Hu, Jie; Cui, Xingye; Gong, Yan; Xu, Xiayu; Gao, Bin; Wen, Ting; Lu, Tian Jian; Xu, Feng

    2016-01-01

    Cardiovascular diseases (CVDs) are the main causes of morbidity and mortality in the world where about 4 in every 5 CVD deaths happen in low- and middle-income countries (LMICs). Most CVDs are preventable and curable, which is largely dependent on timely and effective interventions, including diagnosis, prognosis and therapeutic monitoring. However, these interventions are high-cost in high income countries and are usually lacking in LMICs. Thanks to the rapid development of microfluidics and nanotechnology, lots of portable analytical devices are developed for detection of CVDs at the point-of-care (POC). In the meantime, smartphone, as a versatile and powerful handheld tool, has been employed not only as a reader for microfluidic assays, but also as an analyzer for physiological indexes. In this review, we present a comprehensive introduction of the current status and potential development direction on POC diagnostics for CVDs. First of all, we introduce some main facts about CVDs and their standard diagnostic procedures and methods. Second, we discuss about both commercially available POC devices and developed prototypes for detection of CVDs via immunoassays. Subsequently, we report the advances in smartphone-based readout for microfluidic assays. Finally, we present some examples using smartphone, individually or combined with other components or devices, for CVD monitoring. We envision an integrated smartphone-based system capable of functioning blood tests, disease examination, and imaging will come in the future. PMID:26898179

  6. High-throughput miniaturized microfluidic microscopy with radially parallelized channel geometry.

    Science.gov (United States)

    Jagannadh, Veerendra Kalyan; Bhat, Bindu Prabhath; Nirupa Julius, Lourdes Albina; Gorthi, Sai Siva

    2016-03-01

    In this article, we present a novel approach to throughput enhancement in miniaturized microfluidic microscopy systems. Using the presented approach, we demonstrate an inexpensive yet high-throughput analytical instrument. Using the high-throughput analytical instrument, we have been able to achieve about 125,880 cells per minute (more than one hundred and twenty five thousand cells per minute), even while employing cost-effective low frame rate cameras (120 fps). The throughput achieved here is a notable progression in the field of diagnostics as it enables rapid quantitative testing and analysis. We demonstrate the applicability of the instrument to point-of-care diagnostics, by performing blood cell counting. We report a comparative analysis between the counts (in cells per μl) obtained from our instrument, with that of a commercially available hematology analyzer. PMID:26781098

  7. Diagnostic informative value of gastroduodenal regulatory peptides of the blood serum on an empty stomach and after test breakfasts of various compositions

    International Nuclear Information System (INIS)

    Gastrin, secretin and cholecystokinin were determined by a radioimmunoassay in healthy persons (19) and in patients with peptic ulcer (13) on an empty stomach and after test breakfasts with different nutrients. In the healthy persons the blood concentration of regulatory peptides was lower than in the patients. Breakfasts increased the concentrations of gastrin, secretin and cholecystokinin in the patients much more than in the controls. Some differences in changes of the blood concentration of peptides were noted with regard to a type of test breakfast. However differentiated reactions of the endocrine apparatus of the gastroduodenal complex in response to the breakfasts were not a reliable functional and diagnostic criterion

  8. Pulse Arrival Time Based Cuff-Less and 24-H Wearable Blood Pressure Monitoring and its Diagnostic Value in Hypertension.

    Science.gov (United States)

    Zheng, Yali; Poon, Carmen C Y; Yan, Bryan P; Lau, James Y W

    2016-09-01

    Ambulatory blood pressure monitoring (ABPM) has become an essential tool in the diagnosis and management of hypertension. Current standard ABPM devices use an oscillometric cuff-based method which can cause physical discomfort to the patients with repeated inflations and deflations, especially during nighttime leading to sleep disturbance. The ability to measure ambulatory BP accurately and comfortably without a cuff would be attractive. This study validated the accuracy of a cuff-less approach for ABPM using pulse arrival time (PAT) measurements on both healthy and hypertensive subjects for potential use in hypertensive management, which is the first of its kind. The wearable cuff-less device was evaluated against a standard cuff-based device on 24 subjects of which 15 have known hypertension. BP measurements were taken from each subject over a 24-h period by the cuff-less and cuff-based devices every 15 to 30 minutes during daily activities. Mean BP of each subject during daytime, nighttime and over 24-h were calculated. Agreement between mean nighttime systolic BP (SBP) and diastolic (DBP) measured by the two devices evaluated using Bland-Altman plot were -1.4 ± 6.6 and 0.4 ± 6.7 mmHg, respectively. Receiver operator characteristics (ROC) statistics was used to assess the diagnostic accuracy of the cuff-less approach in the detection of BP above the hypertension threshold during nighttime (>120/70 mmHg). The area under ROC curves were 0.975/0.79 for nighttime. The results suggest that PAT-based approach is accurate and promising for ABPM without the issue of sleep disturbances associated with cuff-based devices. PMID:27447469

  9. Rapid detection of hemagglutination using restrictive microfluidic channels equipped with waveguide-mode sensors

    Science.gov (United States)

    Ashiba, Hiroki; Fujimaki, Makoto; Awazu, Koichi; Fu, Mengying; Ohki, Yoshimichi; Tanaka, Torahiko; Makishima, Makoto

    2016-02-01

    Hemagglutination is utilized for various immunological assays, including blood typing and virus detection. Herein, we describe a method of rapid hemagglutination detection based on a microfluidic channel installed on an optical waveguide-mode sensor. Human blood samples mixed with hemagglutinating antibodies associated with different blood groups were injected into the microfluidic channel, and reflectance spectra of the samples were measured after stopping the flow. The agglutinated and nonagglutinated samples were distinguishable by the alterations in their reflectance spectra with time; the microfluidic channels worked as spatial restraints for agglutinated red blood cells. The demonstrated system allowed rapid hemagglutination detection within 1 min. The suitable height of the channels was also discussed.

  10. Determining the Diagnostic Value of Mycobacterium Tuberculosis DNA in the Differentiation of Blood Samples of Patients with Active Pulmonary Tuberculosis and Healthy Controls Using Polymerase Chain Reaction

    OpenAIRE

    Abasali Niazi; Nezarali Muolai; Mosayeb Shahriar; Reza Karimian; Farzaneh Peykfalak

    2013-01-01

    Background: Tuberculosis (TB) is now a major cause of mortality and morbidity in the world. Nowadays, different methods are used to diagnose tuberculosis. Although classical microbiological methods (such as sputum smear) are specific, they have little sensitivity and the culture is also time-consuming. Using Polymerase Chain Reaction (PCR) in blood samples in terms of Mycobacterium tuberculosis DNA, this study examines diagnostic power of this test in the diagnosis of pulmonary tuberculosis c...

  11. Microalbuminuria in Subjects with no History of Diabetes Mellitus and Hypertension : The Relationship with Hyperglycemia and High Blood Pressure at Non-Diagnostic Level

    OpenAIRE

    Ishibashi, Fukashi; Ishida, Kazufumi; Takashina, Seiryo

    1990-01-01

    1969 subjects underwent albumin index [A.I., urine microalbumin (mg/liter)/creatinine (g/liter)] in early morning urine, 75 g oral glucose tolerance test (OGTT), determination of plasma lipids (total cholesterol, triglyceride and high density lipoprotein-cholesterol) and a resting electrocardiogram. There was no history of treatment for diabetes mellitus and hypertension. The relationship between microalbuminuria, and hyperglycemia or high blood pressure at non-diagnostic level was examined. ...

  12. Measuring Post-Partum Haemorrhage in Low-Resource Settings: The Diagnostic Validity of Weighed Blood Loss versus Quantitative Changes in Hemoglobin

    Science.gov (United States)

    Atukunda, Esther Cathyln; Mugyenyi, Godfrey Rwambuka; Obua, Celestino; Atuhumuza, Elly Bronney; Musinguzi, Nicholas; Tornes, Yarine Fajardo; Agaba, Amon Ganaafa; Siedner, Mark Jacob

    2016-01-01

    Background Accurate estimation of blood loss is central to prompt diagnosis and management of post-partum hemorrhage (PPH), which remains a leading cause of maternal mortality in low-resource countries. In such settings, blood loss is often estimated visually and subjectively by attending health workers, due to inconsistent availability of laboratory infrastructure. We evaluated the diagnostic accuracy of weighed blood loss (WBL) versus changes in peri-partum hemoglobin to detect PPH. Methods Data from this analysis were collected as part of a randomized controlled trial comparing oxytocin with misoprostol for PPH (NCT01866241). Blood samples for complete blood count were drawn on admission and again prior to hospital discharge or before blood transfusion. During delivery, women were placed on drapes and had pre-weighed sanitary towels placed around their perineum. Blood was then drained into a calibrated container and the sanitary towels were added to estimate WBL, where each gram of blood was estimated as a milliliter. Sensitivity, specificity, negative and positive predictive values (PPVs) were calculated at various blood volume loss and time combinations, and we fit receiver-operator curves using blood loss at 1, 2, and 24 hours compared to a reference standard of haemoglobin decrease of >10%. Results A total of 1,140 women were enrolled in the study, of whom 258 (22.6%) developed PPH, defined as a haemoglobin drop >10%, and 262 (23.0%) had WBL ≥500mL. WBL generally had a poor sensitivity for detection of PPH (85%) in high prevalence settings when WBL exceeds 750mL. Conclusion WBL has poor sensitivity but high specificity compared to laboratory-based methods of PPH diagnosis. These characteristics correspond to a high PPV in areas with high PPH prevalence. Although WBL is not useful for excluding PPH, this low-cost, simple and reproducible method is promising as a reasonable method to identify significant PPH in such settings where quantifiable red cell

  13. Synthesis of digital microfluidic biochips

    OpenAIRE

    SCHWARZMANN, ANŽE

    2014-01-01

    This bachelor’s thesis presents a digital microfluidic biochip that is intended for carrying out tests on various human and environmental fluids. The predecessor of the digital microfluidic biochip is the continuous-flow microfluidic biochip, which is based on mechanical components for fluid movement. The basis for developing microfluidic biochips is microfluidics and the lab-on-a-chip, which make possible small biochips and device portability. This thesis presents sequential steps of synthes...

  14. Diagnostic utility of LunX mRNA in peripheral blood and pleural fluid in patients with primary non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Tian Zhigang

    2008-05-01

    Full Text Available Abstract Background Progress in lung cancer is hampered by the lack of clinically useful diagnostic markers. The goal of this study was to provide a detailed evaluation of lung cancer tumor markers indicative of molecular abnormalities and to assess their diagnostic utility in non-small cell lung cancer (NSCLC patients. Methods Quantitative real-time RT-PCR was used to determine LunX, CK19, CEA, VEGF-C and hnRNP A2/B1 mRNA levels in peripheral blood and pleural fluid from NSCLC patients, compared with those from patients with other epithelial cancer (esophagus cancer and breast cancer, benign lung disease (pneumonia and tuberculo pleurisy and from healthy volunteers. Results In peripheral blood LunX mRNA was detectable in 75.0% (33/44 of patients with NSCLC, but not in patients with other epithelial cancer (0/28, benign lung disease (0/10 or in healthy volunteers (0/15. In contrast, all other genetic markers were detected in patients with either NSCLC, other epithelia cancer or benign lung disease, and in healthy volunteers. The expression level and positive rate of LunX mRNA in peripheral blood correlated with the pathologic stage of NSCLC (P LunX mRNA was detected in 92.9% (13/14 of malignant pleural fluid samples and was the only marker whose expression level was significantly different between malignant and benign pleural fluid (P LunX mRNA in the peripheral blood of NSCLC patients decreased shortly after clinical treatment (P = 0.005. Conclusion Of several commonly used genetic markers, LunX mRNA is the most specific gene marker for lung cancer and has potential diagnostic utility when measured in the peripheral blood and pleural fluid of NSCLC patients.

  15. Construction of programmable interconnected 3D microfluidic networks

    Science.gov (United States)

    Hunziker, Patrick R.; Wolf, Marc P.; Wang, Xueya; Zhang, Bei; Marsch, Stephan; Salieb-Beugelaar, Georgette B.

    2015-02-01

    Microfluidic systems represent a key-enabling platform for novel diagnostic tools for use at the point-of-care in clinical contexts as well as for evolving single cell diagnostics. The design of 3D microfluidic systems is an active field of development, but construction of true interconnected 3D microfluidic networks is still a challenge, in particular when the goal is rapid prototyping, accurate design and flexibility. We report a novel approach for the construction of programmable 3D microfluidic systems consisting of modular 3D template casting of interconnected threads to allow user-programmable flow paths and examine its structural characteristics and its modular function. To overcome problems with thread template casting reported in the literature, low-surface-energy polymer threads were used, that allow solvent-free production. Connected circular channels with excellent roundness and low diameter variability were created. Variable channel termination allowed programming a flow path on-the-fly, thus rendering the resulting 3D microfluidic systems highly customizable even after production. Thus, construction of programmable/reprogrammable fully 3D microfluidic systems by template casting of a network of interconnecting threads is feasible, leads to high-quality and highly reproducible, complex 3D geometries.

  16. Construction of programmable interconnected 3D microfluidic networks

    International Nuclear Information System (INIS)

    Microfluidic systems represent a key-enabling platform for novel diagnostic tools for use at the point-of-care in clinical contexts as well as for evolving single cell diagnostics. The design of 3D microfluidic systems is an active field of development, but construction of true interconnected 3D microfluidic networks is still a challenge, in particular when the goal is rapid prototyping, accurate design and flexibility. We report a novel approach for the construction of programmable 3D microfluidic systems consisting of modular 3D template casting of interconnected threads to allow user-programmable flow paths and examine its structural characteristics and its modular function. To overcome problems with thread template casting reported in the literature, low-surface-energy polymer threads were used, that allow solvent-free production. Connected circular channels with excellent roundness and low diameter variability were created. Variable channel termination allowed programming a flow path on-the-fly, thus rendering the resulting 3D microfluidic systems highly customizable even after production. Thus, construction of programmable/reprogrammable fully 3D microfluidic systems by template casting of a network of interconnecting threads is feasible, leads to high-quality and highly reproducible, complex 3D geometries. (paper)

  17. Investigation of hot roller embossing for microfluidic devices

    International Nuclear Information System (INIS)

    Microfluidics for most bio-related diagnostic applications typically requires single usage disposable chips to avoid bio-fouling and cross-contamination. Individual piece-wise manufacturing of polymeric microfluidic devices has been widely employed in recent years. To significantly lower the manufacturing costs, one possible way is to improve the production yield of polymer microfluidic chips via the hot roller embossing method. This paper discusses the effects of varying the process parameters such as roller temperature, applied pressure and substrate preheating during hot roller embossing (according to a systematic set of experiment designs) and its influence on the corresponding mold to pattern fidelity in terms of normalized embossed depths on the poly(methylmethacrylate) (PMMA) substrate. Concurrently, pattern density studies on the mold were also conducted. Functional testing in terms of fluid flow and micromixing was carried out to evaluate the feasibility of using hot roller embossed PMMA substrates as microfluidic chips

  18. Opto-Microfluidic Immunosensors: From Colorimetric to Plasmonic

    Directory of Open Access Journals (Sweden)

    Jie-Long He

    2016-02-01

    Full Text Available Optical detection has long been the most popular technique in immunosensing. Recent developments in the synthesis of luminescent probes and the fabrication of novel nanostructures enable more sensitive and efficient optical detection, which can be miniaturized and integrated with microfluidics to realize compact lab-on-a-chip immunosensors. These immunosensors are portable, economical and automated, but their sensitivity is not compromised. This review focuses on the incorporation and implementation of optical detection and microfluidics in immunosensors; it introduces the working principles of each optical detection technique and how it can be exploited in immunosensing. The recent progress in various opto-microfluidic immunosensor designs is described. Instead of being comprehensive to include all opto-microfluidic platforms, the report centers on the designs that are promising for point-of-care immunosensing diagnostics, in which ease of use, stability and cost-effective fabrication are emphasized.

  19. Diagnostic values for the viral load in peripheral blood mononuclear cells of patients with chronic active Epstein-Barr virus disease.

    Science.gov (United States)

    Ito, Yoshinori; Suzuki, Michio; Kawada, Jun-Ichi; Kimura, Hiroshi

    2016-04-01

    Chronic active Epstein-Barr virus disease (CAEBV) is a distinct EBV-associated lymphoproliferative disease with a poor prognosis. Although the viral load in blood samples has been widely used for diagnosing CAEBV, well-defined viral load thresholds to guide clinicians are currently lacking. The aim of the present study was to determine standardized diagnostic values for EBV load in blood samples of CAEBV patients using the World Health Organization international standard for reporting. Levels of EBV DNA in 103 peripheral blood mononuclear cells (PBMCs) and 95 plasma/serum samples from 107 cases with CAEBV were quantified and expressed in international units. Receiver operating characteristic curves were analyzed to assess the most appropriate cut-off values for levels of EBV DNA to distinguish CAEBV from EBV-associated infectious mononucleosis (IM) and controls with past EBV infection. Levels of EBV DNA in PBMCs were significantly higher in the CAEBV group (median, 10(4.2) IU/μgDNA) compared to the IM (median, 10(2.1) IU/μgDNA) and control groups. An inconsistent qualitative result was seen in 13 of 86 CAEBV patients; in these, EBV-DNA was positive in PBMCs, but negative in plasma. Diagnostic cut-off values for viral load in PBMCs from CAEBV patients, as compared to those of healthy controls and IM patients, were 10(2.0) IU/μgDNA and 10(3.2) IU/μgDNA, respectively. For diagnostic purposes, the viral load of PBMCs was better than of plasma/serum. A diagnostic cut-off EBV load for CAEBV may be useful for the management of CAEBV patients. PMID:26712582

  20. Cell manipulation in microfluidics

    International Nuclear Information System (INIS)

    Recent advances in the lab-on-a-chip field in association with nano/microfluidics have been made for new applications and functionalities to the fields of molecular biology, genetic analysis and proteomics, enabling the expansion of the cell biology field. Specifically, microfluidics has provided promising tools for enhancing cell biological research, since it has the ability to precisely control the cellular environment, to easily mimic heterogeneous cellular environment by multiplexing, and to analyze sub-cellular information by high-contents screening assays at the single-cell level. Various cell manipulation techniques in microfluidics have been developed in accordance with specific objectives and applications. In this review, we examine the latest achievements of cell manipulation techniques in microfluidics by categorizing externally applied forces for manipulation: (i) optical, (ii) magnetic, (iii) electrical, (iv) mechanical and (v) other manipulations. We furthermore focus on history where the manipulation techniques originate and also discuss future perspectives with key examples where available. (topical review)

  1. Microfluidic chemical reaction circuits

    Science.gov (United States)

    Lee, Chung-cheng; Sui, Guodong; Elizarov, Arkadij; Kolb, Hartmuth C.; Huang, Jiang; Heath, James R.; Phelps, Michael E.; Quake, Stephen R.; Tseng, Hsian-rong; Wyatt, Paul; Daridon, Antoine

    2012-06-26

    New microfluidic devices, useful for carrying out chemical reactions, are provided. The devices are adapted for on-chip solvent exchange, chemical processes requiring multiple chemical reactions, and rapid concentration of reagents.

  2. Microfluidic CARS cytometry

    OpenAIRE

    Wang, Han-Wei; Bao, Ning; Le, Thuc T.; Lu, Chang; Cheng, Ji-Xin

    2008-01-01

    Coherent anti-stokes Raman scattering (CARS) flow cytometry was demonstrated by combining a laser-scanning CARS microscope with a polydimethylsiloxane (PDMS) based microfluidic device. Line-scanning across the hydrodynamically focused core stream was performed for detection of flowing objects. Parameters were optimized by utilizing polystyrene beads as flowing particles. Population measurements of adipocytes isolated from mouse fat tissues demonstrated the viability of microfluidic CARS cytom...

  3. Designer emulsions using microfluidics

    OpenAIRE

    Rhutesh K. Shah; Ho Cheung Shum; Amy C. Rowat; Daeyeon Lee; Agresti, Jeremy J.; Andrew S. Utada; Liang-Yin Chu; Jin-Woong Kim; Alberto Fernandez-Nieves; Carlos J. Martinez; Weitz, David A.

    2008-01-01

    We describe new developments for the controlled fabrication of monodisperse emulsions using microfluidics. We use glass capillary devices to generate single, double, and higher order emulsions with exceptional precision. These emulsions can serve as ideal templates for generating well-defined particles and functional vesicles. Polydimethylsiloxane microfluidic devices are also used to generate picoliter-scale water-in-oil emulsions at rates as high as 10 000 drops per second. These emulsions ...

  4. High-Pressure Microfluidics

    OpenAIRE

    Ogden, Sam

    2013-01-01

    In this thesis, some fundamentals and possible applications of high-pressure microfluidics have been explored. Furthermore, handling fluids at high pressures has been addressed, specifically by creating and characterizing strong microvalves and pumps. A variety of microstructuring techniques was used to realize these microfluidic devices, e.g., etching, lithography, and bonding. To be able to handle high pressures, the valves and pumps need to be strong. This necessitates a strong actuator ma...

  5. MEMS in microfluidic channels.

    Energy Technology Data Exchange (ETDEWEB)

    Ashby, Carol Iris Hill; Okandan, Murat; Michalske, Terry A.; Sounart, Thomas L.; Matzke, Carolyn M.

    2004-03-01

    Microelectromechanical systems (MEMS) comprise a new class of devices that include various forms of sensors and actuators. Recent studies have shown that microscale cantilever structures are able to detect a wide range of chemicals, biomolecules or even single bacterial cells. In this approach, cantilever deflection replaces optical fluorescence detection thereby eliminating complex chemical tagging steps that are difficult to achieve with chip-based architectures. A key challenge to utilizing this new detection scheme is the incorporation of functionalized MEMS structures within complex microfluidic channel architectures. The ability to accomplish this integration is currently limited by the processing approaches used to seal lids on pre-etched microfluidic channels. This report describes Sandia's first construction of MEMS instrumented microfluidic chips, which were fabricated by combining our leading capabilities in MEMS processing with our low-temperature photolithographic method for fabricating microfluidic channels. We have explored in-situ cantilevers and other similar passive MEMS devices as a new approach to directly sense fluid transport, and have successfully monitored local flow rates and viscosities within microfluidic channels. Actuated MEMS structures have also been incorporated into microfluidic channels, and the electrical requirements for actuation in liquids have been quantified with an elegant theory. Electrostatic actuation in water has been accomplished, and a novel technique for monitoring local electrical conductivities has been invented.

  6. Microfluidic integration for automated targeted proteomic assays.

    Science.gov (United States)

    Hughes, Alex J; Lin, Robert K C; Peehl, Donna M; Herr, Amy E

    2012-04-17

    A dearth of protein isoform-based clinical diagnostics currently hinders advances in personalized medicine. A well-organized protein biomarker validation process that includes facile measurement of protein isoforms would accelerate development of effective protein-based diagnostics. Toward scalable protein isoform analysis, we introduce a microfluidic "single-channel, multistage" immunoblotting strategy. The multistep assay performs all immunoblotting steps: separation, immobilization of resolved proteins, antibody probing of immobilized proteins, and all interim wash steps. Programmable, low-dispersion electrophoretic transport obviates the need for pumps and valves. A three-dimensional bulk photoreactive hydrogel eliminates manual blotting. In addition to simplified operation and interfacing, directed electrophoretic transport through our 3D nanoporous reactive hydrogel yields superior performance over the state-of-the-art in enhanced capture efficiency (on par with membrane electroblotting) and sparing consumption of reagents (ca. 1 ng antibody), as supported by empirical and by scaling analyses. We apply our fully integrated microfluidic assay to protein measurements of endogenous prostate specific antigen isoforms in (i) minimally processed human prostate cancer cell lysate (1.1 pg limit of detection) and (ii) crude sera from metastatic prostate cancer patients. The single-instrument functionality establishes a scalable microfluidic framework for high-throughput targeted proteomics, as is relevant to personalized medicine through robust protein biomarker verification, systematic characterization of new antibody probes for functional proteomics, and, more broadly, to characterization of human biospecimen repositories. PMID:22474344

  7. Isolation of cancer cells by "in situ" microfluidic biofunctionalization protocols

    DEFF Research Database (Denmark)

    De Vitis, Stefania; Matarise, Giuseppina; Pardeo, Francesca;

    2014-01-01

    The aim of this work is the development of a microfluidic immunosensor for the immobilization of cancer cells and their separation from healthy cells by using "in situ" microfluidic biofunctionalization protocols. These protocols allow to link antibodies on microfluidic device surfaces and can be...... used to study the interaction between cell membrane and biomolecules. Moreover they allow to perform analysis with high processing speed, small quantity of reagents and samples, short reaction times and low production costs. In this work the developed protocols were used in microfluidic devices for the...... isolation of cancer cells in heterogeneous blood samples by exploiting the binding of specific antibody to an adhesion protein (EpCAM), overexpressed on the tumor cell membranes. The presented biofunctionalization protocols can be performed right before running the experiment: this allows to have a flexible...

  8. Impact of the phlebotomy training based on CLSI/NCCLS H03-A6 - procedures for the collection of diagnostic blood specimens by venipuncture.

    Science.gov (United States)

    Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Picheth, Geraldo; Guidi, Gian Cesare

    2012-01-01

    Introduction: The activities involving phlebotomy, a critical task for obtaining diagnostic blood samples, are poorly studied as regards the major sources of errors and the procedures related to laboratory quality control. The aim of this study was to verify the compliance with CLSI documents of clinical laboratories from South America and to assess whether teaching phlebotomists to follow the exact procedure for blood collection by venipuncture from CLSI/NCCLS H03-A6 - Procedures for the Collection of Diagnostic Blood Specimens by Venipuncture might improve the quality of the process. Materials and methods: A survey was sent by mail to 3674 laboratories from South America to verify the use of CLSI documents. Thirty skilled phlebotomists were trained with the CLSI H03-A6 document to perform venipuncture procedures for a period of 20 consecutive working days. The overall performances of the phlebotomists were further compared before and after the training program. Results: 2622 from 2781 laboratories that did answer our survey used CLSI documents to standardize their procedures and process. The phlebotomists’ training for 20 days before our evaluation completely eliminated non-conformity procedures for: i) incorrect friction of the forearm, during the cleaning of the venipuncture site to ease vein location; ii) incorrect sequence of vacuum tubes collection; and iii) inadequate mixing of the blood in primary vacuum tubes containing anticoagulants or clot activators. Unfortunately the CLSI H03-A6 document does not caution against both unsuitable tourniquet application time (i.e., for more than one minute) and inappropriate request to clench the fist repeatedly. These inadequate procedures were observed for all phlebotomists. Conclusion: We showed that strict observance of the CLSI H03-A6 document can remarkably improve quality, although the various steps for collecting diagnostic blood specimens are not a gold standard, since they may still permit errors. Tourniquet

  9. Superparamagnetic-bead Based Method: An Effective DNA Extraction from Dried Blood Spots (DBS) for Diagnostic PCR

    OpenAIRE

    Sirdah, Mahmoud Mohammed

    2014-01-01

    Introduction: Storing blood as dried spots on filter paper is a trustworthy approach used in genetic screening issues which justifies the necessity for a reliable DNA extraction method. The present work aims to investigate the effectiveness of superparamagnetic-bead based method in extracting DNA from dried blood spots (DBS).

  10. On-chip Extraction of Intracellular Molecules in White Blood Cells from Whole Blood

    Science.gov (United States)

    Choi, Jongchan; Hyun, Ji-Chul; Yang, Sung

    2015-10-01

    The extraction of virological markers in white blood cells (WBCs) from whole blood—without reagents, electricity, or instruments—is the most important first step for diagnostic testing of infectious diseases in resource-limited settings. Here we develop an integrated microfluidic chip that continuously separates WBCs from whole blood and mechanically ruptures them to extract intracellular proteins and nucleic acids for diagnostic purposes. The integrated chip is assembled with a device that separates WBCs by using differences in blood cell size and a mechanical cell lysis chip with ultra-sharp nanoblade arrays. We demonstrate the performance of the integrated device by quantitatively analyzing the levels of extracted intracellular proteins and genomic DNAs. Our results show that compared with a conventional method, the device yields 120% higher level of total protein amount and similar levels of gDNA (90.3%). To demonstrate its clinical application to human immunodeficiency virus (HIV) diagnostics, the developed chip was used to process blood samples containing HIV-infected cells. Based on PCR results, we demonstrate that the chip can extract HIV proviral DNAs from infected cells with a population as low as 102/μl. These findings suggest that the developed device has potential application in point-of-care testing for infectious diseases in developing countries.

  11. Microfluidic tectonics: A comprehensive construction platform for microfluidic systems

    OpenAIRE

    Beebe, David J.; Moore, Jeffrey S.; Yu, Qing; Liu, Robin H.; Kraft, Mary L.; Jo, Byung-Ho; Devadoss, Chelladurai

    2000-01-01

    A microfluidic platform for the construction of microscale components and autonomous systems is presented. The platform combines liquid-phase photopolymerization, lithography, and laminar flow to allow the creation of complex and autonomous microfluidic systems. The fabrication of channels, actuators, valves, sensors, and systems is demonstrated. Construction times can be as short as 10 min, providing ultrarapid prototyping of microfluidic systems.

  12. Advances in microfluidics in combating infectious diseases.

    Science.gov (United States)

    Tay, Andy; Pavesi, Andrea; Yazdi, Saeed Rismani; Lim, Chwee Teck; Warkiani, Majid Ebrahimi

    2016-01-01

    One of the important pursuits in science and engineering research today is to develop low-cost and user-friendly technologies to improve the health of people. Over the past decade, research efforts in microfluidics have been made to develop methods that can facilitate low-cost diagnosis of infectious diseases, especially in resource-poor settings. Here, we provide an overview of the recent advances in microfluidic devices for point-of-care (POC) diagnostics for infectious diseases and emphasis is placed on malaria, sepsis and AIDS/HIV. Other infectious diseases such as SARS, tuberculosis, and dengue are also briefly discussed. These infectious diseases are chosen as they contribute the most to disability-adjusted life-years (DALYs) lost according to the World Health Organization (WHO). The current state of research in this area is evaluated and projection toward future applications and accompanying challenges are also discussed. PMID:26854743

  13. IFSA: a microfluidic chip-platform for frit-based immunoassay protocols

    Science.gov (United States)

    Hlawatsch, Nadine; Bangert, Michael; Miethe, Peter; Becker, Holger; Gärtner, Claudia

    2013-03-01

    Point-of-care diagnostics (POC) is one of the key application fields for lab-on-a-chip devices. While in recent years much of the work has concentrated on integrating complex molecular diagnostic assays onto a microfluidic device, there is a need to also put comparatively simple immunoassay-type protocols on a microfluidic platform. In this paper, we present the development of a microfluidic cartridge using an immunofiltration approach. In this method, the sandwich immunoassay takes place in a porous frit on which the antibodies have immobilized. The device is designed to be able to handle three samples in parallel and up to four analytical targets per sample. In order to meet the critical cost targets for the diagnostic market, the microfluidic chip has been designed and manufactured using high-volume manufacturing technologies in mind. Validation experiments show comparable sensitivities in comparison with conventional immunofiltration kits.

  14. Comparison of serum, salivary, and rapid whole blood diagnostic tests for Helicobacter pylori and their validation against endoscopy based tests.

    OpenAIRE

    Reilly, T G; Poxon, V; Sanders, D S; Elliott, T S; Walt, R P

    1997-01-01

    BACKGROUND: A rapid, reliable, and accurate test for the diagnosis of infection with Helicobacter pylori is needed for screening dyspeptic patients before referral for endoscopy. AIM: To compare a new rapid whole blood test (Helisal rapid blood, Cortecs), two serum enzyme linked immunosorbent assays (ELISAs; Helico-G, Shield and Helisal serum, Cortecs), and a salivary assay (Helisal saliva, Cortecs), with slide biopsy urease, 13C-urea breath test, and histology. METHODS: Three hundred and thr...

  15. Microfluidic Flame Barrier

    Science.gov (United States)

    Mungas, Gregory S. (Inventor); Fisher, David J. (Inventor); Mungas, Christopher (Inventor)

    2013-01-01

    Propellants flow through specialized mechanical hardware that is designed for effective and safe ignition and sustained combustion of the propellants. By integrating a micro-fluidic porous media element between a propellant feed source and the combustion chamber, an effective and reliable propellant injector head may be implemented that is capable of withstanding transient combustion and detonation waves that commonly occur during an ignition event. The micro-fluidic porous media element is of specified porosity or porosity gradient selected to be appropriate for a given propellant. Additionally the propellant injector head design integrates a spark ignition mechanism that withstands extremely hot running conditions without noticeable spark mechanism degradation.

  16. Droplet microfluidics for microbiology: techniques, applications and challenges.

    Science.gov (United States)

    Kaminski, Tomasz S; Scheler, Ott; Garstecki, Piotr

    2016-06-21

    Droplet microfluidics has rapidly emerged as one of the key technologies opening up new experimental possibilities in microbiology. The ability to generate, manipulate and monitor droplets carrying single cells or small populations of bacteria in a highly parallel and high throughput manner creates new approaches for solving problems in diagnostics and for research on bacterial evolution. This review presents applications of droplet microfluidics in various fields of microbiology: i) detection and identification of pathogens, ii) antibiotic susceptibility testing, iii) studies of microbial physiology and iv) biotechnological selection and improvement of strains. We also list the challenges in the dynamically developing field and new potential uses of droplets in microbiology. PMID:27212581

  17. Thirty years of research on diagnostic and therapeutic thresholds for the self-measured blood pressure at home.

    NARCIS (Netherlands)

    Staessen, J.A.; Thijs, L.; Ohkubo, T.; Kikuya, M.; Richart, T.; Boggia, J.; Adiyaman, A.; Dechering, D.G.; Kuznetsova, T.; Thien, Th.; Leeuw, P de; Imai, Y.; O'brien, E.; Parati, G.

    2008-01-01

    OBJECTIVE: The goal of this review study is to summarize 30 years of research on cut-off limits for the self-measured blood pressure. METHODS: We reviewed two meta-analyses, several prospective outcome studies in populations and hypertensive patients, studies in pregnant women, three clinical trials

  18. 3D origami-based multifunction-integrated immunodevice: low-cost and multiplexed sandwich chemiluminescence immunoassay on microfluidic paper-based analytical device.

    Science.gov (United States)

    Ge, Lei; Wang, Shoumei; Song, Xianrang; Ge, Shenguang; Yu, Jinghua

    2012-09-01

    A novel 3D microfluidic paper-based immunodevice, integrated with blood plasma separation from whole blood samples, automation of rinse steps, and multiplexed CL detections, was developed for the first time based on the principle of origami (denoted as origami-based device). This 3D origami-based device, comprised of one test pad surrounded by four folding tabs, could be patterned and fabricated by wax-printing on paper in bulk. In this work, a sandwich-type chemiluminescence (CL) immunoassay was introduced into this 3D origami-based immunodevice, which could separate the operational procedures into several steps including (i) folding pads above/below and (ii) addition of reagent/buffer under a specific sequence. The CL behavior, blood plasma separation, washing protocol, and incubation time were investigated in this work. The developed 3D origami-based CL immunodevice, combined with a typical luminuol-H(2)O(2) CL system and catalyzed by Ag nanoparticles, showed excellent analytical performance for the simultaneous detection of four tumor markers. The whole blood samples were assayed and the results obtained were in agreement with the reference values from the parallel single-analyte test. This paper-based microfluidic origami CL detection system provides a new strategy for a low-cost, sensitive, simultaneous multiplex immunoassay and point-of-care diagnostics. PMID:22763468

  19. Flexible opto-electronics enabled microfluidics systems with cloud connectivity for point-of-care micronutrient analysis.

    Science.gov (United States)

    Lee, Stephen; Aranyosi, A J; Wong, Michelle D; Hong, Ji Hyung; Lowe, Jared; Chan, Carol; Garlock, David; Shaw, Scott; Beattie, Patrick D; Kratochvil, Zachary; Kubasti, Nick; Seagers, Kirsten; Ghaffari, Roozbeh; Swanson, Christina D

    2016-04-15

    In developing countries, the deployment of medical diagnostic technologies remains a challenge because of infrastructural limitations (e.g. refrigeration, electricity), and paucity of health professionals, distribution centers and transportation systems. Here we demonstrate the technical development and clinical testing of a novel electronics enabled microfluidic paper-based analytical device (EE-μPAD) for quantitative measurement of micronutrient concentrations in decentralized, resource-limited settings. The system performs immune-detection using paper-based microfluidics, instrumented with flexible electronics and optoelectronic sensors in a mechanically robust, ultrathin format comparable in size to a credit card. Autonomous self-calibration, plasma separation, flow monitoring, timing and data storage enable multiple devices to be run simultaneously. Measurements are wirelessly transferred to a mobile phone application that geo-tags the data and transmits it to a remote server for real time tracking of micronutrient deficiencies. Clinical tests of micronutrient levels from whole blood samples (n=95) show comparable sensitivity and specificity to ELISA-based tests. These results demonstrate instantaneous acquisition and global aggregation of diagnostics data using a fully integrated point of care system that will enable rapid and distributed surveillance of disease prevalence and geographical progression. PMID:26630284

  20. Enzyme detection by microfluidics

    DEFF Research Database (Denmark)

    2013-01-01

    Microfluidic-implemented methods of detecting an enzyme, in particular a DNA-modifying enzyme, are provided, as well as methods for detecting a cell, or a microorganism expressing said enzyme. The enzyme is detected by providing a nucleic acid substrate, which is specifically targeted by that...... enzyme...

  1. Miniaturization and microfluidics

    Czech Academy of Sciences Publication Activity Database

    Foret, František; Smejkal, Petr; Macka, M.

    Waltham, MA 02451: Elsevier, 2013, s. 453-467 ISBN 978-0-12-415807-8 R&D Projects: GA ČR(CZ) GAP301/11/2055 Institutional support: RVO:68081715 Keywords : miniaturization * microfluidics * HPLC systems * electrophoretic systems Subject RIV: CB - Analytical Chemistry, Separation

  2. Chemistry in Microfluidic Channels

    Science.gov (United States)

    Chia, Matthew C.; Sweeney, Christina M.; Odom, Teri W.

    2011-01-01

    General chemistry introduces principles such as acid-base chemistry, mixing, and precipitation that are usually demonstrated in bulk solutions. In this laboratory experiment, we describe how chemical reactions can be performed in a microfluidic channel to show advanced concepts such as laminar fluid flow and controlled precipitation. Three sets of…

  3. Basic Microfluidics Theory

    DEFF Research Database (Denmark)

    Svendsen, Winnie Edith

    2015-01-01

    ,000 m−1, which is a huge difference and has a large impact on flow behavior. In this chapter the basic microfluidic theory will be presented, enabling the reader to gain a comprehensive understanding of how liquids behave at the microscale, enough to be able to engage in design of micro systems and to...

  4. Assessment of diagnostic potency of exosomal microRNA in circulating blood of patient with thyroid cancer

    Directory of Open Access Journals (Sweden)

    R. B. Samsonov

    2015-11-01

    Full Text Available Diagnostics of thyroid cancer (TC remains a challenging issue due to the high incidence of asymptomatic thyroid nodular pathologies and absence of non-invasive methods of their assessment. Thyroid tumors are classified as benign and malignant with incidence ration approximated as 9:1. Correct and timely differential diagnosis is the basis for correctly choosing a treatment policy and hence determines treatment results. Methods for molecular genetic analysis are being recently developed and introduced into clinical practice, enabling the diagnostic process to be optimized. Analysis of the intracellular and secreted (exosomal fractions of small regulatory RNAs (microRNAs is one of the most promising methods for the diagnosis of cancers, including TC. The stability of extracellular microRNA is determined by bonds to proteins, lipoproteins, or its encapsulation into the membrane microvesicles – exosomes. There is reason for suggesting that exosomes with the specific composition of microRNA are a result of the process of active and biologically important secretion while release of other microRNA forms accompanies apoptotic or necrotic cell death. This determines the special diagnostic value of the exosomal fraction of circulating microRNAs, which may reflect the presence and clinically relevant properties of a tumor. This paper discusses the state of the problem and presents methods and preliminary results of the studies conducted by the authors to develop a novel method for diagnosing and monitoring TC. Thus, level of plasma exosomal miR-21 was shown to distinguish patients with benign tumor and follicular CT, while miR-31 can help to distinguish patients with benign tumor and papillary TC. Moreover, reciprocal character of miR-21 and miR-181a concentration in plasma exosomes was detected by comparison of patient with papillary and follicular TC.

  5. Magnetic permeability based diagnostic test for the determination of the canine C-reactive protein concentration in undiluted whole blood

    Energy Technology Data Exchange (ETDEWEB)

    Ibraimi, Filiz; Kriz, Kirstin [Department of Pure and Applied Biochemistry, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); LifeAssays AB, IDEON Science Park, SE-223 70 Lund (Sweden); Merin, Henrik [Malmoe Animal Hospital, P.O. Box 9090, SE-213 63 Malmoe (Sweden); Kriz, Dario [Department of Pure and Applied Biochemistry, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); LifeAssays AB, IDEON Science Park, SE-223 70 Lund (Sweden)], E-mail: dario.kriz@euris.org

    2009-05-15

    We describe an one-step 11-min magnetic permeability based two-site immunoassay for C-reactive protein (CRP) utilizing polyclonal anti-canine CRP antibody conjugated dextran iron oxide nanoparticles (79 nm) as superparamagnetic labels and polyclonal anti-canine CRP conjugated silica microparticles (15 to 40 {mu}m) as carriers. An inductance based magnetic permeability reader was used to detect the target analyte, CRP, in 10 {mu}L whole blood samples, by measuring the magnetic permeability increase of the silica microparticle sediment due to immuno complex superparamagnetic nanoparticles. Measurements on standards showed a linear response between 0 and 17.5 mg/L CRP. Measurements performed on 16 whole blood samples from mixed breeds showed good correlation with a commercially available ELISA assay.

  6. Magnetic permeability based diagnostic test for the determination of the canine C-reactive protein concentration in undiluted whole blood

    International Nuclear Information System (INIS)

    We describe an one-step 11-min magnetic permeability based two-site immunoassay for C-reactive protein (CRP) utilizing polyclonal anti-canine CRP antibody conjugated dextran iron oxide nanoparticles (79 nm) as superparamagnetic labels and polyclonal anti-canine CRP conjugated silica microparticles (15 to 40 μm) as carriers. An inductance based magnetic permeability reader was used to detect the target analyte, CRP, in 10 μL whole blood samples, by measuring the magnetic permeability increase of the silica microparticle sediment due to immuno complex superparamagnetic nanoparticles. Measurements on standards showed a linear response between 0 and 17.5 mg/L CRP. Measurements performed on 16 whole blood samples from mixed breeds showed good correlation with a commercially available ELISA assay.

  7. Extensive surface protein profiles of extracellular vesicles from cancer cells may provide diagnostic signatures from blood samples

    OpenAIRE

    Belov, Larissa; Matic, Kieran J.; Hallal, Susannah; Mulligan, Stephen P.; Best, O. Giles; Christopherson, Richard I

    2016-01-01

    Extracellular vesicles (EV) are membranous particles (30–1,000 nm in diameter) secreted by cells. Important biological functions have been attributed to 2 subsets of EV, the exosomes (bud from endosomal membranes) and the microvesicles (MV; bud from plasma membranes). Since both types of particles contain surface proteins derived from their cell of origin, their detection in blood may enable diagnosis and prognosis of disease. We have used an antibody microarray (DotScan) to compare the surfa...

  8. Diagnostic imaging of musculoskeletal infection. Roentgenography; Gallium, indium-labeled white blood cell, gammaglobulin, bone scintigraphy; and MRI

    International Nuclear Information System (INIS)

    A great deal of effort has been made to evaluate and define the role of various diagnostic imaging techniques in various clinical settings that complicate the diagnosis of osteomyelitis. Except possibly in neonates, bone scintigraphy remains generally recommended when there has been no previous osseous involvement. In other cases of chronic disease, previous fracture or trauma, prosthesis, and diabetic foot, In-WBC scintigraphy is generally accepted as an appropriate imaging technique. MRI will play an increasingly important role in diagnosing osteomyelitis and may prove to be an important adjunct in these cases. Research continues to improve our current diagnostic armamentarium. In-IgG appears to avoid practical deficiencies encountered with 67Ga and In-WBC; it remains to be seen what role this agent will play in routine clinical practice. All agents to date image inflammation, not infection, and most require delayed imaging sessions, usually at 24 hours. These shortcomings necessitate further research to develop new radiotracers that can provide useful images within several hours and that are specific for infection, perhaps ultimately delineating the particular microorganism involved.84 references

  9. Numerical simulation of isolation of cancer cells in a microfluidic chip

    Science.gov (United States)

    Djukic, T.; Topalovic, M.; Filipovic, N.

    2015-08-01

    Cancer is a disease that is characterized by the uncontrolled increase of numbers of cells. Circulating tumour cells (CTCs) are separated from the primary tumor, circulate in the bloodstream and form metastases. Circulating tumor cells can be identified in the blood of a patient by taking a blood sample. Microfluidic chips are a new technique that is used to isolate these cells from the blood sample. In this paper a numerical model is presented that is able to simulate the motion of individual cells through a microfluidic chip. The proposed numerical model gives very valuable insight into the processes happening within a microfluidic chip. The accuracy of the proposed model is compared with experimental results. The experimental setup that is described in literature is used to create identical geometrical domains and define simulation parameters. A good agreement of experimental and numerical results demonstrates that the proposed model can be successfully used to simulate complex behaviour of CTCs inside microfluidic chips.

  10. Multiplexing slanted spiral microchannels for ultra-fast blood plasma separation.

    Science.gov (United States)

    Rafeie, Mehdi; Zhang, Jun; Asadnia, Mohsen; Li, Weihua; Warkiani, Majid Ebrahimi

    2016-08-01

    Blood and blood products are critical components of health care. Blood components perform distinct functions in the human body and thus the ability to efficiently fractionate blood into its individual components (i.e., plasma and cellular components) is of utmost importance for therapeutic and diagnostic purposes. Although conventional approaches like centrifugation and membrane filtration for blood processing have been successful in generating relatively pure fractions, they are largely limited by factors such as the required blood sample volume, component purity, clogging, processing time and operation efficiency. In this work, we developed a high-throughput inertial microfluidic system for cell focusing and blood plasma separation from small to large volume blood samples (1-100 mL). Initially, polystyrene beads and blood cells were used to investigate the inertial focusing performance of a single slanted spiral microchannel as a function of particle size, flow rate, and blood cell concentration. Afterwards, blood plasma separation was conducted using an optimised spiral microchannel with relatively large dimensions. It was found that the reject ratio of the slanted spiral channel is close to 100% for blood samples with haematocrit (HCT) values of 0.5% and 1% under an optimal flow rate of 1.5 mL min(-1). Finally, through a unique multiplexing approach, we built a high-throughput system consisting of 16 spiral channels connected together, which can process diluted samples with a total flow rate as high as 24 mL min(-1). The proposed multiplexed system can surmount the shortcomings of previously reported microfluidic systems for plasma separation and cell sorting in terms of throughput, yield and operation efficiency. PMID:27377196

  11. Intensely oscillating cavitation bubble in microfluidics

    Science.gov (United States)

    Siew-Wan, Ohl; Tandiono; Klaseboer, Evert; Dave, Ow; Choo, Andre; Claus-Dieter, Ohl

    2015-12-01

    This study reports the technical breakthrough in generating intense ultrasonic cavitation in the confinement of a microfluidics channel [1], and applications that has been developed on this platform for the past few years [2,3,4,5]. Our system consists of circular disc transducers (10-20 mm in diameter), the microfluidics channels on PDMS (polydimethylsiloxane), and a driving circuitry. The cavitation bubbles are created at the gas- water interface due to strong capillary waves which are generated when the system is driven at its natural frequency (around 100 kHz) [1]. These bubbles oscillate and collapse within the channel. The bubbles are useful for sonochemistry and the generation of sonoluminescence [2]. When we add bacteria (Escherichia coli), and yeast cells (Pichia pastoris) into the microfluidics channels, the oscillating and collapsing bubbles stretch and lyse these cells [3]. Furthermore, the system is effective (DNA of the harvested intracellular content remains largely intact), and efficient (yield reaches saturation in less than 1 second). In another application, human red blood cells are added to a microchamber. Cell stretching and rapture are observed when a laser generated cavitation bubble expands and collapses next to the cell [4]. A numerical model of a liquid pocket surrounded by a membrane with surface tension which was placed next to an oscillating bubble was developed using the Boundary Element Method. The simulation results showed that the stretching of the liquid pocket occurs only when the surface tension is within a certain range.

  12. [The diagnostics of adaptive reactions of blood on application the stress-modulating therapy in patients with brain chronic ischemia].

    Science.gov (United States)

    Krylov, V N; Deriugina, A V; Antipenko, E A; Zakharova, O A

    2012-12-01

    The article deals with the results of analysis of electrophoretic mobility of erythrocytes and leukogram in patients with dyscirculatory encephalopathy on different stages of disease on application therapy with inclusion of stress-modulating pharmaceuticals into course of treatment. It is established that the electrophoretic mobiliy of erythrocytes makes it possible to evaluate the adaptive indicators blood in patients with dyscirculatory encephalopathy. The consideration of these indicators makes feasible the substantiation of inclusion of stress-modulating therapy into complex treatment of patients with chronic cerebrovascular inefficiency. PMID:23479969

  13. Edwardsiella tarda Endocarditis Confirmed by Indium-111 White Blood Cell Scan: An Unusual Pathogen and Diagnostic Modality.

    Science.gov (United States)

    Litton, Kayleigh M; Rogers, Bret A

    2016-01-01

    Edwardsiella tarda is a freshwater marine member of the family Enterobacteriaceae which often colonizes fish, lizards, snakes, and turtles but is an infrequent human pathogen. Indium-111- ((111)In-) labeled white blood cell (WBC) scintigraphy is an imaging modality which has a wide range of reported sensitivity and specificity (from 60 to 100% and from 68 to 92%, resp.) for diagnosing acute and chronic infection. We describe a case of suspected E. tarda prosthetic aortic valve and mitral valve endocarditis with probable vegetations and new mitral regurgitation on transthoracic and transesophageal echocardiograms which was supported with the use of (111)In-labeled WBC scintigraphy. PMID:26885418

  14. Enhancing malaria diagnosis through microfluidic cell enrichment and magnetic resonance relaxometry detection

    Science.gov (United States)

    Fook Kong, Tian; Ye, Weijian; Peng, Weng Kung; Wei Hou, Han; Marcos; Preiser, Peter Rainer; Nguyen, Nam-Trung; Han, Jongyoon

    2015-06-01

    Despite significant advancements over the years, there remains an urgent need for low cost diagnostic approaches that allow for rapid, reliable and sensitive detection of malaria parasites in clinical samples. Our previous work has shown that magnetic resonance relaxometry (MRR) is a potentially highly sensitive tool for malaria diagnosis. A key challenge for making MRR based malaria diagnostics suitable for clinical testing is the fact that MRR baseline fluctuation exists between individuals, making it difficult to detect low level parasitemia. To overcome this problem, it is important to establish the MRR baseline of each individual while having the ability to reliably determine any changes that are caused by the infection of malaria parasite. Here we show that an approach that combines the use of microfluidic cell enrichment with a saponin lysis before MRR detection can overcome these challenges and provide the basis for a highly sensitive and reliable diagnostic approach of malaria parasites. Importantly, as little as 0.0005% of ring stage parasites can be detected reliably, making this ideally suited for the detection of malaria parasites in peripheral blood obtained from patients. The approaches used here are envisaged to provide a new malaria diagnosis solution in the near future.

  15. Fabrication of gravity-driven microfluidic device

    Science.gov (United States)

    Yamada, H.; Yoshida, Y.; Terada, N.; Hagihara, S.; Komatsu, T.; Terasawa, A.

    2008-12-01

    We have studied the micro total analysis system as a blood test. A microfluidic device with a three-pronged microchannel and artificial capillary vessels was fabricated. The microchannel is to transport blood, focus blood cells, and line them up. The vessels are to observe red blood cell deformation. An excimer laser was used to form grooves and so on. Numbers of thermosetting resin film and fluororesin were piled up on a cover glass. A laser fabricated part of the channel at the each film every lamination, and then a three-dimensional structure microchannel was fabricated. The channel sizes have widths of 50-150 μm and depths of 45 μm. Through holes used as artificial capillary vessels are made in the fluororesin having a minimum diameter of 5 μm and a length of 100 μm. As blood and a physiological saline are injected into the microchannel, the device stands upward facing the channel, and blood cells go into the vessels by the force of gravity and sheath flow of the saline. By gravity various groove patterns were made changing the width and length for measurement of blood focusing. Moreover, the red blood cell deformation was observed in the vessels with a microscope.

  16. Microfluidic vascular channels in gels using commercial 3D printers

    Science.gov (United States)

    Selvaganapathy, P. Ravi; Attalla, Rana

    2016-03-01

    This paper details the development of a three dimensional (3D) printing system with a modified microfluidic printhead used for the generation of complex vascular tissue scaffolds. The print-head features an integrated coaxial nozzle that allows the fabrication of hollow, calcium-polymerized alginate tubes that can easily be patterned using 3Dbioprinting techniques. This microfluidic design allows the incorporation of a wide range of scaffold materials as well as biological constituents such as cells, growth factors, and ECM material. With this setup, gel constructs with embedded arrays of hollow channels can be created and used as a potential substitute for blood vessel networks.

  17. Microfluidic device, and related methods

    Science.gov (United States)

    Wong, Eric W. (Inventor)

    2010-01-01

    A method of making a microfluidic device is provided. The method features patterning a permeable wall on a substrate, and surrounding the permeable wall with a solid, non-permeable boundary structure to establish a microfluidic channel having a cross-sectional dimension less than 5,000 microns and a cross-sectional area at least partially filled with the permeable wall so that fluid flowing through the microfluidic channel at least partially passes through the permeable wall.

  18. Whole-Teflon microfluidic chips

    OpenAIRE

    Ren, Kangning; Dai, Wen; Zhou, Jianhua; Su, Jing; Wu, Hongkai

    2011-01-01

    Although microfluidics has shown exciting potential, its broad applications are significantly limited by drawbacks of the materials used to make them. In this work, we present a convenient strategy for fabricating whole-Teflon microfluidic chips with integrated valves that show outstanding inertness to various chemicals and extreme resistance against all solvents. Compared with other microfluidic materials [e.g., poly(dimethylsiloxane) (PDMS)] the whole-Teflon chip has a few more advantages, ...

  19. Magnetic separation in microfluidic systems

    OpenAIRE

    Smistrup, Kristian; Hansen, Mikkel Fougt; Bruus, Henrik; Tang, Peter Torben; Kruhne, Ulrich Willi Walter

    2007-01-01

    This Ph.D. thesis presents theory, modeling, design, fabrication, experiments and results for microfluidic magnetic separators. A model for magnetic bead movement in a microfluidic channel is presented, and the limits of the model are discussed. The effective magnetic field gradient is defined, and it is argued that it is a good measure, when comparing the performance of magnetic bead separators. It is described how numeric modelling is used to aid the design of microfluidic magnetic separati...

  20. Microfluidic very large-scale integration for biochips: Technology, testing and fault-tolerant design

    DEFF Research Database (Denmark)

    Araci, Ismail Emre; Pop, Paul; Chakrabarty, Krishnendu

    2015-01-01

    paper is on continuous-flow biochips, where the basic building block is a microvalve. By combining these microvalves, more complex units such as mixers, switches, multiplexers can be built, hence the name of the technology, “microfluidic Very Large-Scale Integration” (mVLSI). A roadblock in the......Microfluidic biochips are replacing the conventional biochemical analyzers by integrating all the necessary functions for biochemical analysis using microfluidics. Biochips are used in many application areas, such as, in vitro diagnostics, drug discovery, biotech and ecology. The focus of this...

  1. Two-way FSI modelling of blood flow through CCA accounting on-line medical diagnostics in hypertension

    Science.gov (United States)

    Czechowicz, K.; Badur, J.; Narkiewicz, K.

    2014-08-01

    Flow parameters can induce pathological changes in the arteries. We propose a method to asses those parameters using a 3D computer model of the flow in the Common Carotid Artery. Input data was acquired using an automatic 2D ultrasound wall tracking system. This data has been used to generate a 3D geometry of the artery. The diameter and wall thickness have been assessed individually for every patient, but the artery has been taken as a 75mm straight tube. The Young's modulus for the arterial walls was calculated using the pulse pressure, diastolic (minimal) diameter and wall thickness (IMT). Blood flow was derived from the pressure waveform using a 2-parameter Windkessel model. The blood is assumed to be non-Newtonian. The computational models were generated and calculated using commercial code. The coupling method required the use of Arbitrary Lagrangian-Euler formulation to solve Navier-Stokes and Navier-Lame equations in a moving domain. The calculations showed that the distention of the walls in the model is not significantly different from the measurements. Results from the model have been used to locate additional risk factors, such as wall shear stress or circumferential stress, that may predict adverse hypertension complications.

  2. Two-way FSI modelling of blood flow through CCA accounting on-line medical diagnostics in hypertension

    International Nuclear Information System (INIS)

    Flow parameters can induce pathological changes in the arteries. We propose a method to asses those parameters using a 3D computer model of the flow in the Common Carotid Artery. Input data was acquired using an automatic 2D ultrasound wall tracking system. This data has been used to generate a 3D geometry of the artery. The diameter and wall thickness have been assessed individually for every patient, but the artery has been taken as a 75mm straight tube. The Young's modulus for the arterial walls was calculated using the pulse pressure, diastolic (minimal) diameter and wall thickness (IMT). Blood flow was derived from the pressure waveform using a 2-parameter Windkessel model. The blood is assumed to be non-Newtonian. The computational models were generated and calculated using commercial code. The coupling method required the use of Arbitrary Lagrangian-Euler formulation to solve Navier-Stokes and Navier-Lame equations in a moving domain. The calculations showed that the distention of the walls in the model is not significantly different from the measurements. Results from the model have been used to locate additional risk factors, such as wall shear stress or circumferential stress, that may predict adverse hypertension complications.

  3. A disposable, roll-to-roll hot-embossed inertial microfluidic device for size-based sorting of microbeads and cells.

    Science.gov (United States)

    Wang, Xiao; Liedert, Christina; Liedert, Ralph; Papautsky, Ian

    2016-05-21

    Inertial microfluidics has been a highly active area of research in recent years for high-throughput focusing and sorting of synthetic and biological microparticles. However, existing inertial microfluidic devices always rely on microchannels with high-aspect-ratio geometries (channel width w h) to achieve size-based sorting of microparticles and cells. The simple LAR geometry of the device enables successful high-throughput fabrication using R2R hot embossing. With optimized flow conditions and channel dimensions, we demonstrate continuous sorting of a mixture of 15 μm and 10 μm diameter microbeads with >97% sorting efficiency using the low-cost and disposable R2R chip. We further demonstrate size-based sorting of bovine white blood cells, demonstrating the ability to process real cellular samples in our R2R chip. We envision that this R2R hot-embossed inertial microfluidic chip will serve as a powerful yet low-cost and disposable tool for size-based sorting of synthetic microparticles in industrial applications or cellular samples in cell biology research and clinical diagnostics. PMID:27050341

  4. Determining the Diagnostic Value of Mycobacterium Tuberculosis DNA in the Differentiation of Blood Samples of Patients with Active Pulmonary Tuberculosis and Healthy Controls Using Polymerase Chain Reaction

    Directory of Open Access Journals (Sweden)

    Abasali Niazi

    2013-10-01

    Full Text Available Background: Tuberculosis (TB is now a major cause of mortality and morbidity in the world. Nowadays, different methods are used to diagnose tuberculosis. Although classical microbiological methods (such as sputum smear are specific, they have little sensitivity and the culture is also time-consuming. Using Polymerase Chain Reaction (PCR in blood samples in terms of Mycobacterium tuberculosis DNA, this study examines diagnostic power of this test in the diagnosis of pulmonary tuberculosis compared with other standard methods. Materials and Methods: In a cross-sectional descriptive-analytic study, blood samples were taken from 40 TB patients and 40 non-TB cases. Following DNA extraction by the commercial kit QIAGEN, the PCR assay was performed using IS6110 primer.Results: In this study, there were 80 people in two groups of TB and non-TB cases. Each group composed of 14 men (35% and 26 women (65%. Sensitivity, specificity as well as positive and negative predictive values obtained 37.5, 100, 100 and 61.5%, respectively.Conclusion: Despite high costs of using PCR for TB diagnosis, sensitivity of this method is low due to various factors and cannot replace current standard methods for TB diagnosis such as smear and culture. It can only be used as a complementary method to confirm diagnosis in strongly suspected cases of tuberculosis.

  5. Revisiting the white blood cell count: immature granulocytes count as a diagnostic marker to discriminate between SIRS and sepsis - a prospective, observational study

    Directory of Open Access Journals (Sweden)

    Nierhaus Axel

    2013-02-01

    Full Text Available Abstract Background Sepsis is a serious disease condition and a major cause of intensive care unit (ICU admission. Its diagnosis in critically ill patients is complicated. To diagnose an infection rapidly, and to accurately differentiate systemic inflammatory response syndrome (SIRS from sepsis, is challenging yet early diagnosis is vital for early induction of an appropriate therapy. The aim of this study was to evaluate whether the immature granulocyte (IG count is a useful early diagnostic marker of sepsis compared to other markers. Therefore, a total of 70 consecutive surgical intensive care patients were assessed. IGs were measured from whole blood samples using an automated analyzer. C-reactive protein (CRP, lipopolysaccharide binding protein (LBP and interleukin-6 (IL-6 concentrations were also determined. The observation period was a maximum of 21 days and ended with the patients’ discharge from ICU or death. Receiver operating characteristic (ROC analyses were conducted and area under the curve (AUC was calculated to determine sensitivities and specificities for the parameters. Results We found that the IG count significantly discriminates between infected and non-infected patients (P  Conclusions The total number of IG in peripheral blood from ICU patients is a good marker to discriminate infected and non-infected patients very early during SIRS. However, the IG count is not suitable as a prognostic marker for mortality. Routine and serial measurement of IGs may provide new possibilities for rapid screening of SIRS patients on ICU with suspected infections.

  6. Microfluidic colloid filtration.

    Science.gov (United States)

    Linkhorst, John; Beckmann, Torsten; Go, Dennis; Kuehne, Alexander J C; Wessling, Matthias

    2016-01-01

    Filtration of natural and colloidal matter is an essential process in today's water treatment processes. The colloidal matter is retained with the help of micro- and nanoporous synthetic membranes. Colloids are retained in a "cake layer" - often coined fouling layer. Membrane fouling is the most substantial problem in membrane filtration: colloidal and natural matter build-up leads to an increasing resistance and thus decreasing water transport rate through the membrane. Theoretical models exist to describe macroscopically the hydrodynamic resistance of such transport and rejection phenomena; however, visualization of the various phenomena occurring during colloid retention is extremely demanding. Here we present a microfluidics based methodology to follow filter cake build up as well as transport phenomena occuring inside of the fouling layer. The microfluidic colloidal filtration methodology enables the study of complex colloidal jamming, crystallization and melting processes as well as translocation at the single particle level. PMID:26927706

  7. The Microfluidic Jukebox

    Science.gov (United States)

    Tan, Say Hwa; Maes, Florine; Semin, Benoît; Vrignon, Jérémy; Baret, Jean-Christophe

    2014-04-01

    Music is a form of art interweaving people of all walks of life. Through subtle changes in frequencies, a succession of musical notes forms a melody which is capable of mesmerizing the minds of people. With the advances in technology, we are now able to generate music electronically without relying solely on physical instruments. Here, we demonstrate a musical interpretation of droplet-based microfluidics as a form of novel electronic musical instruments. Using the interplay of electric field and hydrodynamics in microfluidic devices, well controlled frequency patterns corresponding to musical tracks are generated in real time. This high-speed modulation of droplet frequency (and therefore of droplet sizes) may also provide solutions that reconciles high-throughput droplet production and the control of individual droplet at production which is needed for many biochemical or material synthesis applications.

  8. Microfluidic colloid filtration

    Science.gov (United States)

    Linkhorst, John; Beckmann, Torsten; Go, Dennis; Kuehne, Alexander J. C.; Wessling, Matthias

    2016-03-01

    Filtration of natural and colloidal matter is an essential process in today’s water treatment processes. The colloidal matter is retained with the help of micro- and nanoporous synthetic membranes. Colloids are retained in a “cake layer” - often coined fouling layer. Membrane fouling is the most substantial problem in membrane filtration: colloidal and natural matter build-up leads to an increasing resistance and thus decreasing water transport rate through the membrane. Theoretical models exist to describe macroscopically the hydrodynamic resistance of such transport and rejection phenomena; however, visualization of the various phenomena occurring during colloid retention is extremely demanding. Here we present a microfluidics based methodology to follow filter cake build up as well as transport phenomena occuring inside of the fouling layer. The microfluidic colloidal filtration methodology enables the study of complex colloidal jamming, crystallization and melting processes as well as translocation at the single particle level.

  9. Travel-related schistosomiasis, strongyloidiasis, filariasis, and toxocariasis: the risk of infection and the diagnostic relevance of blood eosinophilia

    Directory of Open Access Journals (Sweden)

    Sonder Gerard J

    2011-04-01

    Full Text Available Abstract Background This study prospectively assessed the occurrence of clinical and subclinical schistosomiasis, strongyloidiasis, filariasis, and toxocariasis, and the screening value of eosinophilia in adult short-term travelers to helminth-endemic countries. Methods Visitors of a pre-travel health advice centre donated blood samples for serology and blood cell count before and after travel. Samples were tested for eosinophilia, and for antibodies against schistosomiasis, strongyloidiasis, filariasis, and toxocariasis. Previous infection was defined as seropositivity in pre- and post-travel samples. Recent infection was defined as a seroconversion. Symptoms of parasitic disease were recorded in a structured diary. Results Previous infection was found in 112 of 1207 subjects: schistosomiasis in 2.7%, strongyloidiasis in 2.4%, filariasis in 3.4%, and toxocariasis in 1.8%. Recent schistosomiasis was found in 0.51% of susceptible subjects at risk, strongyloidiasis in 0.25%, filariasis in 0.09%, and toxocariasis in 0.08%. The incidence rate per 1000 person-months was 6.4, 3.2, 1.1, and 1.1, respectively. Recent infections were largely contracted in Asia. The positive predictive value of eosinophilia for diagnosis was 15% for previous infection and 0% for recent infection. None of the symptoms studied had any positive predictive value. Conclusion The chance of infection with schistosomiasis, strongyloidiasis, filariasis, and toxocariasis during one short-term journey to an endemic area is low. However, previous stay leads to a cumulative risk of infection. Testing for eosinophilia appeared to be of no value in routine screening of asymptomatic travelers for the four helminthic infections. Findings need to be replicated in larger prospective studies.

  10. The suitability of some blood gas and biochemical parameters as diagnostic tools or early indicators of ascites syndrome in broiler sire lines.

    Science.gov (United States)

    Hasanpur, K; Nassiri, M R; Hosseini Salekdeh, G; Vaez Torshizi, R; Pakdel, A; Kermanshahi, H; Naghous, M

    2016-06-01

    In recent few years, there have been some attempts to find a reliable indicator trait as a selection criterion against susceptibility to ascites syndrome (AS). Blood parameters were of great interest as they could be measured in live animals without implementing an ascites-inducing challenge (AIC). In this work, the suitability of some blood parameters was evaluated for diagnosing AS-susceptible chicks in later steps of the disease in trial 1 as well as their early predictive ability in trial 2. In the first trial, one hundred 1-day-old chicks from two pure broiler lines namely S1 and S2 and, in the second trial, 226 1-day-old chicks from line S2 were subjected to AIC. Saline drinking water (1200 mg/l) and lower-than-standard ambient temperatures were the implemented AICs in trials 1 and 2 respectively. The blood parameters including pH, partial pressure of O2 (pO2 ), partial pressure of CO2 (pCO2 ), bicarbonate ion concentration (BIC), percentage of haematocrit (HCT) and saturated haemoglobin (SaO2 ) were measured twice per each bird at days 28 and 35 in trial 1 and once in trial 2 at day 21. The results of the first trial revealed that in line S2 some of the blood parameters differed significantly between the ascitic and non-ascitic groups following exposure to AIC. In this line, the incidence of AS was accompanied by a lower pO2 , SaO2 and BIC, while with higher pCO2 and HCT values. In the second trial, however, although almost all of the parameters showed meaningful differences between the ascitic and non-ascitic broilers, only mean difference of BIC parameter was statistically significant. The general conclusion of this study is that the blood parameters can somewhat have diagnostic ability in the condition in which the AIC is already present, whereas the results did not approve their usefulness as early predictors of AS. PMID:26608233

  11. Animal microsurgery using microfluidics

    OpenAIRE

    Stirman, Jeffrey N.; Harker, Bethany; Lu, Hang; Crane, Matthew M.

    2013-01-01

    Small multicellular genetic organisms form a central part of modern biological research. Using these small organisms provides significant advantages in genetic tractability, manipulation, lifespan and cost. Although the small size is generally advantageous, it can make procedures such as surgeries both time consuming and labor intensive. Over the past few years there have been dramatic improvements in microfluidic technologies that enable significant improvements in microsurgery and interroga...

  12. Microfluidic Landscapes for Evolution

    OpenAIRE

    Brian M Paegel

    2010-01-01

    Evolution at its heart is an iterative algorithm composed of three steps: selection, amplification and mutagenesis. This algorithm can be applied to complex inputs such as populations of whole organisms and viruses, or mixtures of bare nucleic acids and proteins. The output is the same: evolutionary adaptation of new and improved function subject to selection. Recent breakthroughs in microfluidic technology have introduced automation and process monitoring to in vitro evolution, and reproduci...

  13. Microfluidic conductimetric bioreactor.

    Science.gov (United States)

    Limbut, Warakorn; Loyprasert, Suchera; Thammakhet, Chongdee; Thavarungkul, Panote; Tuantranont, Adisorn; Asawatreratanakul, Punnee; Limsakul, Chusak; Wongkittisuksa, Booncharoen; Kanatharana, Proespichaya

    2007-06-15

    A microfluidic conductimetric bioreactor has been developed. Enzyme was immobilized in the microfluidic channel on poly-dimethylsiloxane (PDMS) surface via covalent binding method. The detection unit consisted of two gold electrodes and a laboratory-built conductimetric transducer to monitor the increase in the conductivity of the solution due to the change of the charges generated by the enzyme-substrate catalytic reaction. Urea-urease was used as a representative analyte-enzyme system. Under optimum conditions urea could be determined with a detection limit of 0.09 mM and linearity in the range of 0.1-10 mM (r=0.9944). The immobilized urease on the microchannel chip provided good stability (>30 days of operation time) and good repeatability with an R.S.D. lower than 2.3%. Good agreement was obtained when urea concentrations of human serum samples determined by the microfluidic flow injection conductimetric bioreactor system were compared to those obtained using the Berthelot reaction (P<0.05). After prolong use the immobilized enzyme could be removed from the PDMS microchannel chip enabling new active enzyme to be immobilized and the chip to be reused. PMID:17289366

  14. Microfluidics in radiopharmaceutical chemistry

    International Nuclear Information System (INIS)

    The increased demand for molecular imaging tracers useful in assessing and monitoring diseases has stimulated research towards more efficient and flexible radiosynthetic routes, including newer technologies. The traditional vessel-based approach suffers from limitations concerning flexibility, reagent mass needed, hardware requirements, large number of connections and valves, repetitive cleaning procedures and overall big footprint to be shielded from radiation. For these reasons, several research groups have started to investigate the application of the fast growing field of microfluidic chemistry to radiosynthetic procedures. After the first report in 2004, many scientific papers have been published and demonstrated the potential for increased process yields, reduced reagent use, improved flexibility and general ease of setup. This review will address definitions occurring in microfluidics as well as analyze the different approaches under two macro-categories: microvessel and microchannel. In this perspective, several works will be collected, involving the use of positron emitting species (11C, 18F, 64Cu) and the fewer examples of gamma emitting radionuclides (99mTc, 125/131I). New directions in microfluidic research applied to PET radiochemistry, future developments and challenges are also discussed. -- Graphical abstract: Display Omitted

  15. Silk-microfluidics for advanced biotechnological applications: A progressive review.

    Science.gov (United States)

    Konwarh, Rocktotpal; Gupta, Prerak; Mandal, Biman B

    2016-01-01

    Silk based biomaterials have not only carved a unique niche in the domain of regenerative medicine but new avenues are also being explored for lab-on-a-chip applications. It is pertinent to note that biospinning of silk represents nature's signature microfluidic-maneuver. Elucidation of non-Newtonian flow of silk in the glands of spiders and silkworms has inspired researchers to fabricate devices for continuous extrusion and concentration of silk. Microfluidic channel networks within porous silk scaffolds ensure optimal nutrient and oxygen supply apart from serving as precursors for vascularization in tissue engineering applications. On the other hand, unique topographical features and surface wettability of natural silk fibers have inspired development of a number of simple and cost-effective devices for applications like blood typing and chemical sensing. This review mirrors the recent progress and challenges in the domain of silk-microfluidics for prospective avant-garde applications in the realm of biotechnology. PMID:27165254

  16. Handheld Universal Diagnostic Sensor

    Science.gov (United States)

    Chan, Eugene

    2012-01-01

    The rHEALTH technology is designed to shrink an entire hospital testing laboratory onto a handheld device. A physician or healthcare provider performs the test by collecting a fingerstick of blood from a patient. The tiny volume of blood is inserted into the rHEALTH device. Inside the device is a microfluidic chip that contains small channels about the width of a human hair. These channels help move the blood and analyze the blood sample. The rHEALTH sensor uses proprietary reagents called nanostrips, which are nanoscale test strips that enable the clinical assays. The readout is performed by laser-induced fluorescence. Overall, the time from blood collection through analysis is less than a minute.

  17. MR-based cerebral blood volume maps as a diagnostic tool of stroke: results of a clinical pilot study

    International Nuclear Information System (INIS)

    In this study the sensitivity of proving a stroke using regional cerebral blood volume (rCBV) maps were investigated. Another aim was to evaluate the strength of the ischaemia. Seven patients were examined during the acute phase of a stroke, eight during the subacute or chronically stage. To calculate rCBV-maps of one slice low dosed Gd-DTPA was injected as a bolus. Using the relaxation-effect the obtained signal intensity-time curves were converted pixel-wise to rCBV images. For the region of the infarction rCBV ratios were calculated relative to the corresponding area in the contralateral hemisphere. Only 63% of the investigations carried out during the acute phase were utilizable. In all those cases a decrease of rCBV was found. The infarct area could only be visually recognized if the rCBV ratio was lower than 0.7. The ratios of completely and partical necrotic areas of the infarctions were 0.481 and 1.028 respectively. With a p=0.0015 these values are even statistically different. During the acute stage the sensitivity of the rCBV measurement was not as high as that of morphological MR imaging. However, rCBV maps make it possible to estimate the strength of the ischaemia even during the first hours. (orig./MG)

  18. Magnetic microfluidic platform for biomedical applications using magnetic nanoparticles

    KAUST Repository

    Stipsitz, Martin

    2015-05-01

    Microfluidic platforms are well-suited for biomedical analysis and usually consist of a set of units which guarantee the manipulation, detection and recognition of bioanalyte in a reliable and flexible manner. Additionally, the use of magnetic fields for perfoming the aforementioned tasks has been steadily gainining interest. This is due to the fact that magnetic fields can be well tuned and applied either externally or from a directly integrated solution in the diagnostic system. In combination with these applied magnetic fields, magnetic nanoparticles are used. In this paper, we present some of our most recent results in research towards a) microfluidic diagnostics using MR sensors and magnetic particles and b) single cell analysis using magnetic particles. We have successfully manipulated magnetically labeled bacteria and measured their response with integrated GMR sensors and we have also managed to separate magnetically labeled jurkat cells for single cell analysis. © 2015 Trans Tech Publications, Switzerland.

  19. Acoustofluidics 1: Governing equations in microfluidics

    DEFF Research Database (Denmark)

    Bruus, Henrik

    2011-01-01

    Governing equations for microfluidics and basic flow solutions are presented. Equivalent circuit modeling for determining flow rates in microfluidic networks is introduced.......Governing equations for microfluidics and basic flow solutions are presented. Equivalent circuit modeling for determining flow rates in microfluidic networks is introduced....

  20. Microfluidic Technology in Vascular Research

    Directory of Open Access Journals (Sweden)

    A. D. van der Meer

    2009-01-01

    Full Text Available Vascular cell biology is an area of research with great biomedical relevance. Vascular dysfunction is involved in major diseases such as atherosclerosis, diabetes, and cancer. However, when studying vascular cell biology in the laboratory, it is difficult to mimic the dynamic, three-dimensional microenvironment that is found in vivo. Microfluidic technology offers unique possibilities to overcome this difficulty. In this review, an overview of the recent applications of microfluidic technology in the field of vascular biological research will be given. Examples of how microfluidics can be used to generate shear stresses, growth factor gradients, cocultures, and migration assays will be provided. The use of microfluidic devices in studying three-dimensional models of vascular tissue will be discussed. It is concluded that microfluidic technology offers great possibilities to systematically study vascular cell biology with setups that more closely mimic the in vivo situation than those that are generated with conventional methods.

  1. Laboratory diagnosis of malaria by conventional peripheral blood smear examination with Quantitative Buffy Coat (QBC and Rapid Diagnostic Tests (RDT - A comparative study

    Directory of Open Access Journals (Sweden)

    Bhat Sandhya K

    2012-10-01

    Full Text Available Aim: Rapid diagnosis is prerequisite for effective treatment and reducing mortality and morbidity of malaria. Microscopy has been the Gold standard for malaria diagnosis for decades. Recently, many new rapid diagnostic tests like Quantitative Buffy Coat (QBC examination and rapid antigen detection methods are being widely used. We made an attempt to compare peripheral smear, QBC and rapid antigen detection methods for the diagnosis of malaria. Materials and Methods: A total number of 500 samples were collected from patients presenting with classical symptoms of malaria. Thick and thin blood smears were prepared and stained with Leishman’s stain. QBC, Histidine Rich Protein-II antigen test and plasmodium Lactate Dehydrogenase tests were done using commercially available kits. Results: Taking thick smear as gold standard, thin smear had sensitivity, specificity, positive and negative predictive values of 90.9%, 100%, 100% and 98.6% respectively. QBC showed sensitivity, specificity, positive and negative predictive values of 95.45%, 100%, 100% and 99.31% respectively. HRP-II antigen detection showed sensitivity, specificity, positive and negative predictive values of 56.06%, 100%, 100% and 94.20%. pLDH showed sensitivity, specificity, PPV and NPV of 95.45%, 100%, 100% and 99.40% respectively. Conclusion: In our study, QBC had highest sensitivity followed by pLDH assay. Leishman’s stained thick smear is cost effective but requires technical expertise to interpret the results, so if facilities are available, QBC can be used for routine diagnosis. In places where facilities are not available rapid diagnostic test devices can be used, especially in endemic areas.

  2. MICROFLUIDIC COMPONENT CAPABLE OF SELF-SEALING

    DEFF Research Database (Denmark)

    2009-01-01

    A microfluidic component (100) for building a microfluidic system is provided. The microfluidic component (100) can be mounted on a microf luidic breadboard (202) in a manner that allows it to be connected to other microfluidic components (204, 206) without the requirement of additional devices....... The microfluidic component (100) comprises at least one flexible tube piece (102) for transporting a fluid. The microfluidic component (100) also comprises means for applying and maintaining pressure (104) between the flexible tube piece (102) and a tube piece (208, 210) housed in another microfluidic...

  3. MULTILEVEL (3D) MICROFLUIDIC TECHNOLOGY FOR AN INNOVATIVE MAGNETIC CELL SEPARATION PLATFORM

    OpenAIRE

    Fouet, Marc; Cargou, Sébastien; Courson, Rémi; Blatché, Charline; Montrose, A.; Reybier, K; Gué, Anne-Marie

    2014-01-01

    We demonstrate a new concept of devices, which by combining 3D fluid engineering and localized mag-netic actuation enables the full integration of a cell tagging and magnetic separation device. We used a low cost, commercially available dry film (EMS Inc, Ohio, USA) that fits microfluidic requirements and gives the possibility to build easily 3D microfluidic structures. The labelling of blood monocytes with su-perparamagnetic particles was performed "up stream" with the aim of a microparticle...

  4. Cardiovascular magnetic resonance of myocardial edema using a short inversion time inversion recovery (STIR black-blood technique: Diagnostic accuracy of visual and semi-quantitative assessment

    Directory of Open Access Journals (Sweden)

    h-Ici Darach O

    2012-03-01

    Full Text Available Abstract Background The short inversion time inversion recovery (STIR black-blood technique has been used to visualize myocardial edema, and thus to differentiate acute from chronic myocardial lesions. However, some cardiovascular magnetic resonance (CMR groups have reported variable image quality, and hence the diagnostic value of STIR in routine clinical practice has been put into question. The aim of our study was to analyze image quality and diagnostic performance of STIR using a set of pulse sequence parameters dedicated to edema detection, and to discuss possible factors that influence image quality. We hypothesized that STIR imaging is an accurate and robust way of detecting myocardial edema in non-selected patients with acute myocardial infarction. Methods Forty-six consecutive patients with acute myocardial infarction underwent CMR (day 4.5, +/- 1.6 including STIR for the assessment of myocardial edema and late gadolinium enhancement (LGE for quantification of myocardial necrosis. Thirty of these patients underwent a follow-up CMR at approximately six months (195 +/- 39 days. Both STIR and LGE images were evaluated separately on a segmental basis for image quality as well as for presence and extent of myocardial hyper-intensity, with both visual and semi-quantitative (threshold-based analysis. LGE was used as a reference standard for localization and extent of myocardial necrosis (acute or scar (chronic. Results Image quality of STIR images was rated as diagnostic in 99.5% of cases. At the acute stage, the sensitivity and specificity of STIR to detect infarcted segments on visual assessment was 95% and 78% respectively, and on semi-quantitative assessment was 99% and 83%, respectively. STIR differentiated acutely from chronically infarcted segments with a sensitivity of 95% by both methods and with a specificity of 99% by visual assessment and 97% by semi-quantitative assessment. The extent of hyper-intense areas on acute STIR images

  5. Bridging Flows: Microfluidic End‐User Solutions

    OpenAIRE

    Sabourin, David; Dufva, Martin; Snakenborg, Detlef

    2010-01-01

    Microfluidic applications hold promise for many different end‐users both within and outside, and across many different research communities. Despite the benefits of microfluidic approaches, adoption and implementation thereof is often hindered by practical issues. Microfluidic components which are more reliable and robust, and which address practical issues are required to encourage and allow non‐expert users, those not familiar with microfluidic fabrication methods, to adopt microfluidic app...

  6. Microfluidic Scintillation Detectors

    CERN Multimedia

    Microfluidic scintillation detectors are devices of recent introduction for the detection of high energy particles, developed within the EP-DT group at CERN. Most of the interest for such technology comes from the use of liquid scintillators, which entails the possibility of changing the active material in the detector, leading to an increased radiation resistance. This feature, together with the high spatial resolution and low thickness deriving from the microfabrication techniques used to manufacture such devices, is desirable not only in instrumentation for high energy physics experiments but also in medical detectors such as beam monitors for hadron therapy.

  7. Microfluidic Cell Culture Device

    Science.gov (United States)

    Takayama, Shuichi (Inventor); Cabrera, Lourdes Marcella (Inventor); Heo, Yun Seok (Inventor); Smith, Gary Daniel (Inventor)

    2014-01-01

    Microfluidic devices for cell culturing and methods for using the same are disclosed. One device includes a substrate and membrane. The substrate includes a reservoir in fluid communication with a passage. A bio-compatible fluid may be added to the reservoir and passage. The reservoir is configured to receive and retain at least a portion of a cell mass. The membrane acts as a barrier to evaporation of the bio-compatible fluid from the passage. A cover fluid may be added to cover the bio-compatible fluid to prevent evaporation of the bio-compatible fluid.

  8. Spatial manipulation with microfluidics

    Directory of Open Access Journals (Sweden)

    Benjamin eLin

    2015-04-01

    Full Text Available Biochemical gradients convey information through space, time, and concentration, and are ultimately capable of spatially resolving distinct cellular phenotypes, such as differentiation, proliferation, and migration. How these gradients develop, evolve, and function during development, homeostasis, and various disease states is a subject of intense interest across a variety of disciplines. Microfluidic technologies have become essential tools for investigating gradient sensing in vitro due to their ability to precisely manipulate fluids on demand in well controlled environments at cellular length scales. This minireview will highlight their utility for studying gradient sensing along with relevant applications to biology.

  9. Characterizing asthma from a drop of blood using neutrophil chemotaxis.

    Science.gov (United States)

    Sackmann, Eric Karl-Heinz; Berthier, Erwin; Schwantes, Elizabeth A; Fichtinger, Paul S; Evans, Michael D; Dziadzio, Laura L; Huttenlocher, Anna; Mathur, Sameer K; Beebe, David J

    2014-04-22

    Asthma is a chronic inflammatory disorder that affects more than 300 million people worldwide. Asthma management would benefit from additional tools that establish biomarkers to identify phenotypes of asthma. We present a microfluidic solution that discriminates asthma from allergic rhinitis based on a patient's neutrophil chemotactic function. The handheld diagnostic device sorts neutrophils from whole blood within 5 min, and generates a gradient of chemoattractant in the microchannels by placing a lid with chemoattractant onto the base of the device. This technology was used in a clinical setting to assay 34 asthmatic (n = 23) and nonasthmatic, allergic rhinitis (n = 11) patients to establish domains for asthma diagnosis based on neutrophil chemotaxis. We determined that neutrophils from asthmatic patients migrate significantly more slowly toward the chemoattractant compared with nonasthmatic patients (P = 0.002). Analysis of the receiver operator characteristics of the patient data revealed that using a chemotaxis velocity of 1.55 μm/min for asthma yields a diagnostic sensitivity and specificity of 96% and 73%, respectively. This study identifies neutrophil chemotaxis velocity as a potential biomarker for asthma, and we demonstrate a microfluidic technology that was used in a clinical setting to perform these measurements. PMID:24711384

  10. Measurements of diagnostic examination performance and correlation analysis using microvascular leakage, cerebral blood volume, and blood flow derived from 3T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in glial tumor grading

    International Nuclear Information System (INIS)

    To assess the diagnostic accuracy of microvascular leakage (MVL), cerebral blood volume (CBV) and blood flow (CBF) values derived from dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MR imaging) for grading of cerebral glial tumors, and to estimate the correlation between vascular permeability/perfusion parameters and tumor grades. A prospective study of 79 patients with cerebral glial tumors underwent DSC-MR imaging. Normalized relative CBV (rCBV) and relative CBF (rCBF) from tumoral (rCBVt and rCBFt), peri-enhancing region (rCBVe and rCBFe), and the value in the tumor divided by the value in the peri-enhancing region (rCBVt/e and rCBFt/e), as well as MVL, expressed as the leakage coefficient K2 were calculated. Hemodynamic variables and tumor grades were analyzed statistically and with Pearson correlations. Receiver operating characteristic (ROC) curve analyses were also performed for each of the variables. The differences in rCBVt and the maximum MVL (MVLmax) values were statistically significant among all tumor grades. Correlation analysis using Pearson was as follows: rCBVt and tumor grade, r = 0.774; rCBFt and tumor grade, r = 0.417; MVLmax and tumor grade, r = 0.559; MVLmax and rCBVt, r = 0.440; MVLmax and rCBFt, r = 0.192; and rCBVt and rCBFt, r = 0.605. According to ROC analyses for distinguishing tumor grade, rCBVt showed the largest areas under ROC curve (AUC), except for grade III from IV. Both rCBVt and MVLmax showed good discriminative power in distinguishing all tumor grades. rCBVt correlated strongly with tumor grade; the correlation between MVLmax and tumor grade was moderate. (orig.)

  11. LINE1 methylation levels associated with increased bladder cancer risk in pre-diagnostic blood DNA among US (PLCO) and European (ATBC) cohort study participants.

    Science.gov (United States)

    Andreotti, Gabriella; Karami, Sara; Pfeiffer, Ruth M; Hurwitz, Lauren; Liao, Linda M; Weinstein, Stephanie J; Albanes, Demetrius; Virtamo, Jarmo; Silverman, Debra T; Rothman, Nathaniel; Moore, Lee E

    2014-03-01

    Global methylation in blood DNA has been associated with bladder cancer risk in case-control studies, but has not been examined prospectively. We examined the association between LINE1 total percent 5-methylcytosine and bladder cancer risk using pre-diagnostic blood DNA from the United States-based, Prostate, Lung, Colorectal, Ovarian Cancer Screening Trial (PLCO) (299 cases/676 controls), and the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) cohort of Finnish male smokers (391 cases/778 controls). Logistic regression adjusted for age at blood draw, study center, pack-years of smoking, and sex was used to estimate odd ratios (ORs) and 95% confidence intervals (CIs) using study- and sex-specific methylation quartiles. In PLCO, higher, although non-significant, bladder cancer risks were observed for participants in the highest three quartiles (Q2-Q4) compared with the lowest quartile (Q1) (OR = 1.36, 95% CI: 0.96 -1.92). The association was stronger in males (Q2-Q4 vs. Q1 OR = 1.48, 95% CI: 1.00-2.20) and statistically significant among male smokers (Q2-Q4 vs. Q1 OR = 1.83, 95% CI: 1.14-2.95). No association was found among females or female smokers. Findings for male smokers were validated in ATBC (Q2-Q4 vs. Q1: OR = 2.31, 95% CI: 1.62-3.30) and a highly significant trend was observed (P = 8.7 × 10(-7)). After determining that study data could be combined, pooled analysis of PLCO and ATBC male smokers (580 cases/1119 controls), ORs were significantly higher in Q2-Q4 compared with Q1 (OR = 2.03, 95% CI: 1.52-2.72), and a trend across quartiles was observed (P = 0.0001). These findings suggest that higher global methylation levels prior to diagnosis may increase bladder cancer risk, particularly among male smokers. PMID:24316677

  12. Exploration of microfluidic devices based on multi-filament threads and textiles: A review.

    Science.gov (United States)

    Nilghaz, A; Ballerini, D R; Shen, W

    2013-01-01

    In this paper, we review the recent progress in the development of low-cost microfluidic devices based on multifilament threads and textiles for semi-quantitative diagnostic and environmental assays. Hydrophilic multifilament threads are capable of transporting aqueous and non-aqueous fluids via capillary action and possess desirable properties for building fluid transport pathways in microfluidic devices. Thread can be sewn onto various support materials to form fluid transport channels without the need for the patterned hydrophobic barriers essential for paper-based microfluidic devices. Thread can also be used to manufacture fabrics which can be patterned to achieve suitable hydrophilic-hydrophobic contrast, creating hydrophilic channels which allow the control of fluids flow. Furthermore, well established textile patterning methods and combination of hydrophilic and hydrophobic threads can be applied to fabricate low-cost microfluidic devices that meet the low-cost and low-volume requirements. In this paper, we review the current limitations and shortcomings of multifilament thread and textile-based microfluidics, and the research efforts to date on the development of fluid flow control concepts and fabrication methods. We also present a summary of different methods for modelling the fluid capillary flow in microfluidic thread and textile-based systems. Finally, we summarized the published works of thread surface treatment methods and the potential of combining multifilament thread with other materials to construct devices with greater functionality. We believe these will be important research focuses of thread- and textile-based microfluidics in future. PMID:24086179

  13. Microfluidic fuel cells and batteries

    CERN Document Server

    Kjeang, Erik

    2014-01-01

    Microfluidic fuel cells and batteries represent a special type of electrochemical power generators that can be miniaturized and integrated in a microfluidic chip. Summarizing the initial ten years of research and development in this emerging field, this SpringerBrief is the first book dedicated to microfluidic fuel cell and battery technology for electrochemical energy conversion and storage. Written at a critical juncture, where strategically applied research is urgently required to seize impending technology opportunities for commercial, analytical, and educational utility, the intention is

  14. Multiplexed electrochemical protein detection and translation to personalized cancer diagnostics.

    Science.gov (United States)

    Rusling, James F

    2013-06-01

    Measuring diagnostic panels of multiple proteins promises a new, personalized approach to early detection and therapy of diseases like cancer. Levels of biomarker proteins in patient serum can provide a continually updated record of disease status. Research in electrochemical detection of proteins has produced exquisitely sensitive approaches. Most utilize ELISA-like sandwich immunoassays incorporating various aspects of nanotechnology. Several of these ultrasensitive methodologies have been extended to microfluidic multiplexed protein detection, but engineered solutions are needed to measure more proteins in a single device from a small patient sample such as a drop of blood or tissue lysate. To achieve clinical or point-of-care (POC) use, simplicity and low cost are essential. In multiplexed microfluidic immunoassays, required reagent additions and washing steps pose a significant problem calling for creative engineering. A grand challenge is to develop a general cancer screening device to accurately measure 50-100 proteins in a simple, cost-effective fashion. This will require creative solutions to simplified reagent addition and multiplexing. PMID:23635325

  15. Security Assessment of Cyberphysical Digital Microfluidic Biochips.

    Science.gov (United States)

    Ali, Sk Subidh; Ibrahim, Mohamed; Sinanoglu, Ozgur; Chakrabarty, Krishnendu; Karri, Ramesh

    2016-01-01

    A digital microfluidic biochip (DMFB) is an emerging technology that enables miniaturized analysis systems for point-of-care clinical diagnostics, DNA sequencing, and environmental monitoring. A DMFB reduces the rate of sample and reagent consumption, and automates the analysis of assays. In this paper, we provide the first assessment of the security vulnerabilities of DMFBs. We identify result-manipulation attacks on a DMFB that maliciously alter the assay outcomes. Two practical result-manipulation attacks are shown on a DMFB platform performing enzymatic glucose assay on serum. In the first attack, the attacker adjusts the concentration of the glucose sample and thereby modifies the final result. In the second attack, the attacker tampers with the calibration curve of the assay operation. We then identify denial-of-service attacks, where the attacker can disrupt the assay operation by tampering either with the droplet-routing algorithm or with the actuation sequence. We demonstrate these attacks using a digital microfluidic synthesis simulator. The results show that the attacks are easy to implement and hard to detect. Therefore, this work highlights the need for effective protections against malicious modifications in DMFBs. PMID:26701892

  16. Patent protection and licensing in microfluidics.

    Science.gov (United States)

    Yetisen, Ali K; Volpatti, Lisa R

    2014-07-01

    Microfluidic devices offer control over low-volume samples in order to achieve high-throughput analysis, and reduce turnaround time and costs. Their efficient commercialisation has implications for biomedical sciences, veterinary medicine, environmental monitoring and industrial applications. In particular, market diffusion of microfluidic laboratory and point-of-care diagnostic devices can contribute to the improvement of global health. In their commercialisation, consultancy and patent protection are essential elements that complement academic publishing. The awareness of knowledge transfer strategies can help academics to create value for their research. The aim of this article is to provide a guidance to (1) overview the terminology in patent law, (2) elucidate the process of filing a patent in the US, EU, Japan and internationally, (3) discuss strategies to licence a patent, and (4) explain tactics to defend a patent in a potential infringement. Awareness of the patent law and rights allows obtaining optimised, valid and valuable patents, while accelerating implementation to market route. Striking a balance between academic publishing, consultancy to industry and patent protection can increase commercial potential, enhance economic growth and create social impact. PMID:24825780

  17. Simulation of magnetic active polymers for versatile microfluidic devices

    CERN Document Server

    Gusenbauer, Markus; Fischbacher, Johann; Reichel, Franz; Exl, Lukas; Bance, Simon; Kataeva, Nadezhda; Binder, Claudia; Brückl, Hubert; Schrefl, Thomas

    2013-01-01

    We propose to use a compound of magnetic nanoparticles (20-100 nm) embedded in a flexible polymer (Polydimethylsiloxane PDMS) to filter circulating tumor cells (CTCs). The analysis of CTCs is an emerging tool for cancer biology research and clinical cancer management including the detection, diagnosis and monitoring of cancer. The combination of experiments and simulations lead to a versatile microfluidic lab-on-chip device. Simulations are essential to understand the influence of the embedded nanoparticles in the elastic PDMS when applying a magnetic gradient field. It combines finite element calculations of the polymer, magnetic simulations of the embedded nanoparticles and the fluid dynamic calculations of blood plasma and blood cells. With the use of magnetic active polymers a wide range of tunable microfluidic structures can be created. The method can help to increase the yield of needed isolated CTCs.

  18. Current developments in salivary diagnostics

    OpenAIRE

    Miller, Craig S.; Foley, Joseph D.; Bailey, Alison L.; Campell, Charles L; Humphries, Roger L; Christodoulides, Nicolaos; Floriano, Pierre N.; Simmons, Glennon; Bhagwandin, Bryon; Jacobson, James W; Redding, Spencer W.; Ebersole, Jeffrey L.; McDevitt, John T

    2010-01-01

    Salivary diagnostics is an emerging field that has progressed through several important developments in the past decade, including the publication of the human salivary proteome and the infusion of federal funds to integrate nanotechnologies and microfluidic engineering concepts into developing compact point-of-care devices for rapid analysis of this secretion. In this article, we discuss some of these developments and their relevance to the prognosis, diagnosis and management of periodontiti...

  19. Solvent resistant microfluidic DNA synthesizer.

    Science.gov (United States)

    Huang, Yanyi; Castrataro, Piero; Lee, Cheng-Chung; Quake, Stephen R

    2007-01-01

    We fabricated a microfluidic DNA synthesizer out of perfluoropolyether (PFPE), an elastomer with excellent chemical compatibility which makes it possible to perform organic chemical reactions, and synthesized 20-mer oligonucleotides on chip. PMID:17180201

  20. Microfluidic Multichannel Flow Cytometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is a "Microfluidic Multichannel Flow Cytometer." Several novel concepts are integrated to produce the final design, which is compatible with...

  1. Magnetic separation in microfluidic systems

    DEFF Research Database (Denmark)

    Smistrup, Kristian

    2007-01-01

    This Ph.D. thesis presents theory, modeling, design, fabrication, experiments and results for microfluidic magnetic separators. A model for magnetic bead movement in a microfluidic channel is presented, and the limits of the model are discussed. The effective magnetic field gradient is defined, and...... it is argued that it is a good measure, when comparing the performance of magnetic bead separators. It is described how numeric modelling is used to aid the design of microfluidic magnetic separation systems. An example of a design optimization study is given. A robust fabrication scheme has been...... separation. It is shown conceptually how such a system can be applied for parallel biochemical processing in a microfluidic system. ’Passive’ magnetic separators are presented, where on-chip soft magnetic elements are magnetized by an external magnetic field and create strong magnetic fields and gradients...

  2. Passive microfluidic array card and reader

    Energy Technology Data Exchange (ETDEWEB)

    Dugan, Lawrence Christopher (Modesto, CA); Coleman, Matthew A. (Oakland, CA)

    2011-08-09

    A microfluidic array card and reader system for analyzing a sample. The microfluidic array card includes a sample loading section for loading the sample onto the microfluidic array card, a multiplicity of array windows, and a transport section or sections for transporting the sample from the sample loading section to the array windows. The microfluidic array card reader includes a housing, a receiving section for receiving the microfluidic array card, a viewing section, and a light source that directs light to the array window of the microfluidic array card and to the viewing section.

  3. Reconfigurable microfluidic platform in ice

    OpenAIRE

    Varejka, M.

    2008-01-01

    Microfluidic devices are popular tools in the biotechnology industry where they provide smaller reagent requirements, high speed of analysis and the possibility for automation. The aim of the project is to make a flexible biocompatible microfluidic platform adapted to different specific applications, mainly analytical and separations which parameters and configuration can be changed multiple times by changing corresponding computer programme. The current project has been sup...

  4. Microfluidics - Sorting particles with light

    DEFF Research Database (Denmark)

    Glückstad, J.

    2004-01-01

    Microfluidic systems have great potential to perform complex chemical and biological processing and analysis on a single disposable chip. That goal is now a step closer with the demonstration of an efficient all-optical particle sorter.......Microfluidic systems have great potential to perform complex chemical and biological processing and analysis on a single disposable chip. That goal is now a step closer with the demonstration of an efficient all-optical particle sorter....

  5. Electrodes for microfluidic applications

    Science.gov (United States)

    Crocker, Robert W.; Harnett, Cindy K.; Rognlien, Judith L.

    2006-08-22

    An electrode device for high pressure applications. These electrodes, designed to withstand pressure of greater than 10,000 psi, are adapted for use in microfluidic devices that employ electrokinetic or electrophoretic flow. The electrode is composed, generally, of an outer electrically insulating tubular body having a porous ceramic frit material disposed in one end of the outer body. The pores of the porous ceramic material are filled with an ion conductive polymer resin. A conductive material situated on the upper surface of the porous ceramic frit material and, thus isolated from direct contact with the electrolyte, forms a gas diffusion electrode. A metal current collector, in contact with the gas diffusion electrode, provides connection to a voltage source.

  6. Digital Microfluidic Cell Culture.

    Science.gov (United States)

    Ng, Alphonsus H C; Li, Bingyu Betty; Chamberlain, M Dean; Wheeler, Aaron R

    2015-01-01

    Digital microfluidics (DMF) is a droplet-based liquid-handling technology that has recently become popular for cell culture and analysis. In DMF, picoliter- to microliter-sized droplets are manipulated on a planar surface using electric fields, thus enabling software-reconfigurable operations on individual droplets, such as move, merge, split, and dispense from reservoirs. Using this technique, multistep cell-based processes can be carried out using simple and compact instrumentation, making DMF an attractive platform for eventual integration into routine biology workflows. In this review, we summarize the state-of-the-art in DMF cell culture, and describe design considerations, types of DMF cell culture, and cell-based applications of DMF. PMID:26643019

  7. Extended combined 99mTc-white blood cell and bone imaging improves the diagnostic accuracy in the detection of hip replacement infections

    International Nuclear Information System (INIS)

    Although the diagnosis of hip prosthesis infection is clinically important, X-ray studies, blood chemistry and synovial fluid aspiration may be unreliable for this purpose. The aim of this study was to evaluate whether extending the time for technetium-99m labelled leucocyte imaging to 24 h post injection improves the accuracy of diagnosis of hip replacement infections. We studied 64 symptomatic patients with hip prostheses. The presence of infections was verified by intraoperative bacterial cultures, and infection was excluded either by negative operative findings or by follow-up for at least 1 year. Leucocyte imaging was done with 99mTc-hexamethylpropylene amine oxime (HMPAO)-labelled leucocytes at 2-4 h (routine images) and at 24 h (late images) after the injection of the leucocytes. In addition, bone imaging was carried out with 99mTc-hydroxydiphosphonate (HDP) at the arterial, soft tissue and metabolic phases. A standardised method was used to compare leucocyte images with bone metabolic images. In this material, there were six confirmed infections. All the bone imaging methods had a sensitivity of 100% in detecting prosthesis infections whereas the specificity varied from only 2% to 82%. Routine leucocyte imaging was less sensitive (50% vs 83%) and less specific (90% vs 100%) than late leucocyte imaging. All tests had a high negative predictive value for excluding infection (95%-100%). However, both bone (10%-38%) and routine leucocyte imaging (33%) showed a poor positive predictive value (PPV), whereas late leucocyte imaging had a PPV of 100% and a diagnostic accuracy of 98%. We conclude that late leucocyte imaging improves the specificity of diagnosis of infected hip prostheses. This type of imaging procedure should be combined with three-phase bone scintigraphy in studies of patients with painful joint replacement. (orig.)

  8. Microfluidic Plastic Devices for Single-use Applications in High-Throughput Screening and DNA-Analysis

    OpenAIRE

    Gerlach, Andreas; Knebel, Günther; Guber, A. E.; Heckele, M.; Herrmann, D.; Muslija, A.; Schaller, T.

    2001-01-01

    Microfluidic devices fabricated by mass production offer an immense potential of applications such as high-throughput drug screening, clinical diagnostics and gene analysis [1]. The low unit production costs of plastic substrates make it possible to produce single-use devices, eliminating the need for cleaning and reuse [2]. Fabrication of microfluidic devices can be applied by microtechnical fabrication processes in combination with plastic molding techniques [3]. Basically, replication...

  9. Plasma treatments of wool fiber surface for microfluidic applications

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, So-Hyoun; Hwang, Ki-Hwan; Lee, Jin Su [Department of Chemistry, Sungkyunkwan University, 440-746 Suwon (Korea, Republic of); Boo, Jin-Hyo, E-mail: jhboo@skku.edu [Department of Chemistry, Sungkyunkwan University, 440-746 Suwon (Korea, Republic of); Yun, Sang H., E-mail: shy@kth.se [Institute of Basic Science, Sungkyunkwan University, 440-746 Suwon (Korea, Republic of)

    2015-09-15

    Highlights: • We used atmospheric plasma for tuning the wettability of wool fibers. • The wicking rates of the wool fibers increased with increasing treatment time. • The increasing of wettability results in removement of fatty acid on the wool surface. - Abstract: Recent progress in health diagnostics has led to the development of simple and inexpensive systems. Thread-based microfluidic devices allow for portable and inexpensive field-based technologies enabling medical diagnostics, environmental monitoring, and food safety analysis. However, controlling the flow rate of wool thread, which is a very important part of thread-based microfluidic devices, is quite difficult. For this reason, we focused on thread-based microfluidics in the study. We developed a method of changing the wettability of hydrophobic thread, including wool thread. Thus, using natural wool thread as a channel, we demonstrate herein that the manipulation of the liquid flow, such as micro selecting and micro mixing, can be achieved by applying plasma treatment to wool thread. In addition to enabling the flow control of the treated wool channels consisting of all natural substances, this procedure will also be beneficial for biological sensing devices. We found that wools treated with various gases have different flow rates. We used an atmospheric plasma with O{sub 2}, N{sub 2} and Ar gases.

  10. Microfluidic Mixing Technology for a Universal Health Sensor

    Science.gov (United States)

    Chan, Eugene Y.; Bae, Candice

    2009-01-01

    A highly efficient means of microfluidic mixing has been created for use with the rHEALTH sensor an elliptical mixer and passive curvilinear mixing patterns. The rHEALTH sensor provides rapid, handheld, complete blood count, cell differential counts, electrolyte measurements, and other lab tests based on a reusable, flow-based microfluidic platform. These geometries allow for cleaning in a reusable manner, and also allow for complete mixing of fluid streams. The microfluidic mixing is performed by flowing two streams of fluid into an elliptical or curvilinear design that allows the combination of the flows into one channel. The mixing is accomplished by either chaotic advection around micro - fluidic loops. All components of the microfluidic chip are flow-through, meaning that cleaning solution can be introduced into the chip to flush out cells, plasma proteins, and dye. Tests were performed on multiple chip geometries to show that cleaning is efficient in any flowthrough design. The conclusion from these experiments is that the chip can indeed be flushed out with microliter volumes of solution and biological samples are cleaned readily from the chip with minimal effort. The technology can be applied in real-time health monitoring at patient s bedside or in a doctor s office, and real-time clinical intervention in acute situations. It also can be used for daily measurement of hematocrit for patients on anticoagulant drugs, or to detect acute myocardial damage outside a hospital.

  11. Isolation of cancer cells by "in situ" microfluidic biofunctionalization protocols

    KAUST Repository

    De Vitis, Stefania

    2014-07-01

    The aim of this work is the development of a microfluidic immunosensor for the immobilization of cancer cells and their separation from healthy cells by using "in situ" microfluidic biofunctionalization protocols. These protocols allow to link antibodies on microfluidic device surfaces and can be used to study the interaction between cell membrane and biomolecules. Moreover they allow to perform analysis with high processing speed, small quantity of reagents and samples, short reaction times and low production costs. In this work the developed protocols were used in microfluidic devices for the isolation of cancer cells in heterogeneous blood samples by exploiting the binding of specific antibody to an adhesion protein (EpCAM), overexpressed on the tumor cell membranes. The presented biofunctionalization protocols can be performed right before running the experiment: this allows to have a flexible platform where biomolecules of interest can be linked on the device surface according to the user\\'s needs. © 2014 Elsevier B.V. All rights reserved.

  12. Microfluidic approach of Sickled Cell Anemia

    Science.gov (United States)

    Abkarian, Manouk; Loiseau, Etienne; Massiera, Gladys

    2012-11-01

    Sickle Cell Anemia is a disorder of the microcirculation caused by a genetic point mutation that produces an altered hemoglobin protein called HbS. HbS self-assembles reversibly into long rope like fibers inside the red blood cells. The resulting distorded sickled red blood cells are believed to block the smallest capillaries of the tissues producing anemia. Despite the large amount of work that provided a thorough understanding of HbS polymerization in bulk as well as in intact red blood cells at rest, no consequent cellular scale approaches of the study of polymerization and its link to the capillary obstruction have been proposed in microflow, although the problem of obstruction is in essence a circulatory problem. Here, we use microfluidic channels, designed to mimic physiological conditions (flow velocity, oxygen concentration, hematocrit...) of the microcirculation to carry out a biomimetic study at the cellular scale of sickled cell vaso-occlusion. We show that flow geometry, oxygen concentration, white blood cells and free hemoglobin S are essential in the formation of original cell aggregates which could play a role in the vaso-occlusion events.

  13. Microfluidic tools for cell biological research

    OpenAIRE

    Velve-Casquillas, Guilhem; Le Berre, Maël; Piel, Matthieu; Tran, Phong T.

    2010-01-01

    Microfluidic technology is creating powerful tools for cell biologists to control the complete cellular microenvironment, leading to new questions and new discoveries. We review here the basic concepts and methodologies in designing microfluidic devices, and their diverse cell biological applications.

  14. Bridging Flows: Microfluidic End‐User Solutions

    DEFF Research Database (Denmark)

    Sabourin, David

    Microfluidic applications hold promise for many different end‐users both within and outside, and across many different research communities. Despite the benefits of microfluidic approaches, adoption and implementation thereof is often hindered by practical issues. Microfluidic components which are...... more reliable and robust, and which address practical issues are required to encourage and allow non‐expert users, those not familiar with microfluidic fabrication methods, to adopt microfluidic approaches. The first practical challenge encountered by users of microfluidics is the creation of...... interconnections between microfluidic devices and the outside world. This challenge results from the lack of standards for interconnecting components and the scale disparity between typical microfluidic channel dimensions, microns to hundreds of microns, and the “macro” methods required to address these channels...

  15. Rapid, low-cost prototyping of centrifugal microfluidic devices for effective implementation of various microfluidic components

    OpenAIRE

    Smith, Suzanne; Land, Kevin; Madou, Marc; Kido, Horacio

    2015-01-01

    A centrifugal microfluidic platform to develop various microfluidic operations – the first of its kind in South Africa – is presented. Rapid and low-cost prototyping of centrifugal microfluidic disc devices, as well as a set-up to test the devices using centrifugal forces, is described. Preliminary results show that various microfluidic operations such as fluidic valving, transportation, and microfluidic droplet generation can be achieved. This work provides a complete centrifugal microfluidi...

  16. Imaging label-free biosensor with microfluidic system

    Science.gov (United States)

    Jahns, S.; Glorius, P.; Hansen, M.; Nazirizadeh, Y.; Gerken, M.

    2015-06-01

    We present a microfluidic system suitable for parallel label-free detection of several biomarkers utilizing a compact imaging measurement system. The microfluidic system contains a filter unit to separate the plasma from human blood and a functionalized, photonic crystal slab sensor chip. The nanostructure of the photonic crystal slab sensor chip is fabricated by nanoimprint lithography of a period grating surface into a photoresist and subsequent deposition of a TiO2 layer. Photonic crystal slabs are slab waveguides supporting quasi-guided modes coupling to far-field radiation, which are sensitive to refractive index changes due to biomarker binding on the functionalized surface. In our imaging read-out system the resulting resonance shift of the quasi-guided mode in the transmission spectrum is converted into an intensity change detectable with a simple camera. By continuously taking photographs of the sensor surface local intensity changes are observed revealing the binding kinetics of the biomarker to its specific target. Data from two distinct measurement fields are used for evaluation. For testing the sensor chip, 1 μM biotin as well as 1 μM recombinant human CD40 ligand were immobilized in spotsvia amin coupling to the sensor surface. Each binding experiment was performed with 250 nM streptavidin and 90 nM CD40 ligand antibody dissolved in phosphate buffered saline. In the next test series, a functionalized sensor chip was bonded onto a 15 mm x 15 mm opening of the 75 mm x 25 mm x 2 mm microfluidic system. We demonstrate the functionality of the microfluidic system for filtering human blood such that only blood plasma was transported to the sensor chip. The results of first binding experiments in buffer with this test chip will be presented.

  17. Recent Progress of Microfluidics in Translational Applications.

    Science.gov (United States)

    Liu, Zongbin; Han, Xin; Qin, Lidong

    2016-04-01

    Microfluidics, featuring microfabricated structures, is a technology for manipulating fluids at the micrometer scale. The small dimension and flexibility of microfluidic systems are ideal for mimicking molecular and cellular microenvironment, and show great potential in translational research and development. Here, the recent progress of microfluidics in biological and biomedical applications, including molecular analysis, cellular analysis, and chip-based material delivery and biomimetic design is presented. The potential future developments in the translational microfluidics field are also discussed. PMID:27091777

  18. Recent Progress of Microfluidics in Translational Applications

    OpenAIRE

    Liu, Zongbin; Han, Xin; Qin, Lidong

    2016-01-01

    Microfluidics, featuring microfabricated structures, is a technology for manipulating fluids at the micrometer scale. The small dimension and flexibility of microfluidic systems are ideal for mimicking molecular and cellular microenvironment, and show great potential in translational research and development. Here, the recent progress of microfluidics in biological and biomedical applications, including molecular analysis, cellular analysis, and chip-based material delivery and biomimetic des...

  19. Colloidal core-seeded semiconductor nanorods as fluorescent labels for in-vitro diagnostics (Conference Presentation)

    Science.gov (United States)

    Chan, YinThai

    2016-03-01

    Colloidal semiconductor nanocrystals are ideal fluorophores for clinical diagnostics, therapeutics, and highly sensitive biochip applications due to their high photostability, size-tunable color of emission and flexible surface chemistry. The relatively recent development of core-seeded semiconductor nanorods showed that the presence of a rod-like shell can confer even more advantageous physicochemical properties than their spherical counterparts, such as large multi-photon absorption cross-sections and facet-specific chemistry that can be exploited to deposit secondary nanoparticles. It may be envisaged that these highly fluorescent nanorods can be integrated with large scale integrated (LSI) microfluidic systems that allow miniaturization and integration of multiple biochemical processes in a single device at the nanoliter scale, resulting in a highly sensitive and automated detection platform. In this talk, I will describe a LSI microfluidic device that integrates RNA extraction, reverse transcription to cDNA, amplification and target pull-down to detect histidine decarboxylase (HDC) gene directly from human white blood cells samples. When anisotropic colloidal semiconductor nanorods (NRs) were used as the fluorescent readout, the detection limit was found to be 0.4 ng of total RNA, which was much lower than that obtained using spherical quantum dots (QDs) or organic dyes. This was attributed to the large action cross-section of NRs and their high probability of target capture in a pull-down detection scheme. The combination of large scale integrated microfluidics with highly fluorescent semiconductor NRs may find widespread utility in point-of-care devices and multi-target diagnostics.

  20. Microfluidic reflow pumps.

    Science.gov (United States)

    Haslam, Bryan; Tsai, Long-Fang; Anderson, Ryan R; Kim, Seunghyun; Hu, Weisheng; Nordin, Gregory P

    2015-07-01

    A new microfluidic pump, termed a reflow pump, is designed to operate with a sub-μl sample volume and transport it back and forth between two pneumatically actuated reservoirs through a flow channel typically containing one or more sensor surfaces. The ultimate motivation is to efficiently use the small sample volume in conjunction with convection to maximize analyte flux to the sensor surface(s) in order to minimize sensor response time. In this paper, we focus on the operational properties of the pumps themselves (rather than the sensor surfaces), and demonstrate both two-layer and three-layer polydimethylsiloxane reflow pumps. For the three-layer pump, we examine the effects of reservoir actuation pressure and actuation period, and demonstrate average volumetric flow rates as high as 500 μl/min. We also show that the two-layer design can pump up to 93% of the sample volume during each half period and demonstrate integration of a reflow pump with a single-chip microcantilever array to measure maximum flow rate. PMID:26221199

  1. Microfluidic sorting of microtissues.

    Science.gov (United States)

    Buschke, D G; Resto, P; Schumacher, N; Cox, B; Tallavajhula, A; Vivekanandan, A; Eliceiri, K W; Williams, J C; Ogle, B M

    2012-03-01

    Increasingly, invitro culture of adherent cell types utilizes three-dimensional (3D) scaffolds or aggregate culture strategies to mimic tissue-like, microenvironmental conditions. In parallel, new flow cytometry-based technologies are emerging to accurately analyze the composition and function of these microtissues (i.e., large particles) in a non-invasive and high-throughput way. Lacking, however, is an accessible platform that can be used to effectively sort or purify large particles based on analysis parameters. Here we describe a microfluidic-based, electromechanical approach to sort large particles. Specifically, sheath-less asymmetric curving channels were employed to separate and hydrodynamically focus particles to be analyzed and subsequently sorted. This design was developed and characterized based on wall shear stress, tortuosity of the flow path, vorticity of the fluid in the channel, sorting efficiency and enrichment ratio. The large particle sorting device was capable of purifying fluorescently labelled embryoid bodies (EBs) from unlabelled EBs with an efficiency of 87.3% ± 13.5%, and enrichment ratio of 12.2 ± 8.4 (n = 8), while preserving cell viability, differentiation potential, and long-term function. PMID:22505992

  2. Microfluidic Technologies for Synthetic Biology

    Directory of Open Access Journals (Sweden)

    Sung Kuk Lee

    2011-06-01

    Full Text Available Microfluidic technologies have shown powerful abilities for reducing cost, time, and labor, and at the same time, for increasing accuracy, throughput, and performance in the analysis of biological and biochemical samples compared with the conventional, macroscale instruments. Synthetic biology is an emerging field of biology and has drawn much attraction due to its potential to create novel, functional biological parts and systems for special purposes. Since it is believed that the development of synthetic biology can be accelerated through the use of microfluidic technology, in this review work we focus our discussion on the latest microfluidic technologies that can provide unprecedented means in synthetic biology for dynamic profiling of gene expression/regulation with high resolution, highly sensitive on-chip and off-chip detection of metabolites, and whole-cell analysis.

  3. An Anti-Adhesion Technique in Microfluidic Channel Using Dielectrophoresis for Particle Processing Microfluidic Chip Applications.

    Science.gov (United States)

    Kang, Dong-Hyun; Kim, Min-Gu; Seo, Hye-Kyoung; Kim, Yong-Jun

    2015-09-01

    Particle adhesion to the walls of microfluidic channels is a prominent cause of deteriorating performance and reliability in miniaturized analytical devices; it can also cause unexpected changes in their structures and operating conditions. Therefore, the demand of anti-adhesion for wall loss reduction on particle processing chips is high. This paper demonstrates an anti-adhesion technique using dielectrophoresis. The proposed technique is applied to a distribution microchannel for a feasibility test and is then applied to a blood plasma filter, which is a human blood cell and plasma separation device. In the distribution microchannel, the application of electric potentials of 0-20 V(pp) at 3 MHz caused the wall loss of polystyrene latex (PSL) particles to decrease with decreasing particle diameter. When an electric potential of 20 V(pp) was applied in a distribution microchannel experiment using PSL particles, the wall loss decreased by 52.7 ± 3% for 10-μm-diameter particles. On the other hand, when a 20 V(pp) electric potential was applied in a distribution microchannel experiment using human blood cells, the wall loss decreased by 66.4 ± 6%. In the blood plasma filter, the wall loss decreased by 54.89 ± 5% at 20 V(pp) and 1 MHz. The purity efficiency of the blood plasma filter was 69.56% without the wall loss reduction technique and 95.14% when the applied electric potential was 20 V(pp). PMID:26485924

  4. How to integrate a micropipette into a closed microfluidic system: absorption spectra of an optically trapped erythrocyte

    OpenAIRE

    Alrifaiy, Ahmed; Ramser, Kerstin

    2011-01-01

    We present a new concept of integrating a micropipette within a closed microfluidic system equipped with optical tweezers and a UV-Vis spectrometer. A single red blood cell (RBC) was optically trapped and steered in three dimensions towards a micropipette that was integrated in the microfluidic system. Different oxygenation states of the RBC, triggered by altering the oxygen content in the microchannels through a pump system, were optically monitored by a UV-Vis spectrometer. The built setup ...

  5. Microfluidic device for drug delivery

    Science.gov (United States)

    Beebe, David J. (Inventor); MacDonald, Michael J. (Inventor); Eddington, David T. (Inventor); Mensing, Glennys A. (Inventor)

    2010-01-01

    A microfluidic device is provided for delivering a drug to an individual. The microfluidic device includes a body that defines a reservoir for receiving the drug therein. A valve interconnects the reservoir to an output needle that is insertable into the skin of an individual. A pressure source urges the drug from the reservoir toward the needle. The valve is movable between a closed position preventing the flow of the drug from the reservoir to the output needle and an open position allowing for the flow of the drug from the reservoir to the output needle in response to a predetermined condition in the physiological fluids of the individual.

  6. Osteocyte culture in microfluidic devices

    OpenAIRE

    Wei, Chao; Fan, Beiyuan; Chen, Deyong; Liu, Chao; Wei, Yuanchen; Huo, Bo; You, Lidan; Wang, Junbo; Chen, Jian

    2015-01-01

    This paper presents a microfluidic device (poly-dimethylsiloxane micro channels bonded with glass slides) enabling culture of MLO-Y4 osteocyte like cells. In this study, on-chip collagen coating, cell seeding and culture, as well as staining were demonstrated in a tubing-free manner where gravity was used as the driving force for liquid transportation. MLO-Y4 cells were cultured in microfluidic channels with and without collagen coating where cellular images in a time sequence were taken and ...

  7. Microfluidics for single cell analysis

    DEFF Research Database (Denmark)

    Jensen, Marie Pødenphant

    cells, and simultaneously be fabricated and operated at low costs and be user-friendly. These challenges were addressed through development of two microfluidic devices, one for rare cell isolation based on pinched flow fractionation (PFF) and one for single cell capture based on hydrodynamic trapping....... Both devices were fabricated by injection moulding with a nickel master. CTC isolation was realised using PFF, which is a passive, size-based microfluidic technique. The focus was mainly on experimental work; however designs were based on flow calculations and analysed with numerical simulations to...

  8. Integrated microfluidic systems for DNA analysis.

    Science.gov (United States)

    Njoroge, Samuel K; Chen, Hui-Wen; Witek, Małgorzata A; Soper, Steven A

    2011-01-01

    The potential utility of genome-related research in terms of evolving basic discoveries in biology has generated widespread use of DNA diagnostics and DNA forensics and driven the accelerated development of fully integrated microfluidic systems for genome processing. To produce a microsystem with favorable performance characteristics for genetic-based analyses, several key operational elements must be strategically chosen, including device substrate material, temperature control, fluidic control, and reaction product readout. As a matter of definition, a microdevice is a chip that performs a single processing step, for example microchip electrophoresis. Several microdevices can be integrated to a single wafer, or combined on a control board as separate devices to form a microsystem. A microsystem is defined as a chip composed of at least two microdevices. Among the many documented analytical microdevices, those focused on the ability to perform the polymerase chain reaction (PCR) have been reported extensively due to the importance of this processing step in most genetic-based assays. Other microdevices that have been detailed in the literature include those for solid-phase extractions, microchip electrophoresis, and devices composed of DNA microarrays used for interrogating DNA primary structure. Great progress has also been made in the areas of chip fabrication, bonding and sealing to enclose fluidic networks, evaluation of different chip substrate materials, surface chemistries, and the architecture of reaction conduits for basic processing steps such as mixing. Other important elements that have been developed to realize functional systems include miniaturized readout formats comprising optical or electrochemical transduction and interconnect technologies. These discoveries have led to the development of fully autonomous and functional integrated systems for genome processing that can supply "sample in/answer out" capabilities. In this chapter, we focus on

  9. Characterization of a microfluidic microbial fuel cell as a power generator based on a nickel electrode.

    Science.gov (United States)

    Mardanpour, Mohammad Mahdi; Yaghmaei, Soheila

    2016-05-15

    This study reports the fabrication of a microfluidic microbial fuel cell (MFC) using nickel as a novel alternative for conventional electrodes and a non-phatogenic strain of Escherichia coli as the biocatalyst. The feasibility of a microfluidic MFC as an efficient power generator for production of bioelectricity from glucose and urea as organic substrates in human blood and urine for implantable medical devices (IMDs) was investigated. A maximum open circuit potential of 459 mV was achieved for the batch-fed microfluidic MFC. During continuous mode operation, a maximum power density of 104 Wm(-3) was obtained with nutrient broth. For the glucose-fed microfluidic MFC, the maximum power density of 5.2 μW cm(-2) obtained in this study is significantly greater than the power densities reported previously for microsized MFCs and glucose fuel cells. The maximum power density of 14 Wm(-3) obtained using urea indicates the successful performance of a microfluidic MFC using human excreta. It features high power density, self-regeneration, waste management and a low production cost (<$1), which suggest it as a promising alternative to conventional power supplies for IMDs. The performance of the microfluidic MFC as a power supply was characterized based on polarization behavior and cell potential in different substrates, operational modes, and concentrations. PMID:26720922

  10. A personification heuristic Genetic Algorithm for Digital Microfluidics-based Biochips Placement

    Directory of Open Access Journals (Sweden)

    Jingsong Yang

    2013-06-01

    Full Text Available A personification heuristic Genetic Algorithm is established for the placement of digital microfluidics-based biochips, in which, the personification heuristic algorithm is used to control the packing process, while the genetic algorithm is designed to be used in multi-objective placement results optimizing. As an example, the process of microfluidic module physical placement in multiplexed in-vitro diagnostics on human physiological fluids is simulated. The experiment results show that personification heuristic genetic algorithm can achieve better results in multi-objective optimization, compare to the parallel recombinative simulated annealing algorithm.

  11. MICROFLUIDIC MODULES FOR ISOLATION OF RECOMBINANT CYTOKINE FROM BACTERIAL LYSATES

    Energy Technology Data Exchange (ETDEWEB)

    Retterer, Scott T [ORNL; Doktycz, Mitchel John [ORNL

    2014-01-01

    The portability and personalization of health-care diagnostics and treatments benefits from advancements and applications of micro and nanotechnology. Modularization and miniaturization of standardized biochemical processes and tests facilitates the advancement and customization of analyte detection and diagnosis on-chip. The goal of our work here is to develop modular platforms for on-chip biochemical processing of synthesized biologics for a range of on-demand applications. Our report focuses on the initial development, characterization and application of microfluidic size exclusion/gel filtration and ion exchange protein concentration modules for cytokine isolation from spiked cell extracts.

  12. Particle manipulation through polymer solutions in microfluidic processes

    Science.gov (United States)

    Del Giudice, F.; D'Avino, G.; Villone, M. M.; Greco, F.; Maffettone, P. L.

    2015-12-01

    Manipulation of particles suspended in fluids flowing in microfluidic channels is required in a variety of biological, diagnostic and therapeutic applications. For instance, alignment of particles into a tight stream is a necessary step prior to counting, detecting, and sorting. Generally, this task is accomplished by using a Newtonian fluid as suspending medium and by properly fabricating a complex device aimed to displace particle trajectories. In the last years, however, the use of polymeric liquids in microfluidic processes has received a growing interest. Indeed, the addition of a small amount of polymer in a Newtonian suspension flowing in a channel promotes "internal" forces that can be exploited to manipulate the trajectories of suspended particles in simple devices. In this work, we show the possibility to align particles in simple square-shaped microfluidic channels by exploiting viscoelastic forces in flowing suspending liquids. Experiments have been performed to investigate the effect of the channel length, flow rate, confinement ratio (i.e., the ratio between the particle and channel size) and fluid rheology on the particle alignment. Finally, we present experimental results where particle alignment induced by fluid viscoelasticity is combined with magnetophoresis to deflect magnetic beads in a H-shaped channel. High-efficiency separation of magnetic and non-magnetic beads is demonstrated.

  13. Fabrication of plastic microfluidic components

    Science.gov (United States)

    Martin, Peter M.; Matson, Dean W.; Bennett, Wendy D.; Hammerstrom, D. J.

    1998-09-01

    Plastic components have many advantages, including ease of fabrication, low cost, chemical inertness, lightweight, and disposability. We report on the fabrication of three plastics-based microfluidic components: a motherboard, a dialysis unit, and a metal sensor. Microchannels, headers, and interconnects were produced in thin sheets (>=50 microns) of polyimide, PMMA, polyethylene, and polycarbonate using a direct-write excimer laser micromachining system. Machined sheets were laminated by thermal and adhesive bonding to form leak-tight microfluidic components. The microfluidic motherboard borrowed the `functionality on a chip' concept from the electronics industry and was the heart of a complex microfluidic analytical device. The motherboard platform was designed to be tightly integrated and self-contained (i.e., liquid flows are all confined within machined microchannels), reducing the need for tubing with fluid distribution and connectivity. This concept greatly facilitated system integration and miniaturization. As fabricated, the motherboard consisted of three fluid reservoirs connected to micropumps by microchannels. The fluids could either be pumped independently or mixed in microchannels prior to being directed to exterior analytical components via outlet ports. The microdialysis device was intended to separate electrolytic solutes from low volume samples prior to mass spectrometric analysis. The device consisted of a dialysis membrane laminated between opposed serpentine microchannels containing the sample fluid and a buffer solution. The laminated metal sensor consisted of fluid reservoirs, micro-flow channels, micropumps, mixing channels, reaction channels, and detector circuitry.

  14. Osteocyte culture in microfluidic devices.

    Science.gov (United States)

    Wei, Chao; Fan, Beiyuan; Chen, Deyong; Liu, Chao; Wei, Yuanchen; Huo, Bo; You, Lidan; Wang, Junbo; Chen, Jian

    2015-01-01

    This paper presents a microfluidic device (poly-dimethylsiloxane micro channels bonded with glass slides) enabling culture of MLO-Y4 osteocyte like cells. In this study, on-chip collagen coating, cell seeding and culture, as well as staining were demonstrated in a tubing-free manner where gravity was used as the driving force for liquid transportation. MLO-Y4 cells were cultured in microfluidic channels with and without collagen coating where cellular images in a time sequence were taken and analyzed, confirming the positive effect of collagen coating on phenotype maintaining of MLO-Y4 cells. The proliferating cell nuclear antigen based proliferation assay was used to study cellular proliferation, revealing a higher proliferation rate of MLO-Y4 cells seeded in microfluidic channels without collagen coating compared to the substrates coated with collagen. Furthermore, the effects of channel dimensions (variations in width and height) on the viability of MLO-Y4 cells were explored based on the Calcein-AM and propidium iodide based live/dead assay and the Hoechst 33258 based apoptosis assay, locating the correlation between the decrease in channel width or height and the decrease in cell viability. As a platform technology, this microfluidic device may function as a new cell culture model enabling studies of osteocytes. PMID:25713691

  15. Mixing in a Microfluid Device

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Deryabin, Mikhail

    Mixing of fluids in microchannels cannot rely on turbulence since the flow takes place at extremly low Reynolds numbers. Various active and passive devices have been developed to induce mixing in microfluid flow devices. We describe here a model of an active mixer where a transverse periodic flow...

  16. Topology optimization of microfluidic mixers

    DEFF Research Database (Denmark)

    Andreasen, Casper Schousboe; Gersborg, Allan Roulund; Sigmund, Ole

    2009-01-01

    This paper demonstrates the application of the topology optimization method as a general and systematic approach for microfluidic mixer design. The mixing process is modeled as convection dominated transport in low Reynolds number incompressible flow. The mixer performance is maximized by altering...

  17. A microfluidic device with pillars

    DEFF Research Database (Denmark)

    2014-01-01

    The invention provides a microfluidic device for mixing liquid reagents, the device comprises, a chip forming at least one reaction chamber between a bottom and a top and extending between an inlet and an outlet. To enable manufacturing from less rigid materials, the device comprises pillars...

  18. Optical detection in microfluidic systems

    DEFF Research Database (Denmark)

    Mogensen, Klaus Bo; Kutter, Jörg Peter

    2009-01-01

    Optical detection schemes continue to be favoured for measurements in microfluidic systems. A selection of the latest progress mainly within the last two years is critically reviewed. Emphasis is on integrated solutions, such as planar waveguides, coupling schemes to the outside world, evanescent...

  19. Spintronic microfluidic platform for biomedical and environmental applications

    Science.gov (United States)

    Cardoso, F. A.; Martins, V. C.; Fonseca, L. P.; Germano, J.; Sousa, L. A.; Piedade, M. S.; Freitas, P. P.

    2010-09-01

    Faster, more sensitive and easy to operate biosensing devices still are a need at important areas such as biomedical diagnostics, food control and environmental monitoring. Recently, spintronic-devices have emerged as a promising alternative to the existent technologies [1-3]. A number of advantages, namely high sensitivity, easy integration, miniaturization, scalability, robustness and low cost make these devices potentially capable of responding to the existent technological need. In parallel, the field of microfluidics has shown great advances [4]. Microfluidic systems allow the analysis of small sample volumes (from micro- down to pico-liters), often by automate sample processing with the ability to integrate several steps into a single device (analyte amplification, concentration, separation and/or labeling), all in a reduced assay time (minutes to hours) and affordable cost. The merging of these two technologies, magnetoresistive biochips and microfluidics, will enable the development of highly competitive devices. This work reports the integration of a magnetoresistive biochip with a microfluidic system inside a portable and autonomous electronic platform aiming for a fully integrated device. A microfluidic structure fabricated in polydimethylsiloxane with dimensions of W: 0.5mm, H: 0.1mm, L: 10mm, associated to a mechanical system to align and seal the channel by pressure is presented (Fig. 1) [5]. The goal is to perform sample loading and transportation over the chip and simultaneously control the stringency and uniformity of the wash-out process. The biochip output is acquired by an electronic microsystem incorporating the circuitry to control, address and read-out the 30 spin-valve sensors sequentially (Fig. 1) [2]. This platform is being applied to the detection of water-borne microbial pathogens (e.g. Salmonella and Escherichia coli) and genetic diseases diagnosis (e.g. cystic fibrosis) through DNA hybridization assays. Open chamber measurements were

  20. Fully Automated Quantification of Insulin Concentration Using a Microfluidic-Based Chemiluminescence Immunoassay.

    Science.gov (United States)

    Yao, Ping; Liu, Zhu; Tung, Steve; Dong, Zaili; Liu, Lianqing

    2016-06-01

    A fully automated microfluidic-based detection system for the rapid determination of insulin concentration through a chemiluminescence immunoassay has been developed. The microfluidic chip used in the system is a double-layered polydimethylsiloxane device embedded with interconnecting micropumps, microvalves, and a micromixer. At a high injection rate of the developing solution, the chemiluminescence signal can be excited and measured within a short period of time. The integral value of the chemiluminescence light signal is used to determine the insulin concentration of the samples, and the results indicate that the measurement is accurate in the range from 1.5 pM to 391 pM. The entire chemiluminescence assay can be completed in less than 10 min. The fully automated microfluidic-based insulin detection system provides a useful platform for rapid determination of insulin in clinical diagnostics for diabetes, which is expected to become increasingly important for future point-of-care applications. PMID:25824205

  1. Nanoelectromechanical Chip (NELMEC) Combination of Nanoelectronics and Microfluidics to Diagnose Epithelial and Mesenchymal Circulating Tumor Cells from Leukocytes.

    Science.gov (United States)

    Hosseini, Seied Ali; Abdolahad, Mohammad; Zanganeh, Somayeh; Dahmardeh, Mahyar; Gharooni, Milad; Abiri, Hamed; Alikhani, Alireza; Mohajerzadeh, Shams; Mashinchian, Omid

    2016-02-17

    An integrated nano-electromechanical chip (NELMEC) has been developed for the label-free distinguishing of both epithelial and mesenchymal circulating tumor cells (ECTCs and MCTCs, respectively) from white blood cells (WBCs). This nanoelectronic microfluidic chip fabricated by silicon micromachining can trap large single cells (>12 µm) at the opening of the analysis microchannel arrays. The nature of the captured cells is detected using silicon nanograss (SiNG) electrodes patterned at the entrance of the channels. There is an observable difference between the membrane capacitance of the ECTCs and MCTCs and that of WBCs (measured using SiNG electrodes), which is the key indication for our diagnosis. The NELMEC chip not only solves the problem of the size overlap between CTCs and WBCs but also detects MCTCs without the need for any markers or tagging processes, which has been an important problem in previously reported CTC detection systems. The great conductivity of the gold-coated SiNG nanocontacts as well as their safe penetration into the membrane of captured cells, facilitate a precise and direct signal extraction to distinguish the type of captured cell. The results achieved from epithelial (MCF-7) and mesenchymal (MDA-MB231) breast cancer cells circulated in unprocessed blood suggest the significant applications for these diagnostic abilities of NELMEC. PMID:26727927

  2. Ice matrix in reconfigurable microfluidic systems

    International Nuclear Information System (INIS)

    Microfluidic devices find many applications in biotechnologies. Here, we introduce a flexible and biocompatible microfluidic ice-based platform with tunable parameters and configuration of microfluidic patterns that can be changed multiple times during experiments. Freezing and melting of cavities, channels and complex relief structures created and maintained in the bulk of ice by continuous scanning of an infrared laser beam are used as a valve action in microfluidic systems. We demonstrate that pre-concentration of samples and transport of ions and dyes through the open channels created can be achieved in ice microfluidic patterns by IR laser-assisted zone melting. The proposed approach can be useful for performing separation and sensing processes in flexible reconfigurable microfluidic devices. (paper)

  3. Computational biorheology of human blood flow in health and disease.

    Science.gov (United States)

    Fedosov, Dmitry A; Dao, Ming; Karniadakis, George Em; Suresh, Subra

    2014-02-01

    Hematologic disorders arising from infectious diseases, hereditary factors and environmental influences can lead to, and can be influenced by, significant changes in the shape, mechanical and physical properties of red blood cells (RBCs), and the biorheology of blood flow. Hence, modeling of hematologic disorders should take into account the multiphase nature of blood flow, especially in arterioles and capillaries. We present here an overview of a general computational framework based on dissipative particle dynamics (DPD) which has broad applicability in cell biophysics with implications for diagnostics, therapeutics and drug efficacy assessments for a wide variety of human diseases. This computational approach, validated by independent experimental results, is capable of modeling the biorheology of whole blood and its individual components during blood flow so as to investigate cell mechanistic processes in health and disease. DPD is a Lagrangian method that can be derived from systematic coarse-graining of molecular dynamics but can scale efficiently up to arterioles and can also be used to model RBCs down to the spectrin level. We start from experimental measurements of a single RBC to extract the relevant biophysical parameters, using single-cell measurements involving such methods as optical tweezers, atomic force microscopy and micropipette aspiration, and cell-population experiments involving microfluidic devices. We then use these validated RBC models to predict the biorheological behavior of whole blood in healthy or pathological states, and compare the simulations with experimental results involving apparent viscosity and other relevant parameters. While the approach discussed here is sufficiently general to address a broad spectrum of hematologic disorders including certain types of cancer, this paper specifically deals with results obtained using this computational framework for blood flow in malaria and sickle cell anemia. PMID:24419829

  4. The impact of new trends in POCTs for companion diagnostics, non-invasive testing and molecular diagnostics.

    Science.gov (United States)

    Huckle, David

    2015-06-01

    Point-of-care diagnostics have been slowly developing over several decades and have taken on a new importance in current healthcare delivery for both diagnostics and development of new drugs. Molecular diagnostics have become a key driver of technology change and opened up new areas in companion diagnostics for use alongside pharmaceuticals and in new clinical approaches such as non-invasive testing. Future areas involving smartphone and other information technology advances, together with new developments in molecular biology, microfluidics and surface chemistry are adding to advances in the market. The focus for point-of-care tests with molecular diagnostic technologies is focused on advancing effective applications. PMID:25990929

  5. Corrosion and microfluidics in hot water microsystems

    OpenAIRE

    Eriksson, Mimmi

    2013-01-01

    This thesis addresses some important issues when designing microfluidic systems for hot pressurized water. The properties and behavior of water at elevated temperatures and in micro scale is briefly reviewed, and opportunities and possible problems of using hot pressurized water in microfluidic devices are brought up. Experimental work was focused on corrosion resistance for commonly used microsystem materials in hot pressurized water, and the microfluidic behavior for hot pressurized water. ...

  6. Nanostructures for all-polymer microfluidic systems

    DEFF Research Database (Denmark)

    Matschuk, Maria; Bruus, Henrik; Larsen, Niels Bent

    2010-01-01

    antistiction coating was found to improve the replication fidelity (shape and depth) of nanoscale features substantially. Arrays of holes of 50 nm diameter/35 nm depth and 100 nm/100 nm diameter, respectively, were mass-produced in cyclic olefin copolymer (Topas 5013) by injection molding. Polymer microfluidic...... channel chip parts resulted from a separate injection molding process. The microfluidic chip part and the nanostructured chip part were successfully bonded to form a sealed microfluidic system using air plasma assisted thermal bonding....

  7. Applications of Microfluidics in Stem Cell Biology

    OpenAIRE

    Zhang, Qiucen; Austin, Robert H.

    2012-01-01

    Stem cell research can significantly benefit from recent advances of microfluidics technology. In a rationally designed microfluidics device, analyses of stem cells can be done in a much deeper and wider way than in a conventional tissue culture dish. Miniaturization makes analyses operated in a high-throughput fashion, while controls of fluids help to reconstruct the physiological environments. Through integration with present characterization tools like fluorescent microscope, microfluidics...

  8. Microfluidics for optics and quantitative cell biology

    OpenAIRE

    Campbell, James Kyle

    2008-01-01

    Microfluidics is a quickly expanding field with numerous applications. The advent of rapid-prototyping and soft- lithography allow for easy and inexpensive fabrication of microfluidic devices. Fluid manipulation on the microscale allows for new functionalities of devices and components not available on the macroscale. Fluid flows on the microscale are laminar with chemical mixing defined strictly by diffusion allowing us to design microfluidic devices with precise control of fluid flow and ch...

  9. Microsphere integrated microfluidic disk: synergy of two techniques for rapid and ultrasensitive dengue detection

    Science.gov (United States)

    Hosseini, Samira; Aeinehvand, Mohammad M.; Uddin, Shah M.; Benzina, Abderazak; Rothan, Hussin A.; Yusof, Rohana; Koole, Leo H.; Madou, Marc J.; Djordjevic, Ivan; Ibrahim, Fatimah

    2015-11-01

    The application of microfluidic devices in diagnostic systems is well-established in contemporary research. Large specific surface area of microspheres, on the other hand, has secured an important position for their use in bioanalytical assays. Herein, we report a combination of microspheres and microfluidic disk in a unique hybrid platform for highly sensitive and selective detection of dengue virus. Surface engineered polymethacrylate microspheres with carefully designed functional groups facilitate biorecognition in a multitude manner. In order to maximize the utility of the microspheres’ specific surface area in biomolecular interaction, the microfluidic disk was equipped with a micromixing system. The mixing mechanism (microballoon mixing) enhances the number of molecular encounters between spheres and target analyte by accessing the entire sample volume more effectively, which subsequently results in signal amplification. Significant reduction of incubation time along with considerable lower detection limits were the prime motivations for the integration of microspheres inside the microfluidic disk. Lengthy incubations of routine analytical assays were reduced from 2 hours to 5 minutes while developed system successfully detected a few units of dengue virus. Obtained results make this hybrid microsphere-microfluidic approach to dengue detection a promising avenue for early detection of this fatal illness.

  10. Ultrasensitive, multiplexed detection of cancer biomarkers directly in serum by using a quantum dot-based microfluidic protein chip.

    Science.gov (United States)

    Hu, Mei; Yan, Juan; He, Yao; Lu, Haoting; Weng, Lixing; Song, Shiping; Fan, Chunhai; Wang, Lianhui

    2010-01-26

    Sensitive and selective detection for cancer biomarkers are critical in cancer clinical diagnostics. Here we developed a microfluidic protein chip for an ultrasensitive and multiplexed assay of cancer biomarkers. Aqueous-phase-synthesized CdTe/CdS quantum dots (aqQDs) were employed as fluorescent signal amplifiers to improve the detection sensitivity. Secondary antibodies (goat anti-mouse IgG) were conjugated to luminescent CdTe/CdS QDs to realize a versatile fluorescent probe that could be used for multiplexed detection in both sandwich and reverse phase immunoassays. We found that our microfluidic protein chip not only possessed ultrahigh femtomolar sensitivity for cancer biomarkers, but was selective enough to be directly used in serum. This protein chip thus combines the high-throughput capabilities of a microfluidic network with the high sensitivity and multicolor imaging ability offered by highly fluorescent QDs, which can become a promising diagnostic tool in clinical applications. PMID:20041634

  11. Integrated lenses in polystyrene microfluidic devices

    KAUST Repository

    Fan, Yiqiang

    2013-04-01

    This paper reports a new method for integrating microlenses into microfluidic devices for improved observation. Two demonstration microfluidic devices were provided which were fabricated using this new technique. The integrated microlenses were fabricated using a free-surface thermo-compression molding method on a polystyrene (PS) sheet which was then bonded on top of microfluidic channels as a cover plate, with the convex microlenses providing a magnified image of the channel for the easier observation of the flow in the microchannels. This approach for fabricating the integrated microlens in microfluidic devices is rapid, low cost and without the requirement of cleanroom facilities. © 2013 IEEE.

  12. Controllable preparation of particles with microfluidics

    Institute of Scientific and Technical Information of China (English)

    Guangsheng Luo; Le Du; Yujun Wang; Yangcheng Lu; Jianhong Xu

    2011-01-01

    This paper reviews recent development and achievements in controllable preparation of nanoparticles,micron spherical and non-spherical particles,using microfluidics.A variety of synthesis strategies are presented and compared,including single-phase and multiphase microflows.The main structures of microfluidic devices and the fundamental principles of microflows for particle preparation are summarized and identified.The controllability of particle size,size distribution,crystal structure,morphology,physical and chemical properties,is examined in terms of the special features of microfluidic reactors.An outlook on opinions and predictions concerning the future development of powder technology with microfluidics is specially provided.

  13. High-throughput microfluidic line scan imaging for cytological characterization

    Science.gov (United States)

    Hutcheson, Joshua A.; Powless, Amy J.; Majid, Aneeka A.; Claycomb, Adair; Fritsch, Ingrid; Balachandran, Kartik; Muldoon, Timothy J.

    2015-03-01

    Imaging cells in a microfluidic chamber with an area scan camera is difficult due to motion blur and data loss during frame readout causing discontinuity of data acquisition as cells move at relatively high speeds through the chamber. We have developed a method to continuously acquire high-resolution images of cells in motion through a microfluidics chamber using a high-speed line scan camera. The sensor acquires images in a line-by-line fashion in order to continuously image moving objects without motion blur. The optical setup comprises an epi-illuminated microscope with a 40X oil immersion, 1.4 NA objective and a 150 mm tube lens focused on a microfluidic channel. Samples containing suspended cells fluorescently stained with 0.01% (w/v) proflavine in saline are introduced into the microfluidics chamber via a syringe pump; illumination is provided by a blue LED (455 nm). Images were taken of samples at the focal plane using an ELiiXA+ 8k/4k monochrome line-scan camera at a line rate of up to 40 kHz. The system's line rate and fluid velocity are tightly controlled to reduce image distortion and are validated using fluorescent microspheres. Image acquisition was controlled via MATLAB's Image Acquisition toolbox. Data sets comprise discrete images of every detectable cell which may be subsequently mined for morphological statistics and definable features by a custom texture analysis algorithm. This high-throughput screening method, comparable to cell counting by flow cytometry, provided efficient examination including counting, classification, and differentiation of saliva, blood, and cultured human cancer cells.

  14. Microfluidic bioreactors for culture of non-adherent cells

    DEFF Research Database (Denmark)

    Shah, Pranjul Jaykumar; Vedarethinam, Indumathi; Kwasny, Dorota;

    2011-01-01

    Microfluidic bioreactors (μBR) are becoming increasingly popular for cell culture, sample preparation and analysis in case of routine genetic and clinical diagnostics. We present a novel μBR for non-adherent cells designed to mimic in vivo perfusion of cells based on diffusion of media through a...... sandwiched membrane. The culture chamber and perfusion chamber are separated by a sandwiched membrane and each chamber has separate inlet/outlets for easy loading/unloading of cells and perfusion of the media. The perfusion of media and exchange of nutrients occur through the sandwiched membrane, which was...... of CFSE staining and subsequent counting in a flow cytometer. To conclude on the applicability of μBR for genetic diagnostics, we prepare chromosome spreads on glass slides from the cultured samples, which is the primary step for metaphase FISH analysis....

  15. Microfluidics in amino acid analysis.

    Science.gov (United States)

    Pumera, Martin

    2007-07-01

    Microfluidic devices have been widely used to derivatize, separate, and detect amino acids employing many different strategies. Virtually zero-dead volume interconnections and fast mass transfer in small volume microchannels enable dramatic increases in on-chip derivatization reaction speed, while only minute amounts of sample and reagent are needed. Due to short channel path, fast subsecond separations can be carried out. With sophisticated miniaturized detectors, the whole analytical process can be integrated on one platform. This article reviews developments of lab-on-chip technology in amino acid analysis, it shows important design features such as sample preconcentration, precolumn and postcolumn amino acid derivatization, and unlabeled and labeled amino acid detection with focus on advanced designs. The review also describes important biomedical and space exploration applications of amino acid analysis on microfluidic devices. PMID:17542043

  16. Evaluation of an automated rapid diagnostic assay for detection of Gram-negative bacteria and their drug-resistance genes in positive blood cultures.

    Directory of Open Access Journals (Sweden)

    Masayoshi Tojo

    Full Text Available We evaluated the performance of the Verigene Gram-Negative Blood Culture Nucleic Acid Test (BC-GN; Nanosphere, Northbrook, IL, USA, an automated multiplex assay for rapid identification of positive blood cultures caused by 9 Gram-negative bacteria (GNB and for detection of 9 genes associated with β-lactam resistance. The BC-GN assay can be performed directly from positive blood cultures with 5 minutes of hands-on and 2 hours of run time per sample. A total of 397 GNB positive blood cultures were analyzed using the BC-GN assay. Of the 397 samples, 295 were simulated samples prepared by inoculating GNB into blood culture bottles, and the remaining were clinical samples from 102 patients with positive blood cultures. Aliquots of the positive blood cultures were tested by the BC-GN assay. The results of bacterial identification between the BC-GN assay and standard laboratory methods were as follows: Acinetobacter spp. (39 isolates for the BC-GN assay/39 for the standard methods, Citrobacter spp. (7/7, Escherichia coli (87/87, Klebsiella oxytoca (13/13, and Proteus spp. (11/11; Enterobacter spp. (29/30; Klebsiella pneumoniae (62/72; Pseudomonas aeruginosa (124/125; and Serratia marcescens (18/21; respectively. From the 102 clinical samples, 104 bacterial species were identified with the BC-GN assay, whereas 110 were identified with the standard methods. The BC-GN assay also detected all β-lactam resistance genes tested (233 genes, including 54 bla(CTX-M, 119 bla(IMP, 8 bla(KPC, 16 bla(NDM, 24 bla(OXA-23, 1 bla(OXA-24/40, 1 bla(OXA-48, 4 bla(OXA-58, and 6 blaVIM. The data shows that the BC-GN assay provides rapid detection of GNB and β-lactam resistance genes in positive blood cultures and has the potential to contributing to optimal patient management by earlier detection of major antimicrobial resistance genes.

  17. Microfluidic cryofixation for correlative microscopy.

    OpenAIRE

    Mejia, Y.; Feindt, H.; Zhang, D.(Department of Physics, The University of Michigan, Ann Arbor, MI, United States of America); Steltenkamp, S.; Burg, T.

    2014-01-01

    Cryofixation yields outstanding ultrastructural preservation of cells for electron microscopy, but current methods disrupt live cell imaging. Here we demonstrate a microfluidic approach that enables cryofixation to be performed directly in the light microscope with millisecond time resolution and at atmospheric pressure. This will provide a link between imaging/stimulation of live cells and post-fixation optical, electron, or X-ray microscopy.

  18. Microfluidic systems for cell lysis

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Ivona; Grym, Jakub; Klepárník, Karel; Foret, František

    2006. [Annual European Conference on Micro&Nanoscale Technologies for the Biosciences /10./. 14.11.2006-16.11.2006, Montreux] R&D Projects: GA AV ČR IAA400310506; GA AV ČR KAN400310651; GA MŠk LC06023; GA ČR GA203/06/1685 Institutional research plan: CEZ:AV0Z40310501 Keywords : cell lysis * yeast cells * microfluidic device Subject RIV: CB - Analytical Chemistry, Separation

  19. Liquid dielectrophoresis and surface microfluidics

    OpenAIRE

    Kaler, Karan V. I. S.; Prakash, Ravi; Chugh, Dipankar

    2010-01-01

    Liquid dielectrophoresis (L-DEP), when deployed at microscopic scales on top of hydrophobic surfaces, offers novel ways of rapid and automated manipulation of very small amounts of polar aqueous samples for microfluidic applications and development of laboratory-on-a-chip devices. In this article we highlight some of the more recent developments and applications of L-DEP in handling and processing of various types of aqueous samples and reagents of biological relevance including emulsions usi...

  20. Next generation PCR microfluidic system

    OpenAIRE

    Morris, Angela; Curtin, Damian; McGuire, David; Witherbee, Bryan; Barrett, Brian; Kinahan, David; Sayers, Michael; Sirr, Noel; Hou, Xiaona; Aguanno, Mauro; King, Damien; McCarthy, Conor; Chawke, Brian; Doolan, David; O'Doherty, Sinead

    2010-01-01

    Stokes Bio, founded in 2005, develops innovative microfluidic technologies. In 2008 in collaboration with Monsanto, an application driven development for a high-throughput instrument in the detection and characterisation of Single Nucleotide Polymorphisms (SNPs) in agricultural crops was initiated. Stokes technology is designed to generate aqueous nanolitre scale droplets of reagents and samples, wrapped in a carrier fluid from standard microtitre plates and to mix them using Stokes ...

  1. Self-assembly via microfluidics

    OpenAIRE

    Wang, Lei; Sánchez, Samuel

    2015-01-01

    The self-assembly of amphiphilic building blocks has attracted extensive interest in myriad fields in recent years, due to their great potential in the nanoscale design of functional hybrid materials. Microfluidic techniques provide an intriguing method to control kinetic aspects of the self-assembly of molecular amphiphiles by the facile adjustment of the hydrodynamics of the fluids. Up to now, there have been several reports about one-step direct self-assembly of different building blocks w...

  2. Multidimensional bioseparation with modular microfluidics

    Science.gov (United States)

    Chirica, Gabriela S.; Renzi, Ronald F.

    2013-08-27

    A multidimensional chemical separation and analysis system is described including a prototyping platform and modular microfluidic components capable of rapid and convenient assembly, alteration and disassembly of numerous candidate separation systems. Partial or total computer control of the separation system is possible. Single or multiple alternative processing trains can be tested, optimized and/or run in parallel. Examples related to the separation and analysis of human bodily fluids are given.

  3. A three-dimensional cell-laden microfluidic chip for in vitro drug metabolism detection

    International Nuclear Information System (INIS)

    Three-dimensional tissue platforms are rapidly becoming the method of choice for quantification of the heterogeneity of cell populations for many diagnostic and drug therapy applications. Microfluidic sensors and the integration of sensors with microfluidic systems are often described as miniature versions of their macro-scale counterparts. This technology presents unique advantages for handling costly and difficult-to-obtain samples and reagents as a typical system requires between 100 nL to 10 µL of working fluid. The fabrication of a fully functional cell-based biosensor utilizes both biological patterning and microfabrication techniques. A digital micro-mirror (photolithographic) system is initiated to construct the tissue platform while a cell printer is used to precisely embed the cells within the construct. Tissue construct developed with these technologies will provide an early diagnostic of a drug's potential use. A three-dimensional interconnected microfluidic environment has the potential to eliminate the limitations of the traditional mainstays of two-dimensional investigations. This paper illustrates an economical and an innovative approach of fabricating a three-dimensional cell-laden microfluidic chip for detecting drug metabolism. (paper)

  4. Laboratory diagnosis of malaria by conventional peripheral blood smear examination with Quantitative Buffy Coat (QBC) and Rapid Diagnostic Tests (RDT) - A comparative study

    OpenAIRE

    Bhat Sandhya K; Sastry Apurba S; Nagaraj E.R.; Sharadadevi Mannur; Sastry Anand S

    2012-01-01

    Aim: Rapid diagnosis is prerequisite for effective treatment and reducing mortality and morbidity of malaria. Microscopy has been the Gold standard for malaria diagnosis for decades. Recently, many new rapid diagnostic tests like Quantitative Buffy Coat (QBC) examination and rapid antigen detection methods are being widely used. We made an attempt to compare peripheral smear, QBC and rapid antigen detection methods for the diagnosis of malaria. Materials and Methods: A total number of 500 sam...

  5. Microfluidic devices, systems, and methods for quantifying particles using centrifugal force

    Energy Technology Data Exchange (ETDEWEB)

    Schaff, Ulrich Y.; Sommer, Gregory J.; Singh, Anup K.

    2015-11-17

    Embodiments of the present invention are directed toward microfluidic systems, apparatus, and methods for measuring a quantity of cells in a fluid. Examples include a differential white blood cell measurement using a centrifugal microfluidic system. A method may include introducing a fluid sample containing a quantity of cells into a microfluidic channel defined in part by a substrate. The quantity of cells may be transported toward a detection region defined in part by the substrate, wherein the detection region contains a density media, and wherein the density media has a density lower than a density of the cells and higher than a density of the fluid sample. The substrate may be spun such that at least a portion of the quantity of cells are transported through the density media. Signals may be detected from label moieties affixed to the cells.

  6. Rapid fabrication of microfluidic chips based on the simplest LED lithography

    International Nuclear Information System (INIS)

    Microfluidic chips are generally fabricated by a soft lithography method employing commercial lithography equipment. These heavy machines require a critical room environment and high lamp power, and the cost remains too high for most normal laboratories. Here we present a novel microfluidics fabrication method utilizing a portable ultraviolet (UV) LED as an alternative UV source for photolithography. With this approach, we can repeat several common microchannels as do these conventional commercial exposure machines, and both the verticality of the channel sidewall and lithography resolution are proved to be acceptable. Further microfluidics applications such as mixing, blood typing and microdroplet generation are implemented to validate the practicability of the chips. This simple but innovative method decreases the cost and requirement of chip fabrication dramatically and may be more popular with ordinary laboratories. (paper)

  7. Clogging-free microfluidics for continuous size-based separation of microparticles

    Science.gov (United States)

    Yoon, Yousang; Kim, Seonil; Lee, Jusin; Choi, Jaewoong; Kim, Rae-Kwon; Lee, Su-Jae; Sul, Onejae; Lee, Seung-Beck

    2016-01-01

    In microfluidic filtration systems, one of the leading obstacles to efficient, continuous operation is clogging of the filters. Here, we introduce a lateral flow microfluidic sieving (μ-sieving) technique to overcome clogging and to allow continuous operation of filter based microfluidic separation. A low frequency mechanical oscillation was added to the fluid flow, which made possible the release of aggregated unwanted polystyrene (PS) particles trapped between the larger target PS particles in the filter demonstrating continuous μ-sieving operation. We achieved collection of the target PS particles with 100% separation efficiency. Also, on average, more than 98% of the filtered target particles were retrieved after the filtration showing high retrieval rates. Since the oscillation was applied to the fluid but not to the microfluidic filter system, mechanical stresses to the system was minimized and no additional fabrication procedures were necessary. We also applied the μ-sieving technique to the separation of cancer cells (MDA-MB-231) from whole blood and showed that the fluidic oscillations prevented the filters from being blocked by the filtered cancer cells allowing continuous microfluidic separation with high efficiency. PMID:27198601

  8. Clogging-free microfluidics for continuous size-based separation of microparticles.

    Science.gov (United States)

    Yoon, Yousang; Kim, Seonil; Lee, Jusin; Choi, Jaewoong; Kim, Rae-Kwon; Lee, Su-Jae; Sul, Onejae; Lee, Seung-Beck

    2016-01-01

    In microfluidic filtration systems, one of the leading obstacles to efficient, continuous operation is clogging of the filters. Here, we introduce a lateral flow microfluidic sieving (μ-sieving) technique to overcome clogging and to allow continuous operation of filter based microfluidic separation. A low frequency mechanical oscillation was added to the fluid flow, which made possible the release of aggregated unwanted polystyrene (PS) particles trapped between the larger target PS particles in the filter demonstrating continuous μ-sieving operation. We achieved collection of the target PS particles with 100% separation efficiency. Also, on average, more than 98% of the filtered target particles were retrieved after the filtration showing high retrieval rates. Since the oscillation was applied to the fluid but not to the microfluidic filter system, mechanical stresses to the system was minimized and no additional fabrication procedures were necessary. We also applied the μ-sieving technique to the separation of cancer cells (MDA-MB-231) from whole blood and showed that the fluidic oscillations prevented the filters from being blocked by the filtered cancer cells allowing continuous microfluidic separation with high efficiency. PMID:27198601

  9. Reduced-gravity environment hardware demonstrations of a prototype miniaturized flow cytometer and companion microfluidic mixing technology.

    Science.gov (United States)

    Phipps, William S; Yin, Zhizhong; Bae, Candice; Sharpe, Julia Z; Bishara, Andrew M; Nelson, Emily S; Weaver, Aaron S; Brown, Daniel; McKay, Terri L; Griffin, DeVon; Chan, Eugene Y

    2014-01-01

    Until recently, astronaut blood samples were collected in-flight, transported to earth on the Space Shuttle, and analyzed in terrestrial laboratories. If humans are to travel beyond low Earth orbit, a transition towards space-ready, point-of-care (POC) testing is required. Such testing needs to be comprehensive, easy to perform in a reduced-gravity environment, and unaffected by the stresses of launch and spaceflight. Countless POC devices have been developed to mimic laboratory scale counterparts, but most have narrow applications and few have demonstrable use in an in-flight, reduced-gravity environment. In fact, demonstrations of biomedical diagnostics in reduced gravity are limited altogether, making component choice and certain logistical challenges difficult to approach when seeking to test new technology. To help fill the void, we are presenting a modular method for the construction and operation of a prototype blood diagnostic device and its associated parabolic flight test rig that meet the standards for flight-testing onboard a parabolic flight, reduced-gravity aircraft. The method first focuses on rig assembly for in-flight, reduced-gravity testing of a flow cytometer and a companion microfluidic mixing chip. Components are adaptable to other designs and some custom components, such as a microvolume sample loader and the micromixer may be of particular interest. The method then shifts focus to flight preparation, by offering guidelines and suggestions to prepare for a successful flight test with regard to user training, development of a standard operating procedure (SOP), and other issues. Finally, in-flight experimental procedures specific to our demonstrations are described. PMID:25490614

  10. Materials for microfluidic chip fabrication.

    Science.gov (United States)

    Ren, Kangning; Zhou, Jianhua; Wu, Hongkai

    2013-11-19

    Through manipulating fluids using microfabricated channel and chamber structures, microfluidics is a powerful tool to realize high sensitive, high speed, high throughput, and low cost analysis. In addition, the method can establish a well-controlled microenivroment for manipulating fluids and particles. It also has rapid growing implementations in both sophisticated chemical/biological analysis and low-cost point-of-care assays. Some unique phenomena emerge at the micrometer scale. For example, reactions are completed in a shorter amount of time as the travel distances of mass and heat are relatively small; the flows are usually laminar; and the capillary effect becomes dominant owing to large surface-to-volume ratios. In the meantime, the surface properties of the device material are greatly amplified, which can lead to either unique functions or problems that we would not encounter at the macroscale. Also, each material inherently corresponds with specific microfabrication strategies and certain native properties of the device. Therefore, the material for making the device plays a dominating role in microfluidic technologies. In this Account, we address the evolution of materials used for fabricating microfluidic chips, and discuss the application-oriented pros and cons of different materials. This Account generally follows the order of the materials introduced to microfluidics. Glass and silicon, the first generation microfluidic device materials, are perfect for capillary electrophoresis and solvent-involved applications but expensive for microfabriaction. Elastomers enable low-cost rapid prototyping and high density integration of valves on chip, allowing complicated and parallel fluid manipulation and in-channel cell culture. Plastics, as competitive alternatives to elastomers, are also rapid and inexpensive to microfabricate. Their broad variety provides flexible choices for different needs. For example, some thermosets support in-situ fabrication of

  11. Opportunities for microfluidic technologies in synthetic biology

    OpenAIRE

    Gulati, Shelly; Rouilly, Vincent; Niu, Xize; Chappell, James; Kitney, Richard I.; Edel, Joshua B.; Paul S Freemont; deMello, Andrew J.

    2009-01-01

    We introduce microfluidics technologies as a key foundational technology for synthetic biology experimentation. Recent advances in the field of microfluidics are reviewed and the potential of such a technological platform to support the rapid development of synthetic biology solutions is discussed.

  12. Modular microfluidic system for biological sample preparation

    Energy Technology Data Exchange (ETDEWEB)

    Rose, Klint A.; Mariella, Jr., Raymond P.; Bailey, Christopher G.; Ness, Kevin Dean

    2015-09-29

    A reconfigurable modular microfluidic system for preparation of a biological sample including a series of reconfigurable modules for automated sample preparation adapted to selectively include a) a microfluidic acoustic focusing filter module, b) a dielectrophoresis bacteria filter module, c) a dielectrophoresis virus filter module, d) an isotachophoresis nucleic acid filter module, e) a lyses module, and f) an isotachophoresis-based nucleic acid filter.

  13. Cell Culture Microfluidic Biochips: Experimental Throughput Maximization

    DEFF Research Database (Denmark)

    Minhass, Wajid Hassan; Pop, Paul; Madsen, Jan;

    2011-01-01

    Microfluidic biochips offer a promising alternative to a conventional biochemical laboratory, integrating all necessary functionalities on-chip in order to perform biochemical applications. Researchers have started to propose computer-aided design tools for the synthesis of such biochips. Our focus...... Annealing metaheuristic for experimental design generation for the cell culture microfluidic biochips, and we have evaluated our approach using multiple experimental setups....

  14. Principles, Techniques, and Applications of Tissue Microfluidics

    Science.gov (United States)

    Wade, Lawrence A.; Kartalov, Emil P.; Shibata, Darryl; Taylor, Clive

    2011-01-01

    The principle of tissue microfluidics and its resultant techniques has been applied to cell analysis. Building microfluidics to suit a particular tissue sample would allow the rapid, reliable, inexpensive, highly parallelized, selective extraction of chosen regions of tissue for purposes of further biochemical analysis. Furthermore, the applicability of the techniques ranges beyond the described pathology application. For example, they would also allow the posing and successful answering of new sets of questions in many areas of fundamental research. The proposed integration of microfluidic techniques and tissue slice samples is called "tissue microfluidics" because it molds the microfluidic architectures in accordance with each particular structure of each specific tissue sample. Thus, microfluidics can be built around the tissues, following the tissue structure, or alternatively, the microfluidics can be adapted to the specific geometry of particular tissues. By contrast, the traditional approach is that microfluidic devices are structured in accordance with engineering considerations, while the biological components in applied devices are forced to comply with these engineering presets.

  15. Detection methods for centrifugal microfluidic platforms

    DEFF Research Database (Denmark)

    Burger, Robert; Amato, Letizia; Boisen, Anja

    2016-01-01

    Centrifugal microfluidics has attracted much interest from academia as well as industry, since it potentially offers solutions for affordable, user-friendly and portable biosensing. A wide range of so-called fluidic unit operations, e.g. mixing, metering, liquid routing, and particle separation...... centrifugal microfluidics platform and cover optical as well as mechanical and electrical detection principles....

  16. Droplet-based Biosensing for Lab-on-a-Chip, Open Microfluidics Platforms

    Directory of Open Access Journals (Sweden)

    Piyush Dak

    2016-04-01

    Full Text Available Low cost, portable sensors can transform health care by bringing easily available diagnostic devices to low and middle income population, particularly in developing countries. Sample preparation, analyte handling and labeling are primary cost concerns for traditional lab-based diagnostic systems. Lab-on-a-chip (LoC platforms based on droplet-based microfluidics promise to integrate and automate these complex and expensive laboratory procedures onto a single chip; the cost will be further reduced if label-free biosensors could be integrated onto the LoC platforms. Here, we review some recent developments of label-free, droplet-based biosensors, compatible with “open” digital microfluidic systems. These low-cost droplet-based biosensors overcome some of the fundamental limitations of the classical sensors, enabling timely diagnosis. We identify the key challenges that must be addressed to make these sensors commercially viable and summarize a number of promising research directions.

  17. Practical Packaging Technology for Microfluidic Systems

    International Nuclear Information System (INIS)

    This paper presents the technology for the design, fabrication, and characterization of a microfluidic system interface (MSI): the purpose of this technology is to enable the integration of complex microfluidic systems. The MSI technology can be applied in a simple manner for realizing complex arrangements of microfluidic interconnects, integrated microvalves for fluid control, and optical windows for on-chip optical processes. A microfluidic system for the preparation of genetic samples was used as the test vehicle to prove the effectiveness of the MSI technology for packaging complex microfluidic systems with multiple functionalities. The miniaturized genetic sample preparation system comprised several functional compartments, including compartments for cell purification, cell separation, cell lysis, solid-phase DNA extraction, polymerase chain reaction, and capillary electrophoresis. Additionally, the functional operation of the solid-phase extraction and PCR thermocycling compartments was demonstrated by using the MSI

  18. Manipulation of microfluidic droplets by electrorheological fluid

    KAUST Repository

    Zhang, Menying

    2009-09-01

    Microfluidics, especially droplet microfluidics, attracts more and more researchers from diverse fields, because it requires fewer materials and less time, produces less waste and has the potential of highly integrated and computer-controlled reaction processes for chemistry and biology. Electrorheological fluid, especially giant electrorheological fluid (GERF), which is considered as a kind of smart material, has been applied to the microfluidic systems to achieve active and precise control of fluid by electrical signal. In this review article, we will introduce recent results of microfluidic droplet manipulation, GERF and some pertinent achievements by introducing GERF into microfluidic system: digital generation, manipulation of "smart droplets" and droplet manipulation by GERF. Once it is combined with real-time detection, integrated chip with multiple functions can be realized. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

  19. Diagnostic potential for gold nanoparticle-based surface-enhanced Raman spectroscopy to provide colorectal cancer screening using blood serum sample

    Science.gov (United States)

    Lin, Duo; Feng, Shangyuan; Pan, Jianji; Chen, Yanping; Lin, Juqiang; Sun, Liqing; Chen, Rong

    2012-03-01

    Surface-enhanced Raman spectroscopy (SERS) is a vibrational spectroscopic technique that is capable of probing the biomolecular changes associated with diseased transformation. The objective of our study was to explore gold nanoparticle based SERS to obtain blood serum biochemical information for non-invasive colorectal cancer detection. SERS measurements were performed on two groups of blood serum samples: one group from patients (n = 38) with pathologically confirmed colorectal cancer and the other group from healthy volunteers (control subjects, n = 45). Tentative assignments of the Raman bands in the measured SERS spectra suggested interesting cancer specific biomolecular changes, including an increase in the relative amounts of nucleic acid, a decrease in the percentage of saccharide and proteins contents in the blood serum of colorectal cancer patients as compared to that of healthy subjects. Principal component analysis (PCA) of the measured SERS spectra separated the spectral features of the two groups into two distinct clusters with little overlaps. Linear discriminate analysis (LDA) based on the PCA generated features differentiated the nasopharyngeal cancer SERS spectra from normal SERS spectra with high sensitivity (97.4%) and specificity (100%). The results from this exploratory study demonstrated that gold nanoparticle based SERS serum analysis combined with PCA-LDA has tremendous potential for the non-invasive detection of colorectal cancers.

  20. Inversion of hematocrit partition at microfluidic bifurcations

    CERN Document Server

    Shen, Zaiyi; Kaoui, Badr; Polack, Benoît; Harting, Jens; Misbah, Chaouqi; Podgorski, Thomas

    2016-01-01

    Partitioning of red blood cells (RBCs) at the level of bifurcations in the microcirculatory system affects many physiological functions yet it remains poorly understood. We address this problem by using T-shaped microfluidic bifurcations as a model. Our computer simulations and in vitro experiments reveal that the hematocrit ($\\phi_0$) partition depends strongly on RBC deformability, as long as $\\phi_0 <20$% (within the normal range in microcirculation), and can even lead to complete deprivation of RBCs in a child branch. Furthermore, we discover a deviation from the Zweifach-Fung effect which states that the child branch with lower flow rate recruits less RBCs than the higher flow rate child branch. At small enough $\\phi_0$, we get the inverse scenario, and the hematocrit in the lower flow rate child branch is even higher than in the parent vessel. We explain this result by an intricate up-stream RBC organization and we highlight the extreme dependence of RBC transport on geometrical and cell mechanical p...

  1. Optical biosensor system with integrated microfluidic sample preparation and TIRF based detection

    Science.gov (United States)

    Gilli, Eduard; Scheicher, Sylvia R.; Suppan, Michael; Pichler, Heinz; Rumpler, Markus; Satzinger, Valentin; Palfinger, Christian; Reil, Frank; Hajnsek, Martin; Köstler, Stefan

    2013-05-01

    There is a steadily growing demand for miniaturized bioanalytical devices allowing for on-site or point-of-care detection of biomolecules or pathogens in applications like diagnostics, food testing, or environmental monitoring. These, so called labs-on-a-chip or micro-total analysis systems (μ-TAS) should ideally enable convenient sample-in - result-out type operation. Therefore, the entire process from sample preparation, metering, reagent incubation, etc. to detection should be performed on a single disposable device (on-chip). In the early days such devices were mainly fabricated using glass or silicon substrates and adapting established fabrication technologies from the electronics and semiconductor industry. More recently, the development focuses on the use of thermoplastic polymers as they allow for low-cost high volume fabrication of disposables. One of the most promising materials for the development of plastic based lab-on-achip systems are cyclic olefin polymers and copolymers (COP/COC) due to their excellent optical properties (high transparency and low autofluorescence) and ease of processing. We present a bioanalytical system for whole blood samples comprising a disposable plastic chip based on TIRF (total internal reflection fluorescence) optical detection. The chips were fabricated by compression moulding of COP and microfluidic channels were structured by hot embossing. These microfluidic structures integrate several sample pretreatment steps. These are the separation of erythrocytes, metering of sample volume using passive valves, and reagent incubation for competitive bioassays. The surface of the following optical detection zone is functionalized with specific capture probes in an array format. The plastic chips comprise dedicated structures for simple and effective coupling of excitation light from low-cost laser diodes. This enables TIRF excitation of fluorescently labeled probes selectively bound to detection spots at the microchannel surface

  2. Optical diagnostics of osteoblast cells and osteogenic drug screening

    Science.gov (United States)

    Kolanti, Elayaraja; Veerla, Sarath C.; Khajuria, Deepak K.; Roy Mahapatra, D.

    2016-02-01

    Microfluidic device based diagnostics involving optical fibre path, in situ imaging and spectroscopy are gaining importance due to recent advances in diagnostics instrumentation and methods, besides other factors such as low amount of reagent required for analysis, short investigation times, and potential possibilities to replace animal model based study in near future. It is possible to grow and monitor tissues in vitro in microfluidic lab-on-chip. It may become a transformative way of studying how cells interact with drugs, pathogens and biomaterials in physiologically relevant microenvironments. To a large extent, progress in developing clinically viable solutions has been constrained because of (i) contradiction between in vitro and in vivo results and (ii) animal model based and clinical studies which is very expensive. Our study here aims to evaluate the usefulness of microfluidic device based 3D tissue growth and monitoring approach to better emulate physiologically and clinically relevant microenvironments in comparison to conventional in vitro 2D culture. Moreover, the microfluidic methodology permits precise high-throughput investigations through real-time imaging while using very small amounts of reagents and cells. In the present study, we report on the details of an osteoblast cell based 3D microfluidic platform which we employ for osteogenic drug screening. The drug formulation is functionalized with fluorescence and other biomarkers for imaging and spectroscopy, respectively. Optical fibre coupled paths are used to obtain insight regarding the role of stress/flow pressure fluctuation and nanoparticle-drug concentration on the osteoblast growth and osteogenic properties of bone.

  3. Automated microfluidic DNA/RNA extraction with both disposable and reusable components

    International Nuclear Information System (INIS)

    An automated microfluidic nucleic extraction system was fabricated with a multilayer polydimethylsiloxane (PDMS) structure that consists of sample wells, microvalves, a micropump and a disposable microfluidic silica cartridge. Both the microvalves and micropump structures were fabricated in a single layer and are operated pneumatically using a 100 µm PDMS membrane. To fabricate the disposable microfluidic silica cartridge, two-cavity structures were made in a PDMS replica to fit the stacked silica membranes. A handheld controller for the microvalves and pumps was developed to enable system automation. With purified ribonucleic acid (RNA), whole blood and E. coli samples, the automated microfluidic nucleic acid extraction system was validated with a guanidine-based solid phase extraction procedure. An extraction efficiency of ∼90% for deoxyribonucleic acid (DNA) and ∼54% for RNA was obtained in 12 min from whole blood and E. coli samples, respectively. In addition, the same quantity and quality of extracted DNA was confirmed by polymerase chain reaction (PCR) amplification. The PCR also presented the appropriate amplification and melting profiles. Automated, programmable fluid control and physical separation of the reusable components and the disposable components significantly decrease the assay time and manufacturing cost and increase the flexibility and compatibility of the system with downstream components

  4. Automated microfluidic DNA/RNA extraction with both disposable and reusable components

    Science.gov (United States)

    Kim, Jungkyu; Johnson, Michael; Hill, Parker; Sonkul, Rahul S.; Kim, Jongwon; Gale, Bruce K.

    2012-01-01

    An automated microfluidic nucleic extraction system was fabricated with a multilayer polydimethylsiloxane (PDMS) structure that consists of sample wells, microvalves, a micropump and a disposable microfluidic silica cartridge. Both the microvalves and micropump structures were fabricated in a single layer and are operated pneumatically using a 100 µm PDMS membrane. To fabricate the disposable microfluidic silica cartridge, two-cavity structures were made in a PDMS replica to fit the stacked silica membranes. A handheld controller for the microvalves and pumps was developed to enable system automation. With purified ribonucleic acid (RNA), whole blood and E. coli samples, the automated microfluidic nucleic acid extraction system was validated with a guanidine-based solid phase extraction procedure. An extraction efficiency of ~90% for deoxyribonucleic acid (DNA) and ~54% for RNA was obtained in 12 min from whole blood and E. coli samples, respectively. In addition, the same quantity and quality of extracted DNA was confirmed by polymerase chain reaction (PCR) amplification. The PCR also presented the appropriate amplification and melting profiles. Automated, programmable fluid control and physical separation of the reusable components and the disposable components significantly decrease the assay time and manufacturing cost and increase the flexibility and compatibility of the system with downstream components.

  5. Hydrodynamic guiding for addressing subsets of immobilized cells and molecules in microfluidic systems

    Directory of Open Access Journals (Sweden)

    Beyer Michael

    2003-07-01

    Full Text Available Abstract Background The interest in microfluidics and surface patterning is increasing as the use of these technologies in diverse biomedical applications is substantiated. Controlled molecular and cellular surface patterning is a costly and time-consuming process. Methods for keeping multiple separate experimental conditions on a patterned area are, therefore, needed to amplify the amount of biological information that can be retrieved from a patterned surface area. We describe, in three examples of biomedical applications, how this can be achieved in an open microfluidic system, by hydrodynamically guiding sample fluid over biological molecules and living cells immobilized on a surface. Results A microfluidic format of a standard assay for cell-membrane integrity showed a fast and dose-dependent toxicity of saponin on mammalian cells. A model of the interactions of human mononuclear leukocytes and endothelial cells was established. By contrast to static adhesion assays, cell-cell adhesion in this dynamic model depended on cytokine-mediated activation of both endothelial and blood cells. The microfluidic system allowed the use of unprocessed blood as sample material, and a specific and fast immunoassay for measuring the concentration of C-reactive protein in whole blood was demonstrated. Conclusion The use of hydrodynamic guiding made multiple and dynamic experimental conditions on a small surface area possible. The ability to change the direction of flow and produce two-dimensional grids can increase the number of reactions per surface area even further. The described microfluidic system is widely applicable, and can take advantage of surfaces produced by current and future techniques for patterning in the micro- and nanometer scale.

  6. Development of a rapid diagnostic method for identification of Staphylococcus aureus and antimicrobial resistance in positive blood culture bottles using a PCR-DNA-chromatography method.

    Science.gov (United States)

    Ohshiro, Takeya; Miyagi, Chihiro; Tamaki, Yoshikazu; Mizuno, Takuya; Ezaki, Takayuki

    2016-06-01

    Blood culturing and the rapid reporting of results are essential for infectious disease clinics to obtain bacterial information that can affect patient prognosis. When gram-positive coccoid cells are observed in blood culture bottles, it is important to determine whether the strain is Staphylococcus aureus and whether the strain has resistance genes, such as mecA and blaZ, for proper antibiotic selection. Previous work led to the development of a PCR method that is useful for rapid identification of bacterial species and antimicrobial susceptibility. However, that method has not yet been adopted in community hospitals due to the high cost and methodological complexity. We report here the development of a quick PCR and DNA-chromatography test, based on single-tag hybridization chromatography, that permits detection of S. aureus and the mecA and blaZ genes; results can be obtained within 1 h for positive blood culture bottles. We evaluated this method using 42 clinical isolates. Detection of S. aureus and the resistance genes by the PCR-DNA-chromatography method was compared with that obtained via the conventional identification method and actual antimicrobial susceptibility testing. Our method had a sensitivity of 97.0% and a specificity of 100% for the identification of the bacterial species. For the detection of the mecA gene of S. aureus, the sensitivity was 100% and the specificity was 95.2%. For the detection of the blaZ gene of S. aureus, the sensitivity was 100% and the specificity was 88.9%. The speed and simplicity of this PCR-DNA-chromatography method suggest that our method will facilitate rapid diagnoses. PMID:27056092

  7. Contactless diagnostics of biophysical parameters of skin and blood on the basis of approximating functions for radiation fluxes scattered by skin

    International Nuclear Information System (INIS)

    Approximating expressions are derived to calculate spectral and spatial characteristics of diffuse reflection of light from a two-layer medium mimicking human skin. The effectiveness of the use of these expressions in the optical diagnosis of skin biophysical parameters (tissue scattering parameters, concentration of melanin in the epidermis, concentration of total haemoglobin and bilirubin in the tissues of the dermis) and content of haemoglobin derivatives in blood (oxy-, deoxy-, met-, carboxy- and sulfhaemoglobin) is analysed numerically. The methods are proposed to determine in realtime these parameters without contact of the measuring instrument with the patient's body. (biophotonics)

  8. Contactless diagnostics of biophysical parameters of skin and blood on the basis of approximating functions for radiation fluxes scattered by skin

    Energy Technology Data Exchange (ETDEWEB)

    Lisenko, S A; Kugeiko, M M [Belarusian State University, Minsk (Belarus)

    2014-03-28

    Approximating expressions are derived to calculate spectral and spatial characteristics of diffuse reflection of light from a two-layer medium mimicking human skin. The effectiveness of the use of these expressions in the optical diagnosis of skin biophysical parameters (tissue scattering parameters, concentration of melanin in the epidermis, concentration of total haemoglobin and bilirubin in the tissues of the dermis) and content of haemoglobin derivatives in blood (oxy-, deoxy-, met-, carboxy- and sulfhaemoglobin) is analysed numerically. The methods are proposed to determine in realtime these parameters without contact of the measuring instrument with the patient's body. (biophotonics)

  9. High-throughput microfluidic device for rare cell isolation

    Science.gov (United States)

    Yang, Daniel; Leong, Serena; Lei, Andy; Sohn, Lydia L.

    2015-06-01

    Enumerating and analyzing circulating tumor cells (CTCs)—cells that have been shed from primary solid tumors—can potentially be used to determine patient prognosis and track the progression of disease. There is a great challenge to create an effective platform that can isolate these cells, as they are extremely rare: only 1-10 CTCs are present in a 7.5mL of a cancer patient's peripheral blood. We have developed a novel microfluidic system that can isolate CTC populations label free. Our system consists of a multistage separator that employs inertial migration to sort cells based on size. We demonstrate the feasibility of our device by sorting colloids that are comparable in size to red blood cells (RBCs) and CTCs.

  10. Microfluidic systems for optical sorting

    Czech Academy of Sciences Publication Activity Database

    Ježek, Jan; Pilát, Zdeněk; Šerý, Mojmír; Kaňka, Jan; Samek, Ota; Bernatová, Silvie; Zemánek, Pavel

    Bellingham : SPIE, 2012, 86970W: 1-9. ISBN 978-0-8194-9481-8. [CPS 2012. Czech-Polish-Slovak Optical Conference on Wave and Quantum Aspects of Contemporary Optics /18./. Ostravice (CZ), 03.09.2012-07.09.2012] R&D Projects: GA MPO FR-TI1/433; GA MŠk ED0017/01/01; GA ČR GAP205/11/1687 Institutional support: RVO:68081731 Keywords : microfluidic * cell sorting * optical tweezers * Raman spectroscopy Subject RIV: BH - Optics, Masers, Lasers

  11. Blood Clots

    Science.gov (United States)

    ... Index A-Z Blood Clots Blood clots are semi-solid masses of blood that can be stationary (thrombosis) ... treated? What are blood clots? Blood clots are semi-solid masses of blood. Normally, blood flows freely through ...

  12. A Two-Stage Microfluidic Device for the Isolation and Capture of Circulating Tumor Cells

    Science.gov (United States)

    Cook, Andrew; Belsare, Sayali; Giorgio, Todd; Mu, Richard

    2014-11-01

    Analysis of circulating tumor cells (CTCs) can be critical for studying how tumors grow and metastasize, in addition to personalizing treatment for cancer patients. CTCs are rare events in blood, making it difficult to remove CTCs from the blood stream. Two microfluidic devices have been developed to separate CTCs from blood. The first is a double spiral device that focuses cells into streams, the positions of which are determined by cell diameter. The second device uses ligand-coated magnetic nanoparticles that selectively attach to CTCs. The nanoparticles then pull CTCs out of solution using a magnetic field. These two devices will be combined into a single 2-stage microfluidic device that will capture CTCs more efficiently than either device on its own. The first stage depletes the number of blood cells in the sample by size-based separation. The second stage will magnetically remove CTCs from solution for study and culturing. Thus far, size-based separation has been achieved. Research will also focus on understanding the equations that govern fluid dynamics and magnetic fields in order to determine how the manipulation of microfluidic parameters, such as dimensions and flow rate, will affect integration and optimization of the 2-stage device. NSF-CREST: Center for Physics and Chemistry of Materials. HRD-0420516; Department of Defense, Peer Reviewed Medical Research Program Award W81XWH-13-1-0397.

  13. Laser Ablation of Polymer Microfluidic Devices

    Science.gov (United States)

    Killeen, Kevin

    2004-03-01

    Microfluidic technology is ideal for processing precious samples of limited volumes. Some of the most important classes of biological samples are both high in sample complexity and low in concentration. Combining the elements of sample pre-concentration, chemical separation and high sensitivity detection with chemical identification is essential for realizing a functional microfluidic based analysis system. Direct write UV laser ablation has been used to rapidly fabricate microfluidic devices capable of high performance liquid chromatography (HPLC)-MS. These chip-LC/MS devices use bio-compatible, solvent resistant and flexible polymer materials such as polyimide. A novel microfluidic to rotary valve interface enables, leak free, high pressure fluid switching between multiple ports of the microfluidic chip-LC/MS device. Electrospray tips with outer dimension of 50 um and inner of 15 um are formed by ablating the polymer material concentrically around a multilayer laminated channel structure. Biological samples of digested proteins were used to evaluate the performance of these microfluidic devices. Liquid chromatography separation and similar sample pretreatments have been performed using polymeric microfluidic devices with on-chip separation channels. Mass spectrometry was performed using an Agilent Technologies 1100 series ion trap mass spectrometer. Low fmol amounts of protein samples were positively and routinely identified by searching the MS/MS spectral data against protein databases. The sensitivity and separation performance of the chip-LC devices has been found to be comparable to state of the art nano-electrospray systems.

  14. Magnetophoretic separation of blood cells at the microscale

    CERN Document Server

    Furlani, E P

    2006-01-01

    We present a method and model for the direct and continuous separation of red and white blood cells in plasma. The method is implemented at the microscale using a microfluidic system that consists of an array of integrated soft-magnetic elements embedded beneath a microfluidic channel. The microsystem is passive, and is activated via application of a bias field that magnetizes the elements. Once magnetized, the elements produce a nonuniform magnetic field distribution in the microchannel, which gives rise to a force on blood cells as they pass through the microsystem. In whole blood, white blood cells behave as diamagnetic microparticles while red blood cells exhibit diamagnetic or paramagnetic behavior depending on the oxygenation of their hemoglobin. We develop a mathematical model for predicting the motion of blood cells in the microsystem that takes into account the dominant magnetic, fluidic and buoyant forces on the cells. We use the model to study red/white blood cell transport, and our analysis indica...

  15. Pulsatile microfluidics as an analytical tool for determining the dynamic characteristics of microfluidic systems

    DEFF Research Database (Denmark)

    Vedel, Søren; Olesen, Laurits Højgaard; Bruus, Henrik

    2010-01-01

    An understanding of all fluid dynamic time scales is needed to fully understand and hence exploit the capabilities of fluid flow in microfluidic systems. We propose the use of harmonically oscillating microfluidics as an analytical tool for the deduction of these time scales. Furthermore, we......-filled interconnected elastic microfluidic tubes containing a large, trapped air bubble and driven by a pulsatile pressure difference. We demonstrate good agreement between the system-level model and the experimental results, allowing us to determine the dynamic time scales of the system. However, the generic analysis...... can be applied to all microfluidic systems, both ac and dc....

  16. Frequency-specific flow control in microfluidic circuits with passive elastomeric features

    Science.gov (United States)

    Leslie, Daniel C.; Easley, Christopher J.; Seker, Erkin; Karlinsey, James M.; Utz, Marcel; Begley, Matthew R.; Landers, James P.

    2009-03-01

    A fundamental challenge in the design of microfluidic devices lies in the need to control the transport of fluid according to complex patterns in space and time, and with sufficient accuracy. Although strategies based on externally actuated valves have enabled marked breakthroughs in chip-based analysis, this requires significant off-chip hardware, such as vacuum pumps and switching solenoids, which strongly tethers such devices to laboratory environments. Severing the microfluidic chip from this off-chip hardware would enable a new generation of devices that place the power of microfluidics in a broader range of disciplines. For example, complete on-chip flow control would empower highly portable microfluidic tools for diagnostics, forensics, environmental analysis and food safety, and be particularly useful in field settings where infrastructure is limited. Here, we demonstrate an elegantly simple strategy for flow control: fluidic networks with embedded deformable features are shown to transport fluid selectively in response to the frequency of a time-modulated pressure source. Distinct fluidic flow patterns are activated through the dynamic control of a single pressure input, akin to the analog responses of passive electrical circuits composed of resistors, capacitors and diodes.

  17. Microfluidics Integrated Biosensors: A Leading Technology towards Lab-on-a-Chip and Sensing Applications

    Directory of Open Access Journals (Sweden)

    George Luka

    2015-12-01

    Full Text Available A biosensor can be defined as a compact analytical device or unit incorporating a biological or biologically derived sensitive recognition element immobilized on a physicochemical transducer to measure one or more analytes. Microfluidic systems, on the other hand, provide throughput processing, enhance transport for controlling the flow conditions, increase the mixing rate of different reagents, reduce sample and reagents volume (down to nanoliter, increase sensitivity of detection, and utilize the same platform for both sample preparation and detection. In view of these advantages, the integration of microfluidic and biosensor technologies provides the ability to merge chemical and biological components into a single platform and offers new opportunities for future biosensing applications including portability, disposability, real-time detection, unprecedented accuracies, and simultaneous analysis of different analytes in a single device. This review aims at representing advances and achievements in the field of microfluidic-based biosensing. The review also presents examples extracted from the literature to demonstrate the advantages of merging microfluidic and biosensing technologies and illustrate the versatility that such integration promises in the future biosensing for emerging areas of biological engineering, biomedical studies, point-of-care diagnostics, environmental monitoring, and precision agriculture.

  18. A microfluidic two-pump system inspired by liquid feeding in mosquitoes

    Science.gov (United States)

    Marino, Andrew; Goad, Angela; Stremler, Mark; Socha, John; Jung, Sunghwan

    Mosquitoes feed on nectar and blood using a two-pump system in the head-a smaller cibarial pump in line with a larger a pharyngeal pump, with a valve in between. To suck, mosquitoes transport the liquid (which may be a multi-component viscous fluid, blood) through a long micro-channel, the proboscis. In the engineering realm, microfluidic devices in biomedical applications, such as lab-on-a-chip technology, necessitate implementing a robust pump design to handle clogging and increase flow control compared to a single-pump system. In this talk, we introduce a microfluidic pump design inspired by the mosquito's two-pump system. The pumping performance (flow rate) in presence of impurities (air bubbles, soft clogs) is quantified as a function of phase difference and volume expansion of the pumps, and the elasticity of the valve.

  19. Determining Concentration of Neurotrophic Factors and Neuron Specific Enolase in the Blood of Newborns with Central Nervous System Damages as a New Approach in Clinical Diagnostics

    Directory of Open Access Journals (Sweden)

    M.V. Vedunova

    2015-06-01

    Full Text Available The aim of the investigation is to assess the quantity of brain-derived neurotrophic factor (BDNF, glial cell line-derived neurotrophic factor (GDNF and neuron specific enolase (NSE in plasma of newborns with perinatal hypoxic damage of CNS. Materials and Methods. Neurotrophic factors and NSE enzyme concentrations in plasma of newborns (gestation age 31–42 weeks was studied. The main groups consisted of newborns with the symptoms of perinatal CNS damage (group 1 — with convulsive states, group 2 — with the signs of severe perinatal CNS damage, diagnosed according to physical examination, evaluation of the neurological status dynamics and neurosonographic studies. Control group included healthy neonates. Concentration of BDNF, GDNF (R&D Systems, USA and NSE enzyme (Vector Best, Russia was determined by ELISA kit during hospitalization and on day 10–14 after the rehabilitation therapy. Results. Carried out experiments revealed the significant increase of NSE concentration in plasma of newborns with convulsive states. The higher levels of this enzyme were detected in infants with severe perinatal CNS damage. Moreover, BDNF concentration significantly increases in plasma of patients with the symptoms of severe CNS damage in the period following rehabilitation therapy. These experiments also demonstrate the inverse correlation between BDNF and GDNF levels. It was shown the important prognostic value of BDNF and NSE determination in plasma of newborns with CNS injury. Conclusion. The most diagnostic value for assessing the severity of brain damage in early neonatal period is associated with measurements of NSE and BDNF concentrations in plasma, which allows to use these markers immediately after birth and before the development of neurological symptoms.

  20. Numerical and experimental study of capillary-driven flow of PCR solution in hybrid hydrophobic microfluidic networks.

    Science.gov (United States)

    Ramalingam, Naveen; Warkiani, Majid Ebrahimi; Ramalingam, Neevan; Keshavarzi, Gholamreza; Hao-Bing, Liu; Hai-Qing, Thomas Gong

    2016-08-01

    Capillary-driven microfluidics is essential for development of point-of-care diagnostic micro-devices. Polymerase chain reaction (PCR)-based micro-devices are widely developed and used in such point-of-care settings. It is imperative to characterize the fluid parameters of PCR solution for designing efficient capillary-driven microfluidic networks. Generally, for numeric modelling, the fluid parameters of PCR solution are approximated to that of water. This procedure leads to inaccurate results, which are discrepant to experimental data. This paper describes mathematical modeling and experimental validation of capillary-driven flow inside Poly-(dimethyl) siloxane (PDMS)-glass hybrid micro-channels. Using experimentally measured PCR fluid parameters, the capillary meniscus displacement in PDMS-glass microfluidic ladder network is simulated using computational fluid dynamic (CFD), and experimentally verified to match with the simulated data. PMID:27432321

  1. Passive blood plasma separation at the microscale: a review of design principles and microdevices

    Science.gov (United States)

    Tripathi, Siddhartha; Bala Varun Kumar, Y. V.; Prabhakar, Amit; Joshi, Suhas S.; Agrawal, Amit

    2015-08-01

    Blood plasma separation is vital in the field of diagnostics and health care. Due to the inherent advantages obtained in the transition to microscale, the recent trend in these fields is a rapid shift towards the miniaturization of complex macro processes. Plasma separation in microdevices is one such process which has received extensive attention from researchers globally. Blood plasma separation techniques based on microfluidic platforms can be broadly classified into two categories. While active techniques utilize external force fields for separation, the passive techniques are dependent on biophysical effects, cell behavior, hydrodynamic forces and channel geometry for blood plasma separation. In general, passive separation methods are favored in comparison to active methods because they tend to avoid design complexities and are relatively easy to integrate with biosensors; additionally they are cost effective. Here we review passive separation techniques demonstrating separation and blood behavior at microscale. We present an extensive review of relevant biophysical laws, along with experimental details of various passive separation techniques and devices exploiting these physical effects. The relative performances, and the advantages and disadvantages of microdevices discussed in the literature, are compared and future challenges are brought about.

  2. The diagnostic value of angioscintigraphy with sup(99m)Tc-labelled red blood cells for detection of deep vein thrombosis

    International Nuclear Information System (INIS)

    Angioscintigraphy with in vivo sup(99m)Tc-labelled red blood cells is a technically simple, non-invasive method which allows simultaneous bilateral visualization of the pelvis, deep femoral and crural veins up to 24 hours after the labelling. The radiation dose is significantly lower than with X-ray phlebography and thus angioscintigraphy may be used repeatedly and if urgent during pregnancy. In a 'blind' study involving the results from three hospitals, angioscintigraphy correctly classified about 80% of patients with clinical signs of deep vein thrombosis (D.V.T.) when a modern gamma camera was used; inferior results were obtained with an older type of gamma camera. The results also showed that a normal angioscintigram with very high probability excludes the presence of D.V.T. but an abnormal scintigram is not specific for D.V.T. Thus the rather unpleasant conventional phlebography can be omitted in patients with normal angioscintigraphy and angioscintigraphy should be used as first choice. (U.K.)

  3. Microfluidic microarray systems and methods thereof

    Science.gov (United States)

    West, Jay A. A.; Hukari, Kyle W.; Hux, Gary A.

    2009-04-28

    Disclosed are systems that include a manifold in fluid communication with a microfluidic chip having a microarray, an illuminator, and a detector in optical communication with the microarray. Methods for using these systems for biological detection are also disclosed.

  4. Microfluidic Analytical Separator for Proteomics Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is a microfluidic device designed to effect a 2-dimensional resolution of a mixture of proteins based on isoelectric point (pI) and...

  5. Microfluidic Analytical Separator for Proteomics Project

    Data.gov (United States)

    National Aeronautics and Space Administration — SHOT proposes an innovative microfluidic device designed to effect a 2-dimensional resolution of a mixture of proteins based on isoelectric point (pI) and molecular...

  6. Migration distance-based platelet function analysis in a microfluidic system

    OpenAIRE

    Song, Suk-Heung; Lim, Chae-Seung; Shin, Sehyun

    2013-01-01

    Aggregation and adhesion of platelets to the vascular wall are shear-dependent processes that play critical roles in hemostasis and thrombosis at vascular injury sites. In this study, we designed a simple and rapid assay of platelet aggregation and adhesion in a microfluidic system. A shearing mechanism using a rotating stirrer provided adjustable shear rate and shearing time and induced platelet activation. When sheared blood was driven through the microchannel under vacuum pressure, shear-a...

  7. Microfluidic Screening of Electric Fields for Electroporation

    OpenAIRE

    Garcia, Paulo A.; Zhifei Ge; Jeffrey L. Moran; Buie, Cullen R

    2016-01-01

    Electroporation is commonly used to deliver molecules such as drugs, proteins, and/or DNA into cells, but the mechanism remains poorly understood. In this work a rapid microfluidic assay was developed to determine the critical electric field threshold required for inducing bacterial electroporation. The microfluidic device was designed to have a bilaterally converging channel to amplify the electric field to magnitudes sufficient to induce electroporation. The bacterial cells are introduced i...

  8. Molecular Imaging Probe Development using Microfluidics

    OpenAIRE

    Liu, Kan; Wang, Ming-Wei; Lin, Wei-Yu; Phung, Duy Linh; Girgis, Mark D.; Anna M. Wu; James S. Tomlinson; Shen, Clifton K.-F.

    2011-01-01

    In this manuscript, we review the latest advancement of microfluidics in molecular imaging probe development. Due to increasing needs for medical imaging, high demand for many types of molecular imaging probes will have to be met by exploiting novel chemistry/radiochemistry and engineering technologies to improve the production and development of suitable probes. The microfluidic-based probe synthesis is currently attracting a great deal of interest because of their potential to deliver many ...

  9. A Microfluidic D-subminiature Connector

    OpenAIRE

    Scott, Adina; Au, Anthony K.; Vinckenbosch, Elise; Folch, Albert

    2013-01-01

    Standardized, affordable, user-friendly world-to-chip interfaces represent one of the major barriers to the adoption of microfluidics. We present a connector system for plug-and-play interfacing of microfluidic devices to multiple input and output lines. The male connectors are based on existing standardized housings from electronics that are inexpensive and widely available. The female connectors are fabricated using familiar replica molding techniques that can easily be adopted by microflui...

  10. Microfluidics for investigating single-cell biodynamics

    OpenAIRE

    Cookson, Scott Warren

    2008-01-01

    Progress in synthetic biology requires the development of novel techniques for investigating long-term dynamics in single cells. Here, we demonstrate the utility of microfluidics for investigating single-cell biodynamics within tightly-controlled environments in the model organisms Saccharomyces cerevisiae and Escherichia coli. First, we develop a microfluidic chemostat for monitoring single-cell gene expression within large populations of S. cerevisiae over many cellular generations. We over...

  11. Integrated microfluidic device for droplet manipulation

    OpenAIRE

    Basova, E.

    2013-01-01

    Droplets based microfluidic systems have a big potential for the miniaturization of processes for bioanalysis. In the form of droplets, reagents are used in discrete volume, enabling high-throughput chemical reactions as well as single-cell encapsulation. Microreactors of this type can be manipulated and applied in bio-testing. In this work we present a platform for droplet generation and manipulation by using dielectrophoresis force. This platform is an integrated microfluidic device wit...

  12. INTEGRATED MICROFLUIDIC DEVICE FOR DROPLET MANIPULATION

    OpenAIRE

    Basova Evgenia; Drs Jakub; Zemanek Jiri; Hurak Zdenek; Foret František

    2013-01-01

    Droplets based microfluidic systems have a big potential for the miniaturization of processes for bioanalysis. In the form of droplets, reagents are used in discrete volume, enabling high-throughput chemical reactions as well as single-cell encapsulation. Microreactors of this type can be manipulated and applied in bio-testing. In this work we present a platform for droplet generation and manipulation by using dielectrophoresis force. This platform is an integrated microfluidic device wit...

  13. Microfluidics for High School Chemistry Students

    OpenAIRE

    Hemling, Melissa; Crooks, John A.; Oliver, Piercen M.; Brenner, Katie; Gilbertson, Jennifer; Lisensky, George C.; Weibel, Douglas B.

    2014-01-01

    We present a laboratory experiment that introduces high school chemistry students to microfluidics while teaching fundamental properties of acid–base chemistry. The procedure enables students to create microfluidic systems using nonspecialized equipment that is available in high school classrooms and reagents that are safe, inexpensive, and commercially available. The experiment is designed to ignite creativity and confidence about experimental design in a high school chemistry class. This ex...

  14. Uniform yeast cell assembly via microfluidics

    OpenAIRE

    Chang, Ya-Wen; He, Peng; Marquez, Samantha M.; Cheng, Zhengdong

    2012-01-01

    This paper reports the use of microfluidic approaches for the fabrication of yeastosomes (yeast-celloidosomes) based on self-assembly of yeast cells onto liquid-solid or liquid-gas interfaces. Precise control over fluidic flows in droplet- and bubble-forming microfluidic devices allows production of monodispersed, size-selected templates. The general strategy to organize and assemble living cells is to tune electrostatic attractions between the template (gel or gas core) and the cells via sur...

  15. Piezoactuators for Microfluidics : Towards Dynamic Arraying

    OpenAIRE

    Lilliehorn, Tobias

    2003-01-01

    Microfluidics can be used to increase performance, reduce reagent consumption and increase throughput in chemical analysis. With the forthcoming development of more advanced microfluidic systems, the integration of actuating elements becomes essential, giving the ability to control and manipulate fluid flow as well as sample or other components. This thesis addresses miniaturisation of piezoceramic actuators, in particular important technological issues when actuators are integrated in microf...

  16. Piramal Diagnostics

    OpenAIRE

    Neeraj Dwivedi; Arvinder Singh

    2011-01-01

    The case presents a decision situation facing the Vice President of strategic planning at Piramal Diagnostics Limited, who has to formulate the future growth strategy and decide on the roadmap. The company is the largest player in the organized medical diagnostics industry in India and has shown attractive growth in the past few years. The case describes the structural characteristics of the medical diagnostics industry in India and follows it with a description of the strengths and weaknesse...

  17. Diagnostic value of serum procalcitonin levels in children with meningitis: a comparison with blood leukocyte count and C-reactive protein

    International Nuclear Information System (INIS)

    Objectives: To determine the level of serum procalcitonin, blood leukocyte count (TLC) and C-reactive protein (CRP) in children with bacterial and non bacterial meningitis and document their efficacy in differential diagnosis. Also described are procalcitonin levels variation during treatment. Methods: From March 2005 to February 2008, we evaluated 38 clinically suspected meningitis patients in the paediatric departments, Al-Jedaany Hospital, Jeddah, KSA, for Serum procalcitonin, CRP, TLC and Lumbar punctures and CSF analysis. Patients were classified into bacterial meningitis group I (18) and non bacterial meningitis group II (20). Results: Serum PCT levels were significantly higher in bacterial meningitis (BM) 9 mean 4.8 +- 3.85 ng/ml (2.9-11.6)) compared with non bacterial meningitis (NBM) (mean 0.38 +- 0.25 ng/ml(0.31-0.61)) P< 0.001). Mean of all CSF parameters, TLC (15,000 +- 2,900 cell/ml(BM) and 9,500 +-1,105 cell/ml(NBM))and CRP (20 +- 6.8 mg/l (BM) and 12.5 +-12.0 mg/l(NBM))showed a zone of overlapping between the two groups. There is a positive correlation between serum PCT, TLC and CRP in bacterial and non bacterial meningitis cases but this relation becomes highly significant with bacterial meningitis positive group. Day 3 and day 6 treatment serum PCT was less than on admission levels (P<0.001). Conclusion: PCT can be used in the early diagnosis of bacterial meningitis and may be a useful adjunct in differentiating bacterial and non bacterial meningitis than CRP or TLC and diminishing the value of lumbar puncture performed 48-72 hours after admission to assess treatment efficacy. (author)

  18. Studies of cerebral blood flow and metabolism in patients with senile dementia of the Alzheimer's type and diagnostic evaluation of the dementing illnesses by positron emission tomography

    International Nuclear Information System (INIS)

    This study was designed to determine cerebral dysfunction in senile dementia of the Alzheimer's type (SDAT). Regional cerebral blood flow (rCBF), oxygen extraction fraction and cerebral oxygen consumption (rCMRO2) were studied in SDAT patients (n=16) and age-matched normal elderly people (n=5) by positron emission tomography (PET) using the O-15 labeled CO2 and O2 inhalation technique. The SDAT group had a significantly lower values in both rCBF and rCMRO2 than the normal control. During the early stage of SDAT, rCMRO2 was restricted to the temporal cortex; and it extended to the parietal and frontal cortices associated with a decreased rCBF as the disease progressed. Posterior temporal and posterior parietal association cortices were considered to be the most damageable part during the early stage. Bilateral differences in oxygen metabolism of the temporal and parietal cortices tended to be in accordance with clinical symptoms for disturbed speech and visuospatial function, suggesting the correlation between rCMRO2 and rCBF in SDAT. Findings of PET in SDAT differed from those obtained in each patient with multi-infarct dementia or Pick disease, in that both rCBF and rCMRO2 were inhomogeneously decreased over the whole cerebral cortex for multi-infarct dementia and in that homogeneously decreased rCBF and rCMRO2 were restricted to the frontal and temporal cortices for Pick disease. PET may have a potential for differentiating various types of dementia. (N.K.)

  19. Microfluidic Devices in Advanced Caenorhabditis elegans Research

    Directory of Open Access Journals (Sweden)

    Muniesh Muthaiyan Shanmugam

    2016-08-01

    Full Text Available The study of model organisms is very important in view of their potential for application to human therapeutic uses. One such model organism is the nematode worm, Caenorhabditis elegans. As a nematode, C. elegans have ~65% similarity with human disease genes and, therefore, studies on C. elegans can be translated to human, as well as, C. elegans can be used in the study of different types of parasitic worms that infect other living organisms. In the past decade, many efforts have been undertaken to establish interdisciplinary research collaborations between biologists, physicists and engineers in order to develop microfluidic devices to study the biology of C. elegans. Microfluidic devices with the power to manipulate and detect bio-samples, regents or biomolecules in micro-scale environments can well fulfill the requirement to handle worms under proper laboratory conditions, thereby significantly increasing research productivity and knowledge. The recent development of different kinds of microfluidic devices with ultra-high throughput platforms has enabled researchers to carry out worm population studies. Microfluidic devices primarily comprises of chambers, channels and valves, wherein worms can be cultured, immobilized, imaged, etc. Microfluidic devices have been adapted to study various worm behaviors, including that deepen our understanding of neuromuscular connectivity and functions. This review will provide a clear account of the vital involvement of microfluidic devices in worm biology.

  20. Microfluidic Devices in Advanced Caenorhabditis elegans Research.

    Science.gov (United States)

    Muthaiyan Shanmugam, Muniesh; Subhra Santra, Tuhin

    2016-01-01

    The study of model organisms is very important in view of their potential for application to human therapeutic uses. One such model organism is the nematode worm, Caenorhabditis elegans. As a nematode, C. elegans have ~65% similarity with human disease genes and, therefore, studies on C. elegans can be translated to human, as well as, C. elegans can be used in the study of different types of parasitic worms that infect other living organisms. In the past decade, many efforts have been undertaken to establish interdisciplinary research collaborations between biologists, physicists and engineers in order to develop microfluidic devices to study the biology of C. elegans. Microfluidic devices with the power to manipulate and detect bio-samples, regents or biomolecules in micro-scale environments can well fulfill the requirement to handle worms under proper laboratory conditions, thereby significantly increasing research productivity and knowledge. The recent development of different kinds of microfluidic devices with ultra-high throughput platforms has enabled researchers to carry out worm population studies. Microfluidic devices primarily comprises of chambers, channels and valves, wherein worms can be cultured, immobilized, imaged, etc. Microfluidic devices have been adapted to study various worm behaviors, including that deepen our understanding of neuromuscular connectivity and functions. This review will provide a clear account of the vital involvement of microfluidic devices in worm biology. PMID:27490525

  1. Microfluidic control of axonal guidance

    Science.gov (United States)

    Gu, Ling; Black, Bryan; Ordonez, Simon; Mondal, Argha; Jain, Ankur; Mohanty, Samarendra

    2014-10-01

    The precision of axonal pathfinding and the accurate formation of functional neural circuitry are crucial for an organism during development as well as during adult central and peripheral nerve regeneration. While chemical cues are believed to be primarily responsible for axonal pathfinding, we hypothesize that forces due to localized fluid flow may directly affect neuronal guidance during early organ development. Here, we report direct evidence of fluid flow influencing axonal migration, producing turning angles of up to 90°. Microfluidic flow simulations indicate that an axon may experience significant bending force due to cross-flow, which may contribute to the observed axonal turning. This method of flow-based guidance was successfully used to fasciculate one advancing axon onto another, showcasing the potential of this technique to be used for the formation of in vitro neuronal circuits.

  2. Microfluidic Sample Preparation for Immunoassays

    Energy Technology Data Exchange (ETDEWEB)

    Visuri, S; Benett, W; Bettencourt, K; Chang, J; Fisher, K; Hamilton, J; Krulevitch, P; Park, C; Stockton, C; Tarte, L; Wang, A; Wilson, T

    2001-08-09

    Researchers at Lawrence Livermore National Laboratory are developing means to collect and identify fluid-based biological pathogens in the forms of proteins, viruses, and bacteria. to support detection instruments, they are developing a flexible fluidic sample preparation unit. The overall goal of this Microfluidic Module is to input a fluid sample, containing background particulates and potentially target compounds, and deliver a processed sample for detection. They are developing techniques for sample purification, mixing, and filtration that would be useful to many applications including immunologic and nucleic acid assays. Many of these fluidic functions are accomplished with acoustic radiation pressure or dielectrophoresis. They are integrating these technologies into packaged systems with pumps and valves to control fluid flow through the fluidic circuit.

  3. Bistable diverter valve in microfluidics

    Science.gov (United States)

    Tesař, V.; Bandalusena, H. C. H.

    2011-05-01

    Bistable diverter valves are useful for a large number of no-moving-part flow control applications, and there is a considerable interest in using them also in microfluidics, especially for handling small pressure-driven flows. However, with decreasing Reynolds number, the Coanda effect—on which the flow diverting effect depends—becomes less effective. Authors performed a study, involving flow visualisation, PIV experiments, measurements of the flow rates, and numerical flowfield computations, aimed at clarifying behaviour of a typical fluidic valve at low Reynolds numbers. A typical fluidic valve originally developed for high Re operation was demonstrated to be useful, though with progressively limited efficiency, down to surprisingly low Re values as small as Re = 800. Also observed was a previously not reported discontinuation in the otherwise monotonic decrease in performance at Re between 1,500 and 2,000.

  4. Microthermoforming of microfluidic substrates by soft lithography (µTSL): optimization using design of experiments

    International Nuclear Information System (INIS)

    We present a detailed analysis of microthermoforming by soft lithography (µTSL) for replication of foil-based microfluidic substrates. The process was systematically optimized by design of experiments (DOE) enabling fabrication of defect-free lab-on-a-chip devices. After the assessment of typical error patterns we optimized the process toward the minimum deviation between mold and thermoformed foil substrates. The following process parameters have most significant impact on the dimensional responses (p 40% relative impact. The DOE results in an empirical process model with a maximum deviation between the prediction and experimental proof of 2% for the optimum parameter set. Finally, process optimization is validated by the fabrication and testing of a microfluidic structure for blood plasma separation from human whole blood. The optimized process enabled metering of a nominal volume of 4.0 µl of blood plasma with an accuracy deviation of 3% and a metering precision of ±7.0%. The µTSL process takes about 30 min and easily enables the replication of 300 µm wide microchannels having vertical sidewalls without any draft angles in a well-controllable way. It proves to be suitable for multiple applications in the field of microfluidic devices.

  5. Microfluidic cartridges for DNA purification and genotyping processed in standard laboratory instruments

    Science.gov (United States)

    Focke, Maximilian; Mark, Daniel; Stumpf, Fabian; Müller, Martina; Roth, Günter; Zengerle, Roland; von Stetten, Felix

    2011-06-01

    Two microfluidic cartridges intended for upgrading standard laboratory instruments with automated liquid handling capability by use of centrifugal forces are presented. The first microfluidic cartridge enables purification of DNA from human whole blood and is operated in a standard laboratory centrifuge. The second microfluidic catridge enables genotyping of pathogens by geometrically multiplexed real-time PCR. It is operated in a slightly modified off-the-shelf thermal cycler. Both solutions aim at smart and cost-efficient ways to automate work flows in laboratories. The DNA purification cartridge automates all liquid handling steps starting from a lysed blood sample to PCR ready DNA. The cartridge contains two manually crushable glass ampoules with liquid reagents. The DNA yield extracted from a 32 μl blood sample is 192 +/- 30 ng which corresponds to 53 +/- 8% of a reference extraction. The genotyping cartridge is applied to analyse isolates of the multi-resistant Staphyloccus aureus (MRSA) by real-time PCR. The wells contain pre-stored dry reagents such as primers and probes. Evaluation of the system with 44 genotyping assays showed a 100% specificity and agreement with the reference assays in standard tubes. The lower limit of detection was well below 10 copies of DNA per reaction.

  6. Transport Mechanisms of Circulating Tumor Cells in Microfluidic Devices

    Science.gov (United States)

    Rangharajan, Kaushik; Conlisk, A. T.; Prakash, Shaurya

    2014-11-01

    Lab-on-a-chip (LoC) devices are becoming an essential tool for several emerging point-of-care healthcare needs and applications. Among the plethora of challenging problems in the personalized healthcare domain, early detection of cancer continues to be a challenge. For instance, identification of most tumors occurs by the time the tumor comprises approximately 1 billion cells, with poor prognosis for metastatic disease. The key obstacle in identifying and subsequent capture of circulating tumor cells (CTCs) is that the amount of CTCs in the blood stream is ~1 in 109 cells. The fundamental challenge in design and fabrication of microfluidic devices arises due to lack of information on suitable sorting needed for sample preparation before any labeling or capture scheme can be employed. Moreover, the ability to study these low concentration cells relies on knowledge of their physical and chemical properties, of which the physical properties are poorly understood. Also, nearly all existing microfluidic mixers were developed for aqueous electrolyte solutions to enhance mixing in traditional low Re flows. However, no systematic studies have developed design rules for particle mixing. Therefore, we present a numerical model to discuss design rules for microscale mixers and sorters for particle sorting for high efficiency antibody labeling of CTCs along with presenting a pathway for a device to capture CTCs without the need for labeling based on particle electrical properties. NSF Nanoscale Science and Engineering Center (NSEC) for the Affordable Nanoengineering of Polymeric Biomedical Devices EEC-0914790.

  7. Capture of DNA in microfluidic channel using magnetic beads: increasing capture efficiency with integrated microfluidic mixer

    DEFF Research Database (Denmark)

    Lund-Olesen, Torsten; Dufva, Hans Martin; Hansen, Mikkel Fougt

    2007-01-01

    We have studied the hybridization of target DNA in solution with probe DNA on magnetic beads immobilized on the channel sidewalls in a magnetic bead separator. The hybridization is carried out under a liquid flow and is diffusion limited. Two systems are compared: one with a straight microfluidic...... place on the surface in a microfluidic system....

  8. ESTUDIO DIAGNÓSTICO DEL CLIMA LABORAL EN LA EMPRESA DE SUEROS Y PRODUCTOS HEMODERIVADOS / DIAGNOSTIC STUDY OF ORGANIZATIONAL ENVIRONMENT IN THE ENTERPRISE OF SERA AND BLOOD PRODUCTS

    Directory of Open Access Journals (Sweden)

    Yoanys Paule-Hernández

    2011-03-01

    Full Text Available

    El objetivo del presente trabajo es determinar las variables que inciden negativamente sobre la percepción que tienen las personas acerca de la calidad del trabajo que realizan y la actitud que asumen al respecto, en la Empresa de Sueros y Hemoderivados. Se evalúa el estado del clima socio-psicológico mediante el cuestionario OLARIS, con escala de 78 ítems, dividida en cinco variables y 19 subvariables; y el cuestionario autodiagnóstico sobre estilos de dirección, realizado a los jefes directos por áreas, que permite determinar su orientación como: analizador, controlador, apoyador, promocionador. Para ello se utilizó una muestra de 73 trabajadores, pertenecientes a todas las áreas de la planta, especificándose un 99,5% de confianza. En el trabajo se estableció la existencia de un estado del clima favorable, aunque también se reflejan las insatisfacciones con el propio desempeño del trabajo y del Centro, así como la percepción de un inadecuado funcionamiento de la organización, que entorpecen un mejor estado del mismo.

    Abstract

    The aim of this paper is to identify the variables that have a negative impact in people´s perception about the quality of their work and the attitude they assume in this regard at the enterprise of sera and blood products. To assess the state of socio-psychological environment it is applied the questionnaire OLARIS which has a scale of 78 items divided into five variables and 19 sub-variables, and the questionnaire of self-management style to direct supervisors from different areas in order to evaluate the management styles, such as: analyzer, supervisor, supporter, promotioner. It was selected a sample with 73 workers from all areas at the plant, with a 99.5% of confidence. As a result of this work it is shown that the state of socio-psychological environment is conducive to performance, however, also it reflected a number of dissatisfactions with the proper

  9. System-level network simulation for robust centrifugal-microfluidic lab-on-a-chip systems.

    Science.gov (United States)

    Schwarz, I; Zehnle, S; Hutzenlaub, T; Zengerle, R; Paust, N

    2016-05-10

    Centrifugal microfluidics shows a clear trend towards a higher degree of integration and parallelization. This trend leads to an increase in the number and density of integrated microfluidic unit operations. The fact that all unit operations are processed by the same common spin protocol turns higher integration into higher complexity. To allow for efficient development anyhow, we introduce advanced lumped models for network simulations in centrifugal microfluidics. These models consider the interplay of centrifugal and Euler pressures, viscous dissipation, capillary pressures and pneumatic pressures. The simulations are fast and simple to set up and allow for the precise prediction of flow rates as well as switching and valving events. During development, channel and chamber geometry variations due to manufacturing tolerances can be taken into account as well as pipetting errors, variations of contact angles, compliant chamber walls and temperature variations in the processing device. As an example of considering these parameters during development, we demonstrate simulation based robustness analysis for pneumatic siphon valving in centrifugal microfluidics. Subsequently, the influence of liquid properties on pumping and valving is studied for four liquids relevant for biochemical analysis, namely, water (large surface tension), blood plasma (large contact angle hysteresis), ethanol/water (highly wetting) and glycerine/water (highly viscous). In a second example, we derive a spin protocol to attain a constant flow rate under varying pressure conditions. Both examples show excellent agreement with experimental validations. PMID:27095248

  10. Biomarkers and diagnostic tools for detection of Helicobacter pylori.

    Science.gov (United States)

    Khalilpour, Akbar; Kazemzadeh-Narbat, Mehdi; Tamayol, Ali; Oklu, Rahmi; Khademhosseini, Ali

    2016-06-01

    Helicobacter pylori is responsible for worldwide chronic bacterial infection in humans affecting approximately half of the world's population. H. pylori is associated with significant morbidity and mortality including gastric cancer. The infection has both direct and indirect impacts on economic and overall well-being of patients; hence, there is a great need for diagnostic markers that could be used in the development of diagnostic kits. Here, we briefly review general aspects of H. pylori infection and the diagnostic biomarkers used in laboratory tests today with a focus on the potential role of microfluidic systems in future immunodiagnosis platforms. PMID:27084783

  11. ITER diagnostics

    International Nuclear Information System (INIS)

    As part of the ITER Conceptual Design Activity (CDA), three workshops were held on plasma diagnostics. From these conference, a set of diagnostics for the full operation of ITER has been developed. This report summarizes the results of these design and discussion activities, and the incorporation of the concepts developed into the overall ITER experiment. Refs, figs and tabs

  12. Molecular Diagnostics

    OpenAIRE

    Choe, Hyonmin; Deirmengian, Carl A; Hickok, Noreen J.; Morrison, Tiffany N.; Tuan, Rocky S.

    2015-01-01

    Orthopaedic infections are complex conditions that require immediate diagnosis and accurate identification of the causative organisms to facilitate appropriate management. Conventional methodologies for diagnosis of these infections sometimes lack accuracy or sufficient rapidity. Current molecular diagnostics are an emerging area of bench-to-bedside research in orthopaedic infections. Examples of promising molecular diagnostics include measurement of a specific biomarker in the synovial fluid...

  13. Diagnostic dilemma

    DEFF Research Database (Denmark)

    Feldt-Rasmussen, Ulla; Dobrovolny, Robert; Nazarenko, Irina;

    2011-01-01

    in two expert laboratories did not identify a confirmatory mutation, presenting a diagnostic dilemma. A renal biopsy proved diagnostic and renewed efforts to detect an a-Gal A mutation. Subsequent gene dosage analyses identified a large a-Gal A deletion confirming her heterozygosity, and she was...

  14. Ebola Check: Delivering molecular diagnostics at the point of need.

    Science.gov (United States)

    Moschos, Sterghios A

    2015-01-01

    The 2013-5 global outbreak of Ebolavirus disease brought to sharp focus the need for diagnostic capacity to be equitably available on a global scale: from the most under-developed areas of resource-limited countries in West Africa to high volume international travel hubs in Europe and the USA. Quick detection of the causal agent of disease is pivotal to containment, contact tracing and clinical action to protect healthcare workers, communities and patients. Nucleic acid testing (NAT) by real time reverse transcription quantitative polymerase chain reaction (RT-PCR) has emerged as the preferred method for reliable patient status confirmation. Presently, this is served through advanced clinical molecular laboratory testing in a developed a novel platform technology that can QUantitatively, RAPidly IDentify (QuRapID) known RNA or DNA targets in viruses, bacteria, or eukaryotic cells directly in crude biofluids, including whole blood, in under 40min using a 5 microliter sample. The portable, battery-operated system lacks microfluidics, pumps or other sensitive/high cost parts making it suitable for the environmental and economic challenges of resource-limited countries. The simple, safe, 5-step sample-to-answer process requires minimal training and informs frontline healthcare workers of diagnostic status, whilst reporting remotely epidemiologically relevant results. Data on biosafety level 2 surrogate Ebolavirus templates presented in encapsulated or enveloped viruses indicate performance comparable to clinical laboratory testing and utility beyond filoviruses. Emerging performance data on live Ebolavirus, non-human primate disease model and patient samples, as well as future development plans will be discussed. PMID:26665227

  15. From microfluidic modules to an integrated Lab-on-a-chip system for the detection of Francisella tularensis

    Science.gov (United States)

    Hlawatsch, Nadine; Krumbholz, Marco; Prüfer, Anna; Moche, Christian; Becker, Holger; Gärtner, Claudia

    2013-05-01

    Lab-on-a-chip (LoC) systems translating the whole process of pathogen analysis to an integrated, miniaturized, and automatically functioning microfluidic platform are generally expected to be very promising future diagnostic approaches. The development of such a LoC system for the detection of bacterial pathogens applied to the example pathogen Francisella tularensis is described in this report. To allow functional testing of the whole process cascade before final device integration, various bio-analytical steps such as cell lysis, DNA extraction and purification, continuous-flow PCR and analyte detection have been adapted to unique functional microfluidic modules. As a successive step, positively tested modules for pathogen detection have been successfully assembled to an integrated chip. Moreover, technical solutions for a smooth interaction between sample input from the outer world as well as microfluidic chip and chip driving instrument have been developed. In conclusion, a full repertoire of analytical tools have been developed and successfully tested in the concerted manner of a functionally integrated microfluidic device representing a tool for future diagnostic approaches.

  16. Rapid microfluidic thermal cycler for nucleic acid amplification

    Energy Technology Data Exchange (ETDEWEB)

    Beer, Neil Reginald; Vafai, Kambiz

    2015-10-27

    A system for thermal cycling a material to be thermal cycled including a microfluidic heat exchanger; a porous medium in the microfluidic heat exchanger; a microfluidic thermal cycling chamber containing the material to be thermal cycled, the microfluidic thermal cycling chamber operatively connected to the microfluidic heat exchanger; a working fluid at first temperature; a first system for transmitting the working fluid at first temperature to the microfluidic heat exchanger; a working fluid at a second temperature, a second system for transmitting the working fluid at second temperature to the microfluidic heat exchanger; a pump for flowing the working fluid at the first temperature from the first system to the microfluidic heat exchanger and through the porous medium; and flowing the working fluid at the second temperature from the second system to the heat exchanger and through the porous medium.

  17. Home Use Tests: Fecal Occult Blood

    Science.gov (United States)

    ... Procedures In Vitro Diagnostics Home Use Tests Fecal Occult Blood Share Tweet Linkedin Pin it More sharing ... test kit to measure the presence of hidden (occult) blood in your stool (feces). What is fecal ...

  18. A microfluidic paper-based electrochemical biosensor array for multiplexed detection of metabolic biomarkers

    Directory of Open Access Journals (Sweden)

    Chen Zhao, Martin M Thuo and Xinyu Liu

    2013-01-01

    Full Text Available Paper-based microfluidic devices have emerged as simple yet powerful platforms for performing low-cost analytical tests. This paper reports a microfluidic paper-based electrochemical biosensor array for multiplexed detection of physiologically relevant metabolic biomarkers. Different from existing paper-based electrochemical devices, our device includes an array of eight electrochemical sensors and utilizes a handheld custom-made electrochemical reader (potentiostat for signal readout. The biosensor array can detect several analytes in a sample solution and produce multiple measurements for each analyte from a single run. Using the device, we demonstrate simultaneous detection of glucose, lactate and uric acid in urine, with analytical performance comparable to that of the existing commercial and paper-based platforms. The paper-based biosensor array and its electrochemical reader will enable the acquisition of high-density, statistically meaningful diagnostic information at the point of care in a rapid and cost-efficient way.

  19. A microfluidic paper-based electrochemical biosensor array for multiplexed detection of metabolic biomarkers

    Science.gov (United States)

    Zhao, Chen; Thuo, Martin M.; Liu, Xinyu

    2013-10-01

    Paper-based microfluidic devices have emerged as simple yet powerful platforms for performing low-cost analytical tests. This paper reports a microfluidic paper-based electrochemical biosensor array for multiplexed detection of physiologically relevant metabolic biomarkers. Different from existing paper-based electrochemical devices, our device includes an array of eight electrochemical sensors and utilizes a handheld custom-made electrochemical reader (potentiostat) for signal readout. The biosensor array can detect several analytes in a sample solution and produce multiple measurements for each analyte from a single run. Using the device, we demonstrate simultaneous detection of glucose, lactate and uric acid in urine, with analytical performance comparable to that of the existing commercial and paper-based platforms. The paper-based biosensor array and its electrochemical reader will enable the acquisition of high-density, statistically meaningful diagnostic information at the point of care in a rapid and cost-efficient way.

  20. Microfluidic Organ/Body-on-a-Chip Devices at the Convergence of Biology and Microengineering

    Directory of Open Access Journals (Sweden)

    Ana Rubina Perestrelo

    2015-12-01

    Full Text Available Recent advances in biomedical technologies are mostly related to the convergence of biology with microengineering. For instance, microfluidic devices are now commonly found in most research centers, clinics and hospitals, contributing to more accurate studies and therapies as powerful tools for drug delivery, monitoring of specific analytes, and medical diagnostics. Most remarkably, integration of cellularized constructs within microengineered platforms has enabled the recapitulation of the physiological and pathological conditions of complex tissues and organs. The so-called “organ-on-a-chip” technology, which represents a new avenue in the field of advanced in vitro models, with the potential to revolutionize current approaches to drug screening and toxicology studies. This review aims to highlight recent advances of microfluidic-based devices towards a body-on-a-chip concept, exploring their technology and broad applications in the biomedical field.

  1. Microfluidic Surface Plasmon Resonance Sensors: From Principles to Point-of-Care Applications.

    Science.gov (United States)

    Wang, Da-Shin; Fan, Shih-Kang

    2016-01-01

    Surface plasmon resonance (SPR) is a label-free, highly-sensitive, and real-time sensing technique. Conventional SPR sensors, which involve a planar thin gold film, have been widely exploited in biosensing; various miniaturized formats have been devised for portability purposes. Another type of SPR sensor which utilizes localized SPR (LSPR), is based on metal nanostructures with surface plasmon modes at the structural interface. The resonance condition is sensitive to the refractive index change of the local medium. The principles of these two types of SPR sensors are reviewed and their integration with microfluidic platforms is described. Further applications of microfluidic SPR sensors to point-of-care (POC) diagnostics are discussed. PMID:27472340

  2. Structure and fabrication details of an integrated modularized microfluidic system

    OpenAIRE

    Qingchang Tian; Ying Mu; Yanan Xu; Qi Song; Bingwen Yu; Congcong Ma; Wei Jin; Qinhan Jin

    2015-01-01

    This article contains schemes, original experimental data and figures for an integrated modularized microfluidic system described in “An integrated microfluidic system for bovine DNA purification and digital PCR detection [1]”. In this data article, we described the structure and fabrication of the integrated modularized microfluidic system. This microfluidic system was applied to isolate DNA from ovine tissue lysate and detect the bovine DNA with digital PCR (dPCR). The DNA extraction effici...

  3. Microfluidics: an enabling technology for the life sciences

    OpenAIRE

    Zengerle, R.; Koltay, P.; Ducrée, Jens

    2004-01-01

    During the last year we have investigated existing and future markets, products and technologies for microfluidics in the life sciences. Within this paper we present some of the findings and discuss a major trend identified within this project: the development of microfluidic platforms for flexible design of application specific integrated microfluidic systems. We discuss two platforms in detail which are currently under development in our lab: microfluidics on a rotating CD ("Lab-CD") as wel...

  4. A semi-automated, field-portable microscopy platform for clinical diagnostic applications

    Science.gov (United States)

    Jagannadh, Veerendra Kalyan; Srinivasan, Rajesh; Gorthi, Sai Siva

    2015-08-01

    Clinical microscopy is a versatile diagnostic platform used for diagnosis of a multitude of diseases. In the recent past, many microfluidics based point-of-care diagnostic devices have been developed, which serve as alternatives to microscopy. However, these point-of-care devices are not as multi-functional and versatile as clinical microscopy. With the use of custom designed optics and microfluidics, we have developed a versatile microscopy-based cellular diagnostic platform, which can be used at the point of care. The microscopy platform presented here is capable of detecting infections of very low parasitemia level (in a very small quantity of sample), without the use of any additional computational hardware. Such a cost-effective and portable diagnostic device, would greatly impact the quality of health care available to people living in rural locations of the world. Apart from clinical diagnostics, it's applicability to field research in environmental microbiology has also been outlined.

  5. Controlling two-phase flow in microfluidic systems using electrowetting

    NARCIS (Netherlands)

    Gu, Hao

    2011-01-01

    Electrowetting (EW)-based digital microfluidic systems (DMF) and droplet-based two-phase flow microfluidic systems (TPF) with closed channels are the most widely used microfluidic platforms. In general, these two approaches have been considered independently. However, integrating the two technologie

  6. Dynamic Interfacial Tension Measurements with Microfluidic Y-Junctions

    OpenAIRE

    Steegmans, M.L.J.; Warmerdam, A.; Schroën, C.G.P.H.; Boom, R.M.

    2009-01-01

    Emulsification in microdevices (microfluidic emulsification) involves micrometer-sized droplets and fast interface expansion rates. In addition, droplets are formed in less than milliseconds, and therefore traditional tensiometric techniques cannot be used to quantify the actual interfacial tension. In this paper, monodisperse droplets formed at flat microfluidic Y-junctions were used to quantify the apparent dynamic interfacial tension during (microfluidic) emulsification. Hexadecane droplet...

  7. Operation placement for application-specific digital microfluidic biochips

    DEFF Research Database (Denmark)

    Alistar, Mirela; Pop, Paul; Madsen, Jan

    2013-01-01

    Microfluidic-based biochips are replacing the conventional biochemical analyzers, and are able to integrate onchip all the necessary functions for biochemical analysis using microfluidics. The digital microfluidic biochips are based on the manipulation of liquids not as a continuous flow, but as......, such that the application completion time is minimized. The proposed algorithm has been evaluated using several benchmarks....

  8. Microfluidic multiculture assay to analyze biomolecular signaling in angiogenesis.

    Science.gov (United States)

    Theberge, Ashleigh B; Yu, Jiaquan; Young, Edmond W K; Ricke, William A; Bushman, Wade; Beebe, David J

    2015-03-17

    Angiogenesis (the formation of blood vessels from existing blood vessels) plays a critical role in many diseases such as cancer, benign tumors, and macular degeneration. There is a need for cell culture methods capable of dissecting the intricate regulation of angiogenesis within the microenvironment of the vasculature. We have developed a microscale cell-based assay that responds to complex pro- and antiangiogenic soluble factors with an in vitro readout for vessel formation. The power of this system over traditional techniques is that we can incorporate the whole milieu of soluble factors produced by cells in situ into one biological readout (vessel formation), even if the identity of the factors is unknown. We have currently incorporated macrophages, endothelial cells, and fibroblasts into the assay, with the potential to include additional cell types in the future. Importantly, the microfluidic platform is simple to operate and multiplex to test drugs targeting angiogenesis in a more physiologically relevant context. As a proof of concept, we tested the effect of an enzyme inhibitor (targeting matrix metalloproteinase 12) on vessel formation; the triculture microfluidic assay enabled us to capture a dose-dependent effect entirely missed in a simplified coculture assay (p < 0.0001). This result underscores the importance of cell-based assays that capture chemical cross-talk occurring between cell types. The microscale dimensions significantly reduce cell consumption compared to conventional well plate platforms, enabling the use of limited primary cells from patients in future investigations and offering the potential to screen therapeutic approaches for individual patients in vitro. PMID:25719435

  9. Integrated Blood Barcode Chips

    OpenAIRE

    Fan, Rong; Vermesh, Ophir; Srivastava, Alok; Yen, Brian K.H.; Qin, Lidong; Ahmad, Habib; Kwong, Gabriel A.; Liu, Chao-Chao; Gould, Juliane; Hood, Leroy; Heath, James R.

    2008-01-01

    Blood comprises the largest version of the human proteome1. Changes of plasma protein profiles can reflect physiological or pathological conditions associated with many human diseases, making blood the most important fluid for clinical diagnostics2-4. Nevertheless, only a handful of plasma proteins are utilized in routine clinical tests. This is due to a host of reasons, including the intrinsic complexity of the plasma proteome1, the heterogeneity of human diseases and the fast kinetics assoc...

  10. Polymer-based platform for microfluidic systems

    Science.gov (United States)

    Benett, William; Krulevitch, Peter; Maghribi, Mariam; Hamilton, Julie; Rose, Klint; Wang, Amy W.

    2009-10-13

    A method of forming a polymer-based microfluidic system platform using network building blocks selected from a set of interconnectable network building blocks, such as wire, pins, blocks, and interconnects. The selected building blocks are interconnectably assembled and fixedly positioned in precise positions in a mold cavity of a mold frame to construct a three-dimensional model construction of a microfluidic flow path network preferably having meso-scale dimensions. A hardenable liquid, such as poly (dimethylsiloxane) is then introduced into the mold cavity and hardened to form a platform structure as well as to mold the microfluidic flow path network having channels, reservoirs and ports. Pre-fabricated elbows, T's and other joints are used to interconnect various building block elements together. After hardening the liquid the building blocks are removed from the platform structure to make available the channels, cavities and ports within the platform structure. Microdevices may be embedded within the cast polymer-based platform, or bonded to the platform structure subsequent to molding, to create an integrated microfluidic system. In this manner, the new microfluidic platform is versatile and capable of quickly generating prototype systems, and could easily be adapted to a manufacturing setting.

  11. Mechanically activated artificial cell by using microfluidics

    Science.gov (United States)

    Ho, Kenneth K. Y.; Lee, Lap Man; Liu, Allen P.

    2016-01-01

    All living organisms sense mechanical forces. Engineering mechanosensitive artificial cell through bottom-up in vitro reconstitution offers a way to understand how mixtures of macromolecules assemble and organize into a complex system that responds to forces. We use stable double emulsion droplets (aqueous/oil/aqueous) to prototype mechanosensitive artificial cells. In order to demonstrate mechanosensation in artificial cells, we develop a novel microfluidic device that is capable of trapping double emulsions into designated chambers, followed by compression and aspiration in a parallel manner. The microfluidic device is fabricated using multilayer soft lithography technology, and consists of a control layer and a deformable flow channel. Deflections of the PDMS membrane above the main microfluidic flow channels and trapping chamber array are independently regulated pneumatically by two sets of integrated microfluidic valves. We successfully compress and aspirate the double emulsions, which result in transient increase and permanent decrease in oil thickness, respectively. Finally, we demonstrate the influx of calcium ions as a response of our mechanically activated artificial cell through thinning of oil. The development of a microfluidic device to mechanically activate artificial cells creates new opportunities in force-activated synthetic biology. PMID:27610921

  12. Valve Concepts for Microfluidic Cell Handling

    Directory of Open Access Journals (Sweden)

    M. Grabowski

    2010-01-01

    Full Text Available In this paper we present various pneumatically actuated microfluidic valves to enable user-defined fluid management within a microfluidic chip. To identify a feasible valve design, certain valve concepts are simulated in ANSYS to investigate the pressure dependent opening and closing characteristics of each design. The results are verified in a series of tests. Both the microfluidic layer and the pneumatic layer are realized by means of soft-lithographic techniques. In this way, a network of channels is fabricated in photoresist as a molding master. By casting these masters with PDMS (polydimethylsiloxane we get polymeric replicas containing the channel network. After a plasma-enhanced bonding process, the two layers are irreversibly bonded to each other. The bonding is tight for pressures up to 2 bar. The valves are integrated into a microfluidic cell handling system that is designed to manipulate cells in the presence of a liquid reagent (e.g. PEG – polyethylene glycol, for cell fusion. For this purpose a user-defined fluid management system is developed. The first test series with human cell lines show that the microfluidic chip is suitable for accumulating cells within a reaction chamber, where they can be flushed by a liquid medium.

  13. Microfluidic CODES: a scalable multiplexed electronic sensor for orthogonal detection of particles in microfluidic channels.

    Science.gov (United States)

    Liu, Ruxiu; Wang, Ningquan; Kamili, Farhan; Sarioglu, A Fatih

    2016-04-12

    Numerous biophysical and biochemical assays rely on spatial manipulation of particles/cells as they are processed on lab-on-a-chip devices. Analysis of spatially distributed particles on these devices typically requires microscopy negating the cost and size advantages of microfluidic assays. In this paper, we introduce a scalable electronic sensor technology, called microfluidic CODES, that utilizes resistive pulse sensing to orthogonally detect particles in multiple microfluidic channels from a single electrical output. Combining the techniques from telecommunications and microfluidics, we route three coplanar electrodes on a glass substrate to create multiple Coulter counters producing distinct orthogonal digital codes when they detect particles. We specifically design a digital code set using the mathematical principles of Code Division Multiple Access (CDMA) telecommunication networks and can decode signals from different microfluidic channels with >90% accuracy through computation even if these signals overlap. As a proof of principle, we use this technology to detect human ovarian cancer cells in four different microfluidic channels fabricated using soft lithography. Microfluidic CODES offers a simple, all-electronic interface that is well suited to create integrated, low-cost lab-on-a-chip devices for cell- or particle-based assays in resource-limited settings. PMID:27021807

  14. Diagnostic Imaging

    Science.gov (United States)

    Diagnostic imaging lets doctors look inside your body for clues about a medical condition. A variety of machines and ... and activities inside your body. The type of imaging your doctor uses depends on your symptoms and ...

  15. Migration distance-based platelet function analysis in a microfluidic system.

    Science.gov (United States)

    Song, Suk-Heung; Lim, Chae-Seung; Shin, Sehyun

    2013-01-01

    Aggregation and adhesion of platelets to the vascular wall are shear-dependent processes that play critical roles in hemostasis and thrombosis at vascular injury sites. In this study, we designed a simple and rapid assay of platelet aggregation and adhesion in a microfluidic system. A shearing mechanism using a rotating stirrer provided adjustable shear rate and shearing time and induced platelet activation. When sheared blood was driven through the microchannel under vacuum pressure, shear-activated platelets adhered to a collagen-coated surface, causing blood flow to significantly slow and eventually stop. To measure platelet adhesion and aggregation, the migration distance (MD) of blood through the microchannel was monitored. As the microstirrer speed increased, MD initially decreased exponentially but then increased beyond a critical rpm. For platelet-excluded blood samples, there were no changes in MD with increasing stirrer speed. These findings imply that the stirrer provided sufficiently high shear to activate platelets and that blood MD is a potentially valuable index for measuring the shear-dependence of platelet activation. Our microfluidic system is quick and simple, while providing a precise assay to measure the effects of shear on platelet aggregation and adhesion. PMID:24396535

  16. Droplet Microfluidics for Virus Discovery

    Science.gov (United States)

    Rotem, Assaf; Cockrell, Shelley; Guo, Mira; Pipas, James; Weitz, David

    2012-02-01

    The ability to detect, isolate, and characterize an infectious agent is important for diagnosing and curing infectious diseases. Detecting new viral diseases is a challenge because the number of virus particles is often low and/or localized to a small subset of cells. Even if a new virus is detected, it is difficult to isolate it from clinical or environmental samples where multiple viruses are present each with very different properties. Isolation is crucial for whole genome sequencing because reconstructing a genome from fragments of many different genomes is practically impossible. We present a Droplet Microfluidics platform that can detect, isolate and sequence single viral genomes from complex samples containing mixtures of many viruses. We use metagenomic information about the sample of mixed viruses to select a short genomic sequence whose genome we are interested in characterizing. We then encapsulate single virions from the same sample in picoliter volume droplets and screen for successful PCR amplification of the sequence of interest. The selected drops are pooled and their contents sequenced to reconstruct the genome of interest. This method provides a general tool for detecting, isolating and sequencing genetic elements in clinical and environmental samples.

  17. Microfluidics of soft granular gels

    Science.gov (United States)

    Nixon, Ryan; Bhattacharjee, Tapomoy; Sawyer, W. Gregory; Angelini, Thomas E.

    Microfluidic methods for encapsulating cells and particles typically involve drop making with two immiscible fluids. The main materials constraint in this approach is surface tension, creating inherent instability between the two fluids. We can eliminate this instability by using miscible inner and outer phases. This is achieved by using granular micro gels which are chemically miscible but physically do not mix. These microgels are yield stress materials, so they flow as solid plugs far from shear gradients, and fluidize where gradients are generated - near an injection nozzle for example. We have found that tuning the yield stress of the material by varying polymer concentration, device performance can be controlled. The solid like behavior of the gel allows us to produces infinitely stable jets that maintain their integrity and configuration over long distances and times. These properties can be combined and manipulated to produce discrete particulate bunches of an inner phase, flowing inside of an outer phase, well enough even to print a Morse code message suspended within flow chambers about a millimeter in diameter moving at millimeters a second.

  18. A fully integrated microfluidic genetic analysis system with sample-in-answer-out capability.

    Science.gov (United States)

    Easley, Christopher J; Karlinsey, James M; Bienvenue, Joan M; Legendre, Lindsay A; Roper, Michael G; Feldman, Sanford H; Hughes, Molly A; Hewlett, Erik L; Merkel, Tod J; Ferrance, Jerome P; Landers, James P

    2006-12-19

    We describe a microfluidic genetic analysis system that represents a previously undescribed integrated microfluidic device capable of accepting whole blood as a crude biological sample with the endpoint generation of a genetic profile. Upon loading the sample, the glass microfluidic genetic analysis system device carries out on-chip DNA purification and PCR-based amplification, followed by separation and detection in a manner that allows for microliter samples to be screened for infectious pathogens with sample-in-answer-out results in pump delivers sample/reagents to the chip for nucleic acid purification from a biological sample. Elastomeric membrane valving isolates each distinct functional region of the device and, together with resistive flow, directs purified DNA and PCR reagents from the extraction domain into a 550-nl chamber for rapid target sequence PCR amplification. Repeated pressure-based injections of nanoliter aliquots of amplicon (along with the DNA sizing standard) allow electrophoretic separation and detection to provide DNA fragment size information. The presence of Bacillus anthracis (anthrax) in 750 nl of whole blood from living asymptomatic infected mice and of Bordetella pertussis in 1 microl of nasal aspirate from a patient suspected of having whooping cough are confirmed by the resultant genetic profile. PMID:17159153

  19. Microfluidic Multichannel Flow Cytometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Techshot, Inc. proposes continued research and development of an on-orbit cell counter culminating in a deliverable hand-held blood cell counter in the form of a...

  20. Microfluidic isolation and transcriptome analysis of serum microvesicles.

    Science.gov (United States)

    Chen, Chihchen; Skog, Johan; Hsu, Chia-Hsien; Lessard, Ryan T; Balaj, Leonora; Wurdinger, Thomas; Carter, Bob S; Breakefield, Xandra O; Toner, Mehmet; Irimia, Daniel

    2010-02-21

    Microvesicles (exosomes) shed from both normal and cancerous cells may serve as means of intercellular communication. These microvesicles carry proteins, lipids and nucleic acids derived from the host cell. Their isolation and analysis from blood samples have the potential to provide information about state and progression of malignancy and should prove of great clinical importance as biomarkers for a variety of disease states. However, current protocols for isolation of microvesicles from blood require high-speed centrifugation and filtration, which are cumbersome and time consuming. In order to take full advantage of the potential of microvesicles as biomarkers for clinical applications, faster and simpler methods of isolation will be needed. In this paper, we present an easy and rapid microfluidic immunoaffinity method to isolate microvesicles from small volumes of both serum from blood samples and conditioned medium from cells in culture. RNA of high quality can be extracted from these microvesicles providing a source of information about the genetic status of tumors to serve as biomarkers for diagnosis and prognosis of cancer. PMID:20126692

  1. Microfluidic isolation and transcriptome analysis of serum microvesicles†

    Science.gov (United States)

    Chen, Chihchen; Skog, Johan; Hsu, Chia-Hsien; Lessard, Ryan T.; Balaj, Leonora; Wurdinger, Thomas; Carter, Bob S.; Breakefield, Xandra O.; Toner, Mehmet

    2010-01-01

    Microvesicles (exosomes) shed from both normal and cancerous cells may serve as means of intercellular communication. These microvesicles carry proteins, lipids and nucleic acids derived from the host cell. Their isolation and analysis from blood samples have the potential to provide information about state and progression of malignancy and should prove of great clinical importance as biomarkers for a variety of disease states. However, current protocols for isolation of microvesicles from blood require high-speed centrifugation and filtration, which are cumbersome and time consuming. In order to take full advantage of the potential of microvesicles as biomarkers for clinical applications, faster and simpler methods of isolation will be needed. In this paper, we present an easy and rapid microfluidic immunoaffinity method to isolate microvesicles from small volumes of both serum from blood samples and conditioned medium from cells in culture. RNA of high quality can be extracted from these microvesicles providing a source of information about the genetic status of tumors to serve as biomarkers for diagnosis and prognosis of cancer. PMID:20126692

  2. Temperature Sensing in Modular Microfluidic Architectures

    Directory of Open Access Journals (Sweden)

    Krisna C. Bhargava

    2016-01-01

    Full Text Available A discrete microfluidic element with integrated thermal sensor was fabricated and demonstrated as an effective probe for process monitoring and prototyping. Elements were constructed using stereolithography and market-available glass-bodied thermistors within the modular, standardized framework of previous discrete microfluidic elements demonstrated in the literature. Flow rate-dependent response due to sensor self-heating and microchannel heating and cooling was characterized and shown to be linear in typical laboratory conditions. An acid-base neutralization reaction was performed in a continuous flow setting to demonstrate applicability in process management: the ratio of solution flow rates was varied to locate the equivalence point in a titration, closely matching expected results. This element potentially enables complex, three-dimensional microfluidic architectures with real-time temperature feedback and flow rate sensing, without application specificity or restriction to planar channel routing formats.

  3. Uniform yeast cell assembly via microfluidics.

    Science.gov (United States)

    Chang, Ya-Wen; He, Peng; Marquez, Samantha M; Cheng, Zhengdong

    2012-06-01

    This paper reports the use of microfluidic approaches for the fabrication of yeastosomes (yeast-celloidosomes) based on self-assembly of yeast cells onto liquid-solid or liquid-gas interfaces. Precise control over fluidic flows in droplet- and bubble-forming microfluidic devices allows production of monodispersed, size-selected templates. The general strategy to organize and assemble living cells is to tune electrostatic attractions between the template (gel or gas core) and the cells via surface charging. Layer-by-Layer (LbL) polyelectrolyte deposition was employed to invert or enhance charges of solid surfaces. We demonstrated the ability to produce high-quality, monolayer-shelled yeastosome structures under proper conditions when sufficient electrostatic driving forces are present. The combination of microfluidic fabrication with cell self-assembly enables a versatile platform for designing synthetic hierarchy bio-structures. PMID:22655026

  4. A microfluidic toolbox approach to CBRNE sensing

    Science.gov (United States)

    Gärtner, Claudia; Klemm, Richard; Hlawatsch, Nadine; Becker, Holger

    2012-06-01

    Microfluidics has proven to be a very effective technology for the identification of biological and chemical analytes in a CBRNE scenario. As it will be shown in the following, the required steps of those analytical processes are manifold making the development of an integrated microfluidic device a complicated project with a high level of technological risk, because all necessary analytical processes have to be implemented into a single device. The implementation is initiated by a dissection of the biochemical workflow into mandatory bio-analytical steps and the resulting protocol for each of those steps is translated into an appropriate design of a chip-based unit. In this report, examples for such chipbased functional modules are given. In addition, examples for a merging of positively tested modules into an integrated chip are shown and, finally, representatives for a smooth interaction between outer world, microfluidic chip, and chip driving instrument are presented.

  5. Microfluidic Pumps Containing Teflon [Trademark] AF Diaphragms

    Science.gov (United States)

    Willis, Peter; White, Victor; Grunthaner, Frank; Ikeda, Mike; Mathies, Richard A.

    2009-01-01

    Microfluidic pumps and valves based on pneumatically actuated diaphragms made of Teflon AF polymers are being developed for incorporation into laboratory-on-a-chip devices that must perform well over temperature ranges wider than those of prior diaphragm-based microfluidic pumps and valves. Other potential applications include implanted biomedical microfluidic devices, wherein the biocompatability of Teflon AF polymers would be highly advantageous. These pumps and valves have been demonstrated to function stably after cycling through temperatures from -125 to 120 C. These pumps and valves are intended to be successors to similar prior pumps and valves containing diaphragms made of polydimethylsiloxane (PDMS) [commonly known as silicone rubber]. The PDMS-containing valves ae designed to function stably only within the temperature range from 5 to 80 C. Undesirably, PDMS membranes are somwehat porous and retain water. PDMS is especially unsuitable for use at temperatures below 0 C because the formation of ice crystals increases porosity and introduces microshear.

  6. Mutation Scanning Using MUT-MAP, a High-Throughput, Microfluidic Chip-Based, Multi-Analyte Panel

    OpenAIRE

    Patel, Rajesh; Tsan, Alison; Tam, Rachel; Desai, Rupal; Schoenbrunner, Nancy; Myers, Thomas W.; Bauer, Keith; Smith, Edward; Raja, Rajiv

    2012-01-01

    Targeted anticancer therapies rely on the identification of patient subgroups most likely to respond to treatment. Predictive biomarkers play a key role in patient selection, while diagnostic and prognostic biomarkers expand our understanding of tumor biology, suggest treatment combinations, and facilitate discovery of novel drug targets. We have developed a high-throughput microfluidics method for mutation detection (MUT-MAP, mutation multi-analyte panel) based on TaqMan or allele-specific P...

  7. Preparation of nanoparticles by continuous-flow microfluidics

    International Nuclear Information System (INIS)

    We review a variety of micro- and nanoparticle formulations produced with microfluidic methods. A diverse variety of approaches to generate microscale and nanoscale particles has been reported. Here we emphasize the use of microfluidics, specifically microfluidic systems that operate in a continuous flow mode, thereby allowing continuous generation of desired particle formulations. The generation of semiconductor quantum dots, metal colloids, emulsions, and liposomes is considered. To emphasize the potential benefits of the continuous-flow microfluidic methodology for nanoparticle generation, preliminary data on the size distribution of liposomes formed using the microfluidic approach is compared to the traditional bulk alcohol injection method.

  8. Optical manipulation with two beam traps in microfluidic polymer systems

    DEFF Research Database (Denmark)

    Khoury Arvelo, Maria; Matteucci, Marco; Sørensen, Kristian Tølbøl; Bilenberg, Brian; Vannahme, Christoph; Kristensen, Anders; Berg-Sørensen, Kirstine

    2015-01-01

    An optical trapping system with two opposing laser beams, also known as the optical stretcher, are naturally constructed inside a microfluidic lab-on-chip system. We present and compare two approaches to combine a simple microfluidic system with either waveguides directly written in the microflui......An optical trapping system with two opposing laser beams, also known as the optical stretcher, are naturally constructed inside a microfluidic lab-on-chip system. We present and compare two approaches to combine a simple microfluidic system with either waveguides directly written in the...... microfluidic chip or with optical fibers mounted in the chip....

  9. Packaging of silicon sensors for microfluidic bio-analytical applications

    International Nuclear Information System (INIS)

    A new industrial concept is presented for packaging biosensor chips in disposable microfluidic cartridges to enable medical diagnostic applications. The inorganic electronic substrates, such as silicon or glass, are integrated in a polymer package which provides the electrical and fluidic interconnections to the world and provides mechanical strength and protection for out-of-lab use. The demonstrated prototype consists of a molded interconnection device (MID), a silicon-based giant magneto-resistive (GMR) biosensor chip, a flex and a polymer fluidic part with integrated tubing. The various processes are compatible with mass manufacturing and run at a high yield. The devices show a reliable electrical interconnection between the sensor chip and readout electronics during extended wet operation. Sandwich immunoassays were carried out in the cartridges with surface functionalized sensor chips. Biological response curves were determined for different concentrations of parathyroid hormone (PTH) on the packaged biosensor, which demonstrates the functionality and biocompatibility of the devices. The new packaging concept provides a platform for easy further integration of electrical and fluidic functions, as for instance required for integrated molecular diagnostic devices in cost-effective mass manufacturing

  10. Burn injury reduces neutrophil directional migration speed in microfluidic devices.

    Directory of Open Access Journals (Sweden)

    Kathryn L Butler

    Full Text Available Thermal injury triggers a fulminant inflammatory cascade that heralds shock, end-organ failure, and ultimately sepsis and death. Emerging evidence points to a critical role for the innate immune system, and several studies had documented concurrent impairment in neutrophil chemotaxis with these post-burn inflammatory changes. While a few studies suggest that a link between neutrophil motility and patient mortality might exist, so far, cumbersome assays have prohibited exploration of the prognostic and diagnostic significance of chemotaxis after burn injury. To address this need, we developed a microfluidic device that is simple to operate and allows for precise and robust measurements of chemotaxis speed and persistence characteristics at single-cell resolution. Using this assay, we established a reference set of migration speed values for neutrophils from healthy subjects. Comparisons with samples from burn patients revealed impaired directional migration speed starting as early as 24 hours after burn injury, reaching a minimum at 72-120 hours, correlated to the size of the burn injury and potentially serving as an early indicator for concurrent infections. Further characterization of neutrophil chemotaxis using this new assay may have important diagnostic implications not only for burn patients but also for patients afflicted by other diseases that compromise neutrophil functions.

  11. Plasma Diagnostics

    International Nuclear Information System (INIS)

    The success in achieving peaceful fusion power depends on the ability to control a high temperature plasma, which is an object with unique properties, possibly the most complicated object created by humans. Over years of fusion research a new branch of science has been created, namely plasma diagnostics, which involves knowledge of almost all fields of physics, from electromagnetism to nuclear physics, and up-to-date progress in engineering and technology (materials, electronics, mathematical methods of data treatment). Historically, work on controlled fusion started with pulsed systems and accordingly the methods of plasma parameter measurement were first developed for short lived and dense plasmas. Magnetically confined hot plasmas require the creation of special experimental techniques for diagnostics. The diagnostic set is the most scientifically intensive part of a plasma device. During many years of research operation some scientific tasks have been solved while new ones arose. New tasks often require significant changes in the diagnostic system, which is thus a very flexible part of plasma machines. Diagnostic systems are designed to solve several tasks. As an example here are the diagnostic tasks for the International Thermonuclear Experimental Reactor - ITER: (1) Measurements for machine protection and basic control; (2) Measurements for advanced control; (3) Additional measurements for performance evaluation and physics. Every new plasma machine is a further step along the path to the main goal - controlled fusion - and nobody knows in advance what new phenomena will be met on the way. So in the planning of diagnostic construction we should keep in mind further system upgrading to meet possible new scientific and technical challenges. (author)

  12. High Purity DNA Extraction with a SPE Microfluidic Chip Using KI as the Binding Salt

    Institute of Scientific and Technical Information of China (English)

    Xing CHEN; Da Fu CUI; Chang Chun LIU

    2006-01-01

    Based on solid phase extraction method, a novel silicon-PDMS-glass microchip for high purity DNA extraction has been developed by using KI as the binding salt. The microfluidic chip fabricated by MEMS technology was composed of a silicon substrate with a coiled channel and a compounded PDMS-glass cover. With this microfluidic chip, the wall of the coiled channel was used as solid phase matrix for binding DNA and DNA was extracted by the fluxion of the binding buffer, washing buffer and elution buffer. KI as a substitute for guanidine, was used successfully as binding salt for purification DNA, obtaining higher purity of genomic DNA and about 13.9 ng DNA from 1 μL rat whole blood in 35 minutes.

  13. Microfluidic device for acoustic cell lysis

    Energy Technology Data Exchange (ETDEWEB)

    Branch, Darren W.; Cooley, Erika Jane; Smith, Gennifer Tanabe; James, Conrad D.; McClain, Jaime L.

    2015-08-04

    A microfluidic acoustic-based cell lysing device that can be integrated with on-chip nucleic acid extraction. Using a bulk acoustic wave (BAW) transducer array, acoustic waves can be coupled into microfluidic cartridges resulting in the lysis of cells contained therein by localized acoustic pressure. Cellular materials can then be extracted from the lysed cells. For example, nucleic acids can be extracted from the lysate using silica-based sol-gel filled microchannels, nucleic acid binding magnetic beads, or Nafion-coated electrodes. Integration of cell lysis and nucleic acid extraction on-chip enables a small, portable system that allows for rapid analysis in the field.

  14. Detection methods for centrifugal microfluidic platforms.

    Science.gov (United States)

    Burger, Robert; Amato, Letizia; Boisen, Anja

    2016-02-15

    Centrifugal microfluidics has attracted much interest from academia as well as industry, since it potentially offers solutions for affordable, user-friendly and portable biosensing. A wide range of so-called fluidic unit operations, e.g. mixing, metering, liquid routing, and particle separation, have been developed and allow automation and integration of complex assay protocols in lab-on-a-disc systems. Besides liquid handling, the detection strategy for reading out the assay is crucial for developing a fully integrated system. In this review, we focus on biosensors and readout methods for the centrifugal microfluidics platform and cover optical as well as mechanical and electrical detection principles. PMID:26166363

  15. Microfluidic fuel cells for energy generation.

    Science.gov (United States)

    Safdar, M; Jänis, J; Sánchez, S

    2016-08-01

    Sustainable energy generation is of recent interest due to a growing energy demand across the globe and increasing environmental issues caused by conventional non-renewable means of power generation. In the context of microsystems, portable electronics and lab-on-a-chip based (bio)chemical sensors would essentially require fully integrated, reliable means of power generation. Microfluidic-based fuel cells can offer unique advantages compared to conventional fuel cells such as high surface area-to-volume ratio, ease of integration, cost effectiveness and portability. Here, we summarize recent developments which utilize the potential of microfluidic devices for energy generation. PMID:27367869

  16. Microfluidic Assessment of Frying Oil Degradation

    Science.gov (United States)

    Liu, Mei; Xie, Shaorong; Ge, Ji; Xu, Zhensong; Wu, Zhizheng; Ru, Changhai; Luo, Jun; Sun, Yu

    2016-06-01

    Monitoring the quality of frying oil is important for the health of consumers. This paper reports a microfluidic technique for rapidly quantifying the degradation of frying oil. The microfluidic device generates monodispersed water-in-oil droplets and exploits viscosity and interfacial tension changes of frying oil samples over their frying/degradation process. The measured parameters were correlated to the total polar material percentage that is widely used in the food industry. The results reveal that the steady-state length of droplets can be used for unambiguously assessing frying oil quality degradation.

  17. Microfluidic chip-capillary electrophoresis devices

    CERN Document Server

    Fung, Ying Sing; Du, Fuying; Guo, Wenpeng; Ma, Tongmei; Nie, Zhou; Sun, Hui; Wu, Ruige; Zhao, Wenfeng

    2015-01-01

    Capillary electrophoresis (CE) and microfluidic chip (MC) devices are relatively mature technologies, but this book demonstrates how they can be integrated into a single, revolutionary device that can provide on-site analysis of samples when laboratory services are unavailable. By introducing the combination of CE and MC technology, Microfluidic Chip-Capillary Electrophoresis Devices broadens the scope of chemical analysis, particularly in the biomedical, food, and environmental sciences.The book gives an overview of the development of MC and CE technology as well as technology that now allows

  18. Diffusion dynamics in microfluidic dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Balslev, Søren; Mortensen, Niels Asger;

    2007-01-01

    We have investigated the bleaching dynamics that occur in opto-fluidic dye lasers, where the liquid laser dye in a channel is locally bleached due to optical pumping. Our studies suggest that for micro-fluidic devices, the dye bleaching may be compensated through diffusion of dye molecules alone....... By relying on diffusion rather than convection to generate the necessary dye replenishment, our observation potentially allows for a significant simplification of opto-fluidic dye laser device layouts, omitting the need for cumbersome and costly external fluidic handling or on-chip micro-fluidic...

  19. Microfluidic Assessment of Frying Oil Degradation

    Science.gov (United States)

    Liu, Mei; Xie, Shaorong; Ge, Ji; Xu, Zhensong; Wu, Zhizheng; Ru, Changhai; Luo, Jun; Sun, Yu

    2016-01-01

    Monitoring the quality of frying oil is important for the health of consumers. This paper reports a microfluidic technique for rapidly quantifying the degradation of frying oil. The microfluidic device generates monodispersed water-in-oil droplets and exploits viscosity and interfacial tension changes of frying oil samples over their frying/degradation process. The measured parameters were correlated to the total polar material percentage that is widely used in the food industry. The results reveal that the steady-state length of droplets can be used for unambiguously assessing frying oil quality degradation. PMID:27312884

  20. Integrated Microfluidic Sensor System with Magnetostrictive Resonators

    KAUST Repository

    Liang, Cai

    2011-12-08

    The present embodiments describe a method that integrates a magnetostrictive sensor with driving and detecting elements into a microfluidic chip to detect a chemical, biochemical or biomedical species. These embodiments may also measure the properties of a fluid such as viscosity, pH values. The whole system can be referred to lab-on-a-chip (LOC) or micro-total-analysis-systems (.mu.TAS). In particular, this present embodiments include three units, including a microfluidics unit, a magnetostrictive sensor, and driving/detecting elements. An analyzer may also be provided to analyze an electrical signal associated with a feature of a target specimen.

  1. Scalable evaluation of platelet aggregation by the degree of blood migration

    Science.gov (United States)

    Song, Suk-Heung; Lim, Chae-Seung; Shin, Sehyun

    2013-12-01

    Platelet aggregation plays a key role in vascular thrombosis. Antiplatelet drug therapy is commonly used for the prevention of abnormal platelet aggregation. So, measuring platelet aggregation function is critically important in clinical field. Here, we introduce a scalable evaluation method of platelet aggregation measured with the degree of blood migration through microchannel in a microfluidic chip. Unlike conventional methods that require expertise with system physics to operate devices, our approach is using microfluidics system, which requires only a syringe vacuum. The scalable migration factors, migration distance and touchdown time, are capable of distinguishing various antiplatelet drug effects under microfluidics and would be effective for the quick and easy evaluation of quantitative platelet aggregation.

  2. Pulsatile microfluidics as an analytical tool for determining the dynamic characteristics of microfluidic systems

    International Nuclear Information System (INIS)

    An understanding of all fluid dynamic time scales is needed to fully understand and hence exploit the capabilities of fluid flow in microfluidic systems. We propose the use of harmonically oscillating microfluidics as an analytical tool for the deduction of these time scales. Furthermore, we suggest the use of system-level equivalent circuit theory as an adequate theory of the behavior of the system. A novel pressure source capable of operation in the desired frequency range is presented for this generic analysis. As a proof of concept, we study the fairly complex system of water-filled interconnected elastic microfluidic tubes containing a large, trapped air bubble and driven by a pulsatile pressure difference. We demonstrate good agreement between the system-level model and the experimental results, allowing us to determine the dynamic time scales of the system. However, the generic analysis can be applied to all microfluidic systems, both ac and dc.

  3. Combining rapid diagnostic tests and dried blood spot assays for point-of-care testing of human immunodeficiency virus, hepatitis B and hepatitis C infections in Burkina Faso, West Africa.

    Science.gov (United States)

    Kania, D; Bekalé, A M; Nagot, N; Mondain, A-M; Ottomani, L; Meda, N; Traoré, M; Ouédraogo, J B; Ducos, J; Van de Perre, P; Tuaillon, E

    2013-12-01

    People screened for human immunodeficiency virus (HIV) using rapid diagnostic tests (RDTs) in Africa remain generally unaware of their status for hepatitis B (HBV) and hepatitis C (HCV) infections. We evaluated a two-step screening strategy in Burkina Faso, using both HIV RDTs and Dried Blood Spot (DBS) assays to confirm an HIV-positive test, and to test for HBV and HCV infections. HIV counselling and point-of-care testing were performed at a voluntary counselling and testing centre with HBV, HCV status and HIV confirmation using DBS specimens, being assessed at a central laboratory. Serological testing on plasma was used as the reference standard assay to control for the performance of DBS assays. Nineteen out of 218 participants included in the study were positive for HIV using RDTs. A fourth-generation HIV ELISA and immunoblot assays on DBS confirmed HIV status. Twenty-four out of 25 participants infected with HBV were found positive for hepatitis B surface antigen (HBsAg) using DBS. One sample with a low HBsAg concentration on plasma was not detected on DBS. Five participants tested positive for HCV antibodies were confirmed positive with an immunoblot assay using DBS specimens. Laboratory results were communicated within 7 days to participants with no loss to follow up of participants between the first and second post-test counselling sessions. In conclusion, DBS collection during HIV point-of-care testing enables screening and confirmation of HBV, HCV and HIV infections. Diagnosis using DBS may assist with implementation of national programmes for HBV, HCV and HIV screening and clinical care in middle- to low-income countries. PMID:23902574

  4. Expanding Imaging Capabilities for Microfluidics: Applicability of Darkfield Internal Reflection Illumination (DIRI) to Observations in Microfluidics

    OpenAIRE

    Yoshihiro Kawano; Chino Otsuka; James Sanzo; Christopher Higgins; Tatsuo Nirei; Tobias Schilling; Takuji Ishikawa

    2015-01-01

    Microfluidics is used increasingly for engineering and biomedical applications due to recent advances in microfabrication technologies. Visualization of bubbles, tracer particles, and cells in a microfluidic device is important for designing a device and analyzing results. However, with conventional methods, it is difficult to observe the channel geometry and such particles simultaneously. To overcome this limitation, we developed a Darkfield Internal Reflection Illumination (DIRI) system tha...

  5. Diagnostic development

    International Nuclear Information System (INIS)

    During the past year the far-infrared or submillimeter diagnostic research program resulted in three major developments: (1) an optically pumped 0.385-μm D2O-laser oscillator-amplifier system was operated at a power level of 1 MW with a line width of less than 50 MHz; (2) a conical Pyrex submillimeter laser beam dump with a retention efficiency greater than 104 was developed for the ion temperature Thompson scattering experiment; and (3) a new diagnostic technique was developed that makes use of the Faraday rotation of a modulated submillimeter laser beam to determine plasma current profile. Measurements of the asymmetric distortion of the H/sub α/ (6563 A) spectral line profile show that the effective toroidal drift velocity, dv/sub two vertical bars i/dT/sub i/, may be used as an indicator of plasma quality and as a complement to other ion temperature diagnostics

  6. Whole blood pumping with a microthrottle pump

    OpenAIRE

    Davies, M J; Johnston, I. D.; Tan, C. K. L.; Tracey, M. C.

    2010-01-01

    We have previously reported that microthrottle pumps (MTPs) display the capacity to pump solid phase suspensions such as polystyrene beads which prove challenging to most microfluidic pumps. In this paper we report employing a linear microthrottle pump (LMTP) to pump whole, undiluted, anticoagulated, human venous blood at 200 μl min−1 with minimal erythrocyte lysis and no observed pump blockage. LMTPs are particularly well suited to particle suspension transport by virtue of their relatively ...

  7. Blood pressure

    Science.gov (United States)

    ... the walls of the arteries is called blood pressure. Blood pressure is measured both as the heart contracts, which ... as it relaxes, which is called diastole. Normal blood pressure is considered to be a systolic blood pressure ...

  8. Blood transfusions

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000431.htm Blood transfusions To use the sharing features on this ... several sources of blood which are described below. Blood From the Public (Volunteer Blood Donation) The most ...

  9. Blood Basics

    Science.gov (United States)

    ... Patient Group Links Advocacy Toolkit Home For Patients Blood Basics Blood is a specialized body fluid. It ... about 9 pints. Jump To: The Components of Blood and Their Importance Many people have undergone blood ...

  10. Blood Thinners

    Science.gov (United States)

    If you have some kinds of heart or blood vessel disease, or if you have poor blood flow to your brain, your doctor may recommend that you take a blood thinner. Blood thinners reduce the risk of heart ...

  11. Blood culture

    Science.gov (United States)

    Culture - blood ... A blood sample is needed . The site where blood will be drawn is first cleaned with an antiseptic such ... organism from the skin getting into (contaminating) the blood sample and causing a false-positive result (see ...

  12. Automated and miniaturized detection of biological threats with a centrifugal microfluidic system

    Science.gov (United States)

    Mark, D.; van Oordt, T.; Strohmeier, O.; Roth, G.; Drexler, J.; Eberhard, M.; Niedrig, M.; Patel, P.; Zgaga-Griesz, A.; Bessler, W.; Weidmann, M.; Hufert, F.; Zengerle, R.; von Stetten, F.

    2012-06-01

    The world's growing mobility, mass tourism, and the threat of terrorism increase the risk of the fast spread of infectious microorganisms and toxins. Today's procedures for pathogen detection involve complex stationary devices, and are often too time consuming for a rapid and effective response. Therefore a robust and mobile diagnostic system is required. We present a microstructured LabDisk which performs complex biochemical analyses together with a mobile centrifugal microfluidic device which processes the LabDisk. This portable system will allow fully automated and rapid detection of biological threats at the point-of-need.

  13. Microfluidic approach for fast labeling optimization and dose-on-demand implementation

    International Nuclear Information System (INIS)

    Introduction: The diffusion of PET as a pivotal molecular imaging modality has emphasized the need for new positron-emitting radiotracers to be used in diagnostic applications and research. Microfluidic represents an innovative approach, owing to its potential to increase radiochemical productivity in terms of yields, time reduction, precursor consumption and flexible experimental planning. Methods: We focused on fluorine-18 labeling and used a microfluidic platform to perform sequential reactions, by using the same batch of 18F-labeling solution on one or more substrates, during the same experimental session. A solid-phase extraction (SPE) workup procedure was also implemented in the system to provide a repeatable purification step. Results: We were able to quickly optimize the conditions for labeling of ethyl and propyl ditosylate and of a new cannabinoid type 2 (CB2) receptor agonist, CB41. In all substrates, we obtained good incorporation yields (60% to 85%) in short (18F-fluoride batch. This approach was used to obtain in sequence several injectable doses of a novel CB2 ligand, thus providing the proof of principle that microfluidic systems permit a dose-on-demand production of new radiotracers.

  14. Direct 3D-printing of cell-laden constructs in microfluidic architectures.

    Science.gov (United States)

    Liu, Justin; Hwang, Henry H; Wang, Pengrui; Whang, Grace; Chen, Shaochen

    2016-04-21

    Microfluidic platforms have greatly benefited the biological and medical fields, however standard practices require a high cost of entry in terms of time and energy. The utilization of three-dimensional (3D) printing technologies has greatly enhanced the ability to iterate and build functional devices with unique functions. However, their inability to fabricate within microfluidic devices greatly increases the cost of producing several different devices to examine different scientific questions. In this work, a variable height micromixer (VHM) is fabricated using projection 3D-printing combined with soft lithography. Theoretical and flow experiments demonstrate that altering the local z-heights of VHM improved mixing at lower flow rates than simple geometries. Mixing of two fluids occurs as low as 320 μL min(-1) in VHM whereas the planar zigzag region requires a flow rate of 2.4 mL min(-1) before full mixing occurred. Following device printing, to further demonstrate the ability of this projection-based method, complex, user-defined cell-laden scaffolds are directly printed inside the VHM. The utilization of this unique ability to produce 3D tissue models within a microfluidic system could offer a unique platform for medical diagnostics and disease modeling. PMID:26980159

  15. Polydimethylsiloxane microfluidic chemiluminescence immunodevice with the signal amplification strategy for sensitive detection of human immunoglobin G.

    Science.gov (United States)

    Li, Huifang; Zhao, Mei; Liu, Wei; Chu, Weiru; Guo, Yumei

    2016-01-15

    A polydimethylsiloxane (PDMS) microfluidic chemiluminescence (CL) immunodevice for sensitive detection of human immunoglobin G (IgG) with the signal amplification strategy was developed in this work. The immunodevice was prepared by covalently immobilizing capture antibodies (Abs) on the silanized microchannel of microfluidic chip. Gold nanoparticles (AuNPs) functionalized with a high molar ratio of horseradish peroxidase (HRP) were used as an Ab label for signal amplification. Using a sandwich immunoassay, the multi-HRP conjugated AuNPs can catalyze the luminol-H2O2 CL system to achieve the high sensitivity. In addition, the double spiral flow-channel was adopted here, which can still contribute to the high sensitivity. Based on signal amplification strategy, the performance of human IgG tests revealed a lower detection limit (DL) of 0.03ng/mL and showed an increase of 7.4-fold in detection sensitivity compared to a commercial Ab-HRP conjugation. This microfluidic immunodevice can provide an alternative approach for sensitive detection of human IgG in the field of clinic diagnostic and therapeutic. PMID:26592629

  16. Scintillation detectors based on silicon microfluidic channels

    International Nuclear Information System (INIS)

    Microfluidic channels obtained by SU-8 photolithography and filled with liquid scintillators were recently demonstrated to be an interesting technology for the implementation of novel particle detectors. The main advantages of this approach are the intrinsic radiation resistance resulting from the simple microfluidic circulation of the active medium and the possibility to manufacture devices with high spatial resolution and low material budget using microfabrication techniques. Here we explore a different technological implementation of this concept, reporting on scintillating detectors based on silicon microfluidic channels. A process for manufacturing microfluidic devices on silicon substrates, featuring microchannel arrays suitable for light guiding, was developed. Such process can be in principle combined with standard CMOS processing and lead to a tight integration with the readout photodetectors and electronics in the future. Several devices were manufactured, featuring microchannel geometries differing in depth, width and pitch. A preliminary characterization of the prototypes was performed by means of a photomultiplier tube coupled to the microchannel ends, in order to detect the scintillation light produced upon irradiation with beta particles from a 90Sr source. The photoelectron spectra thus obtained were fitted with the expected output function in order to extract the light yield

  17. Droplet microfluidics in (bio) chemical analysis

    Czech Academy of Sciences Publication Activity Database

    Basova, E. Y.; Foret, František

    2015-01-01

    Roč. 140, č. 1 (2015), s. 22-38. ISSN 0003-2654 R&D Projects: GA ČR(CZ) GBP206/12/G014 Institutional support: RVO:68081715 Keywords : droplet chemistry * bioanalysis * microfluidics * protein Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.107, year: 2014

  18. Application of membrane technology in microfluidic devices

    NARCIS (Netherlands)

    Jong, de Jorrit

    2008-01-01

    This thesis describes the application of membrane technology in microfluidic systems. The word ‘microfluidic’ refers to the research field that develops methods and devices to control, manipulate, and analyze flows in sub‐millimeter dimensions. General advantages of this miniaturization strategy inc

  19. A noble microfluidic device for protein crystallizations.

    Science.gov (United States)

    Shim, Jung-Uk; Fraden, Seth

    2006-03-01

    A high throughput, low volume microfluidic device has been constructed out of poly(dimethylsiloxane) elastomer. We have demonstrated that sub-nanoliter water-in-oil drops of protein solutions of different composition can be rapidly stored in individual wells, which allows screening of 1000 conditions while consuming a total of only 1 microgram protein on a 20 cm^2 chip. This reduction in protein needed for crystal screens allows high-throughput crystallization of mammalian proteins expressed in tissue culture. A significant advance over current microfluidic devices is that each pot is in contact with a reservoir through a dialysis membrane which only water and other low molecular weight organic solvents can pass, but not salt, polymer or amphiphile. This enables the concentration of all solutes in a solution to be reversibly, rapidly, and precisely varied in contrast to current microfluidic methods, which are irreversible. This microfluidic dialysis technology solves a major problem in protein crystallization, the decoupling of nucleation from growth. The device will also be useful for general studies of the phase behavior of protein solutions.

  20. Subdynamic Asymptotic Behavior of Microfluidic Valves

    Czech Academy of Sciences Publication Activity Database

    Tesař, Václav; Tippets, J.R.; Allen, R.W.K.; Low, Y.Y.

    2005-01-01

    Roč. 14, č. 2 (2005), s. 335-347. ISSN 1057-7157 Institutional research plan: CEZ:AV0Z20760514 Keywords : low Reynolds number * microfluidics * no-moving-part valves Subject RIV: BK - Fluid Dynamics Impact factor: 3.005, year: 2005

  1. Scintillation detectors based on silicon microfluidic channels

    Science.gov (United States)

    Maoddi, P.; Mapelli, A.; Bagiacchi, P.; Gorini, B.; Haguenauer, M.; Lehmann Miotto, G.; Murillo Garcia, R.; Safai Tehrani, F.; Veneziano, S.; Renaud, P.

    2014-01-01

    Microfluidic channels obtained by SU-8 photolithography and filled with liquid scintillators were recently demonstrated to be an interesting technology for the implementation of novel particle detectors. The main advantages of this approach are the intrinsic radiation resistance resulting from the simple microfluidic circulation of the active medium and the possibility to manufacture devices with high spatial resolution and low material budget using microfabrication techniques. Here we explore a different technological implementation of this concept, reporting on scintillating detectors based on silicon microfluidic channels. A process for manufacturing microfluidic devices on silicon substrates, featuring microchannel arrays suitable for light guiding, was developed. Such process can be in principle combined with standard CMOS processing and lead to a tight integration with the readout photodetectors and electronics in the future. Several devices were manufactured, featuring microchannel geometries differing in depth, width and pitch. A preliminary characterization of the prototypes was performed by means of a photomultiplier tube coupled to the microchannel ends, in order to detect the scintillation light produced upon irradiation with beta particles from a 90Sr source. The photoelectron spectra thus obtained were fitted with the expected output function in order to extract the light yield.

  2. Wax-bonding 3D microfluidic chips

    KAUST Repository

    Gong, Xiuqing

    2013-10-10

    We report a simple, low-cost and detachable microfluidic chip incorporating easily accessible paper, glass slides or other polymer films as the chip materials along with adhesive wax as the recycling bonding material. We use a laser to cut through the paper or film to form patterns and then sandwich the paper and film between glass sheets or polymer membranes . The hot-melt adhesive wax can realize bridge bonding between various materials, for example, paper, polymethylmethacrylate (PMMA) film, glass sheets, or metal plate. The bonding process is reversible and the wax is reusable through a melting and cooling process. With this process, a three-dimensional (3D) microfluidic chip is achievable by vacuating and venting the chip in a hot-water bath. To study the biocompatibility and applicability of the wax-based microfluidic chip, we tested the PCR compatibility with the chip materials first. Then we applied the wax-paper based microfluidic chip to HeLa cell electroporation (EP ). Subsequently, a prototype of a 5-layer 3D chip was fabricated by multilayer wax bonding. To check the sealing ability and the durability of the chip, green fluorescence protein (GFP) recombinant Escherichia coli (E. coli) bacteria were cultured, with which the chemotaxis of E. coli was studied in order to determine the influence of antibiotic ciprofloxacin concentration on the E. coli migration.

  3. Microfluidic desalination techniques and their potential applications

    NARCIS (Netherlands)

    Roelofs, S.H.; Berg, van den A.; Odijk, M.

    2015-01-01

    In this review we discuss recent developments in the emerging research field of miniaturized desalination. Traditionally desalination is performed to convert salt water into potable water and research is focused on improving performance of large-scale desalination plants. Microfluidic desalination o

  4. Understanding cell passage through constricted microfluidic channels

    Science.gov (United States)

    Cartas-Ayala, Marco A.; Karnik, Rohit

    2012-11-01

    Recently, several microfluidic platforms have been proposed to characterize cells based on their behaviour during cell passage through constricted channels. Variables like transit time have been analyzed in disease states like sickle cell anemia, malaria and sepsis. Nevertheless, it is hard to make direct comparisons between different platforms and cell types. We present experimental results of the relationship between solid deformable particle properties, i.e. stiffness and relative particle size, and flow properties, i.e. particle's velocity. We measured the hydrodynamic variables during the flow of HL-60 cells, a white myeloid cell type, in narrow microfluidic square channels using a microfluidic differential manometer. We measured the flow force required to move cells of different sizes through microchannels and quantified friction forces opposing cell passage. We determined the non-dimensional parameters that influence the flow of cells and we used them to obtain a non dimensional expression that can be used to predict the forces needed to drive cells through microchannels. We found that the friction force needed to flow HL-60 through a microfluidic channel is the sum of two parts. The first part is a static friction force that is proportional to the force needed to keep the force compressed. The second part is a factor that is proportional to the cell velocity, hence a dynamic term, and slightly sensitive to the compressive force. We thank CONACYT (Mexican Science and Technology Council) for supporting this project, grant 205899.

  5. Microfluidic distillation chip for methanol concentration detection.

    Science.gov (United States)

    Wang, Yao-Nan; Liu, Chan-Chiung; Yang, Ruey-Jen; Ju, Wei-Jhong; Fu, Lung-Ming

    2016-03-17

    An integrated microfluidic distillation system is proposed for separating a mixed ethanol-methanol-water solution into its constituent components. The microfluidic chip is fabricated using a CO2 laser system and comprises a serpentine channel, a boiling zone, a heating zone, and a cooled collection chamber filled with de-ionized (DI) water. In the proposed device, the ethanol-methanol-water solution is injected into the microfluidic chip and driven through the serpentine channel and into the collection chamber by means of a nitrogen carrier gas. Following the distillation process, the ethanol-methanol vapor flows into the collection chamber and condenses into the DI water. The resulting solution is removed from the collection tank and reacted with a mixed indicator. Finally, the methanol concentration is inversely derived from the absorbance measurements obtained using a spectrophotometer. The experimental results show the proposed microfluidic system achieves an average methanol distillation efficiency of 97%. The practicality of the proposed device is demonstrated by detecting the methanol concentrations of two commercial fruit wines. It is shown that the measured concentration values deviate by no more than 3% from those obtained using a conventional bench top system. PMID:26920777

  6. Droplet microfluidics in (bio) chemical analysis

    Czech Academy of Sciences Publication Activity Database

    Basova, E. Y.; Foret, František

    2015-01-01

    Roč. 140, č. 1 (2015), s. 22-38. ISSN 0003-2654 R&D Projects: GA ČR(CZ) GBP206/12/G014 Institutional support: RVO:68081715 Keywords : droplet chemistry * bioanalysis * microfluidics * protein Subject RIV: CB - Analytical Chemistry , Separation Impact factor: 4.107, year: 2014

  7. Inventions Utilizing Microfluidics and Colloidal Particles

    Science.gov (United States)

    Marr, David W.; Gong, Tieying; Oakey, John; Terray, Alexander V.; Wu, David T.

    2009-01-01

    Several related inventions pertain to families of devices that utilize microfluidics and/or colloidal particles to obtain useful physical effects. The families of devices can be summarized as follows: (1) Microfluidic pumps and/or valves wherein colloidal-size particles driven by electrical, magnetic, or optical fields serve as the principal moving parts that propel and/or direct the affected flows. (2) Devices that are similar to the aforementioned pumps and/or valves except that they are used to manipulate light instead of fluids. The colloidal particles in these devices are substantially constrained to move in a plane and are driven to spatially order them into arrays that function, variously, as waveguides, filters, or switches for optical signals. (3) Devices wherein the ultra-laminar nature of microfluidic flows is exploited to effect separation, sorting, or filtering of colloidal particles or biological cells in suspension. (4) Devices wherein a combination of confinement and applied electrical and/or optical fields forces the colloidal particles to become arranged into three-dimensional crystal lattices. Control of the colloidal crystalline structures could be exploited to control diffraction of light. (5) Microfluidic devices, incorporating fluid waveguides, wherein switching of flows among different paths would be accompanied by switching of optical signals.

  8. Micromechanical photothermal analyser of microfluidic samples

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to a micromechanical photothermal analyser of microfluidic samples comprising an oblong micro-channel extending longitudinally from a support element, the micro-channel is made from at least two materials with different thermal expansion coefficients, wherein the...

  9. Design of microfluidic bioreactors using topology optimization

    DEFF Research Database (Denmark)

    Okkels, Fridolin; Bruus, Henrik

    2007-01-01

    We address the design of optimal reactors for supporting biological cultures using the method of topology optimization. For some years this method have been used to design various optimal microfluidic devices.1-4 We apply this method to distribute optimally biologic cultures within a flow of...

  10. Biocatalytic process development using microfluidic miniaturized systems

    DEFF Research Database (Denmark)

    Krühne, Ulrich; Heintz, Søren; Ringborg, Rolf Hoffmeyer;

    2014-01-01

    The increasing interest in biocatalytic processes means there is a clear need for a new systematic development paradigm which encompasses both protein engineering and process engineering. This paper argues that through the use of a new microfluidic platform, data can be collected more rapidly and...

  11. Laser-direct-write technique for rapid prototyping of multiplexed paper-based diagnostic sensors

    OpenAIRE

    He, Peijun; Katis, Ioannis; Eason, Robert; Sones, Collin

    2015-01-01

    We report the successful demonstration of a laser-based direct-write technique for patterning of various porous materials to fabricate more diversified and multifunctional paper-based microfluidic devices that find applications in affordable point-of-care medical diagnostics

  12. Diagnostic test

    International Nuclear Information System (INIS)

    A diagnostic test is provided based on competitive binding in which a partition coefficient is established for the substance whose concentration is to be determined and for the radioactive labeled form of the substance between liquid and solid phases. 10 claims

  13. Digital microfluidic operations on micro-electrode dot array architecture.

    Science.gov (United States)

    Wang, G; Teng, D; Fan, S-K

    2011-12-01

    As digital microfluidics-based biochips find more applications, their complexity is expected to increase significantly owing to the trend of multiple and concurrent assays on the chip. There is a pressing need to deliver a top-down design methodology that the biochip designer can leverage the same level of computer-aided design support as the semi-conductor industry now does. Moreover, as microelectronics fabrication technology is scaling up and integrated device performance is improving, it is expected that these microfluidic biochips will be integrated with microelectronic components in next-generation system-on-chip designs. This study presents the analysis and experiments of digital microfluidic operations on a novel electrowetting-on-dielectric-based 'micro-electrode dot array architecture' that fosters a development path for hierarchical top-down design approach for digital microfluidics. The proposed architecture allows dynamic configurations and activations of identical basic microfluidic unit called 'micro-electrode cells' to design microfluidic components, layouts, routing, microfluidic operations and applications of the biochip hierarchically. Fundamental microfluidic operations have been successfully performed by the architecture. In addition, this novel architecture demonstrates a number of advantages and flexibilities over the conventional digital microfluidics in performing advanced microfluidic operations. PMID:22149873

  14. Solar thermal polymerase chain reaction for smartphone-assisted molecular diagnostics

    OpenAIRE

    Li Jiang; Matthew Mancuso; Zhengda Lu; Gunkut Akar; Ethel Cesarman; David Erickson

    2014-01-01

    Nucleic acid-based diagnostic techniques such as polymerase chain reaction (PCR) are used extensively in medical diagnostics due to their high sensitivity, specificity and quantification capability. In settings with limited infrastructure and unreliable electricity, however, access to such devices is often limited due to the highly specialized and energy-intensive nature of the thermal cycling process required for nucleic acid amplification. Here we integrate solar heating with microfluidics ...

  15. An integrated microfluidic system for diagnosis of the resistance of Helicobacter pylori to quinolone-based antibiotics.

    Science.gov (United States)

    Chao, Chih-Yu; Wang, Chih-Hung; Che, Yu-Jui; Kao, Cheng-Yen; Wu, Jiunn-Jong; Lee, Gwo-Bin

    2016-04-15

    Helicobacter pylori (H. pylori) is a species of bacteria that can colonize the human stomach mucosa. It is closely associated with gastric diseases such as ulcer and inflammation. Recently, some H. pylori strains were found to express resistance to a family of antibiotics known as quinolones due to single-point mutations. Although traditional polymerase chain reaction (PCR) and molecular diagnostic-based approaches can be used to determine the presence and abundance of antibiotic-resistant H. pylori strains, such processes are relatively expensive, labor-intensive, and require bulky and costly equipment. This study therefore reports an advanced diagnostic assay performed on an integrated microfluidic system for rapid detection of antibiotic resistance in H. pylori. The assay features three components: (1) nucleic acid extraction by specific probe-conjugated magnetic beads, (2) amplification of the target deoxyribonucleic acid (DNA) fragments by using single-nucleotide-polymorphism polymerase chain reaction (SNP-PCR), and (3) optical detection of the PCR products. The device integrates several microfluidic components including micro-pumps, normally-closed micro-valves, and reaction chambers such that the entire diagnostic assay can be automatically executed on a single microfluidic system within one hour with detection limits of 10(0), 10(2), and 10(2) bacterial cells for H. pylori detection and two different SNP sites strains. Three PCR-based assays for determining presence of H. pylori infection and two DNA single-point mutation assays aimed at determining whether the infected strains were resistant to quinolone can be performed simultaneously on a single chip, suggesting that this microfluidic system could be a promising tool for rapid diagnosis of the presence of antibiotic-resistant H. pylori strains. PMID:26630283

  16. Integrated Amplification Microarrays for Infectious Disease Diagnostics

    Directory of Open Access Journals (Sweden)

    Darrell P. Chandler

    2012-11-01

    Full Text Available This overview describes microarray-based tests that combine solution-phase amplification chemistry and microarray hybridization within a single microfluidic chamber. The integrated biochemical approach improves microarray workflow for diagnostic applications by reducing the number of steps and minimizing the potential for sample or amplicon cross-contamination. Examples described herein illustrate a basic, integrated approach for DNA and RNA genomes, and a simple consumable architecture for incorporating wash steps while retaining an entirely closed system. It is anticipated that integrated microarray biochemistry will provide an opportunity to significantly reduce the complexity and cost of microarray consumables, equipment, and workflow, which in turn will enable a broader spectrum of users to exploit the intrinsic multiplexing power of microarrays for infectious disease diagnostics.

  17. Diagnostic Criteria

    Directory of Open Access Journals (Sweden)

    Narender P. Van Orshoven

    2010-01-01

    Full Text Available The aims of this study were to find out whether Postprandial hypotension (PPH occurs more frequently in patients admitted to a geriatric ward than in healthy elderly individuals, what the optimal interval between blood pressure measurements is in order to diagnose PPH and how often it is associated with symptoms.The result of this study indicates that PPH is present in a high number of frail elderly, but also in a few healthy older persons. Measuring blood pressure at least every 10 minutes for 60 minutes after breakfast will adequately diagnose PPH, defined as >20 mmHg systolic fall, in most patients. However with definition of PPH as >30 mmHg systolic fall, measuring blood pressure every 10 minutes will miss PPH in one of three patients. With the latter definition of PPH the presence of postprandial complaints is not associated with the existence of PPH.

  18. Separation of blood in microchannel bends

    Science.gov (United States)

    Blattert, Christoph; Jurischka, Reinhold; Schoth, Andreas; Kerth, Paul; Menz, Wolfgang

    2004-01-01

    Biological applications of micro assay devices require integrated on-chip microfluidics for separation of plasma or serum from blood. This is achieved by a new blood separation technique based on a microchannel bend structure developed within the collaborative Micro-Tele-BioChip (μTBC) project co-funded by the German Ministry For Education and Research (BMBF). Different prototype polymer chips have been manufactured with an UV-LIGA process and hot embossing technology. The separation efficiency of these chips has been determined by experimental measurements using human whole blood. Results show different separation efficiencies for cells and plasma depending on microchannel geometry and blood sample characteristics and suggest an alternative blood separation method as compared to existing micro separation technologies.

  19. Fundamentals and applications of inertial microfluidics: a review.

    Science.gov (United States)

    Zhang, Jun; Yan, Sheng; Yuan, Dan; Alici, Gursel; Nguyen, Nam-Trung; Ebrahimi Warkiani, Majid; Li, Weihua

    2016-01-01

    In the last decade, inertial microfluidics has attracted significant attention and a wide variety of channel designs that focus, concentrate and separate particles and fluids have been demonstrated. In contrast to conventional microfluidic technologies, where fluid inertia is negligible and flow remains almost within the Stokes flow region with very low Reynolds number (Re ≪ 1), inertial microfluidics works in the intermediate Reynolds number range (~1 developments and key applications of inertial microfluidic systems according to their microchannel structures. Finally, we discuss the perspective of employing fluid inertia in microfluidics for particle manipulation. Due to the superior benefits of inertial microfluidics, this promising technology will still be an attractive topic in the near future, with more novel designs and further applications in biology, medicine and industry on the horizon. PMID:26584257

  20. Novel Diagnostic Method for Personalized Treatment of Cancer

    DEFF Research Database (Denmark)

    Zulfiqar, Azeem

    pressure, glucose, hemoglobin, cholesterol level in the blood and many more. The efforts are now being made to develop a Point-Of-Care Technology (POCT) that can detect cancer at an early and potentially treatable stage. To fulfill this requirement, a highly sensitive sensing technology is needed that can...... detect very small amount of cancer markers in the blood drop to be used in a POC device. Silicon Nanowires (SiNW) in a field effect setup have been demonstrated as a highly sensitive tool that can be used to detect very small amount of biomolecules. However, the manufacturing method to produce them......-microfluidic system on top of SiNW is demonstrated. The durability of the microfluidic system has also been tested. In the third part, different functionalization methods are explained and used to demonstrate the bio sensing on the SiNW sensor. The detection of cancer biomarker is also tested on these devices. Lastly...