Lab-on-a-Chip Fabrication and Application

The necessity of on-site, fast, sensitive, and cheap complex laboratory analysis, associated with the advances in the microfabrication technologies and the microfluidics, made it possible for the creation of the innovative device lab-on-a-chip (LOC), by which we would be able to scale a single or multiple laboratory processes down to a chip format. The present book is dedicated to the LOC devices from two points of view: LOC fabrication and LOC application

Manipulation and Detection of Superparamagnetic Beads with Spin-Valves

This work describes a new magnetic manipulation technique to trap, release, transport, and detect superparamagnetic beads (SPBs) with low-power and addressable spin-valves (SVs). Functionalized SPBs are used as \u22mobile substrates\u22 or magnetic tags in numerous bioassays. Examples of applicable bioassays include protein and DNA purification, cell fractionation, enzyme immobilization, and immunoassays. SV technology is based on the giant magnetoresistance (GMR) effect and is commonly used in high-density magnetic recording heads and magnetic field sensors. The SV consist of two magnetic layers separated by a spacer layer. An antiferromagnetic (AFM) layer pins the magnetization of one ferromagnetic (FM) layer in one direction while the other FM layer remains free to rotate. When the two layers are parallel (low resistance state), the high magnetic field gradient will attract and trap a SPB. When the two layers are antiparallel (high resistance state), the gradient is low and the SPB will no longer be attracted to the SV; the SPB will be released. In addition to SPB capture and release, the stray fields from a trapped and magnetized SPB affect the SV resistance response, thus a trapped SPB can be detected. The scope of this thesis includes the design, fabrication, and characterization of the microfluidic and micro-electromechanical system (MEMS) to manipulate and detect SPBs with nonvolatile and locally addressable SVs

Laboratoire sur puce pour la séparation et détection des particules à base de diélectrophorèse à basse tension

Résumé Notre recherche est construite autour de la volonté de développer et d'élargir l'utilisation des laboratoires sur puce (LsP), d'y intégrer de nouvelles fonctions et de proposer des approches de modélisation plus rigoureuses. En effet, les travaux de pointe montrent que pour réaliser des modèles mimant le plus fidèlement possible les systèmes vivants, les LsP doivent évoluer des simples supports fonctionnalisés que sont les puces d'analyse et de séparation de l'ADN vers des systèmes intégrant davantage de fonctions. Pour ce faire, nous proposons tout d'abord un premier prototype d'un LsP comprenant des modules microélectroniques, microfluidiques, de communication radio fréquence et d'alimentation intégrée, pour la séparation des particules avec des validations in-vitro. Cette plateforme a pour objectif d'observer le comportement des particules face à une variation de la fréquence, de la phase ou de l'amplitude du champ électrique avec différentes architectures d'électrodes. De plus, étant programmable et reconfigurable, elle nous a permis de valider plusieurs concepts, notamment l'identification fréquentielle des micro et nanoparticules. Cette dernière représente notre principale contribution qui pourrait, éventuellement, ouvrir la porte à plusieurs recherches notamment celles portant sur l'identification des maladies neurodégénératives. Notre but étant d’offrir une grande flexibilité dans la modélisation, nous présentons une nouvelle approche pour modéliser les LsP dans laquelle le comportement des particules est modélisé en tenant compte de l'architecture des électrodes, des signaux appliqués et des propriétés biologiques du milieu. Cette première modélisation en son genre est une approche hybride combinant une modélisation par éléments finis à l’aide d’ANSYS et une implémentation d’un algorithme sur Matlab. Elle permet de calculer la position d'une particule dans un microcanal en se basant sur les résultats fournis par ANSYS. Cette modélisation présente de nombreux avantages dont notamment, la possibilité d’identifier l’emplacement d'une particule avec précision en 3D, en plus de valider la séparation des particules à travers toute la profondeur du microcanal, ce qui n'est pas possible en se basant uniquement sur les résultats expérimentaux. De plus, nous avons fabriqué le système complet avec une architecture 3D de 5 PCB, une plateforme microfluidique, un contrôle sans fil par Bluetooth et un bloc d'alimentation programmable et intégré dans un même microsystème. Toute la partie microélectronique du LsP a été implémentée sur une puce microélectronique fabriquée avec la technologie CMOS 0.18 um de TSMC. Quant à l'architecture microfluidique, elle a été fabriquée avec les procédé Sensonit et Lionix.----------Abstract Our research project is devoted to develop and extend the use of laboratories on chip (LoC), and to add to them new functions and more rigorous modeling techniques. Without a doubt, the state of art shows that, in order to create models that reflect living organisms best, LoCs need be more evolved systems that serve more functions than simple and limited-function DNA chips. To do so, we propose a first prototype of a Lab on Chip with microelectronic and microfluidic modules, and integrated radio-frequency communication and power supply to separate the different particles in the cerebrospinal fluid with validations done in vitro. The purpose of this platform is to observe the particles' behaviour when facing a change in the electric field's, frequency, phase, or amplitude, all this using different architectures of electrodes. Moreover, the platform is programmable and reconfigurable, which is important as it allows the validation of many concepts, such as the frequency separation of micro and nanoparticles. This platform actually represents our main focus in this research. We believe that it will eventually lead to many other research and medical advancements, such as identifying the source of many degenerative neurological disorders. We also came up with an innovative approach to give a greater flexibility to the modeling of LoCs. This approach consists of modeling the behaviour of particles based on the architectural design of the electrodes, the applied signals, and the biological properties of the medium. This first type of modeling is based on a hybrid approach between a Finete element modeling using ANSYS, and an algorithmic implementation on Matlab that makes it possible to calculate each particle's position in a micro canal based on the results provided by ANSYS. Such modeling has many advantages; for example, it can precisely identify the location of a particle in 3D, as well as separate the particles throughout the whole micro canal, all of which is not possible based on experimental results. Also, we built this system entirely with a 3D architecture of PCB, a microfluidic platform, a Bluetooth wireless controller, and a source of power supply integrated all in one microsystem. The whole microelectronic part of the LoC is put on a microelectronic chip made with the CMOS 0.18 um TSMC technology. As for the microfluidic architecture, it was fabricated using both the Sensonit and Lionix processes

Microfluidics and Nanofluidics Handbook

The Microfluidics and Nanofluidics Handbook: Two-Volume Set comprehensively captures the cross-disciplinary breadth of the fields of micro- and nanofluidics, which encompass the biological sciences, chemistry, physics and engineering applications. To fill the knowledge gap between engineering and the basic sciences, the editors pulled together key individuals, well known in their respective areas, to author chapters that help graduate students, scientists, and practicing engineers understand the overall area of microfluidics and nanofluidics. Topics covered include Finite Volume Method for Numerical Simulation Lattice Boltzmann Method and Its Applications in Microfluidics Microparticle and Nanoparticle Manipulation Methane Solubility Enhancement in Water Confined to Nanoscale Pores Volume Two: Fabrication, Implementation, and Applications focuses on topics related to experimental and numerical methods. It also covers fabrication and applications in a variety of areas, from aerospace to biological systems. Reflecting the inherent nature of microfluidics and nanofluidics, the book includes as much interdisciplinary knowledge as possible. It provides the fundamental science background for newcomers and advanced techniques and concepts for experienced researchers and professionals

Manipulation of magnetic microparticles in liquid phases for on-chip biomedical analysis methods

Magnetic microparticles and their application in bioanalytical microfluidic systems have been steadily gaining interest in recent years. This progress is fueled by the comparatively large and long range magnetic forces that can be obtained independently of the fluidic flow pattern. This thesis work presents new approaches for using magnetic microparticles in Lab-on-a-Chip systems. The first approach deals with the design of a magnetic droplet manipulation system and the second combines magnetic particle actuation with integrated optical detection. The applicability of both systems for miniaturized bioanalysis will be shown, demonstrating the potential of magnetic particle based Lab-on-a-Chip systems. The magnetic droplet manipulation system tackles the handling of small liquid volumes, which is an important task in miniaturized analytical systems. The careful adjustment of hydrophilic/hydrophobic surface properties and interfacial tensions leads to the design of a system, where small droplets are manipulated in a controllable fashion. The system's setup permits the direct implementation of bioanalytical protocols and two different procedures are in consequence examined. Based on a commercial laboratory kit, a platform for the on-chip extraction and purification of DNA will be designed. The miniaturized setup allows the user to capture and clean the DNA obtained from a raw cell sample containing as little as 10 cells, which is several orders of magnitude lower than known for macroscopic systems. A similar performance is observed for the colorimetric antibody detection further-on evaluated in the droplet manipulation system, where the small sample volumes permit a significant reduction of the reaction times. With the possibility of concentrating the biomolecules of interest on the particle surface, a sensitive and fast immunosorbent assay can be devised. A further miniaturization is examined in a CMOS system, which combines magnetic actuation and optical detection. The small dimensions of the actuation system allow the manipulation of single magnetic microparticles and the integration of Single Photon Avalanche Diodes (SPADs) enables their optical detection. An innovative detection algorithm permits hereby to distinguish the particles in size and, in combination with a velocity measurement, to evaluate the magnetic properties of the detected particles. In consequence, bioanalysis on a single magnetic particle using fluorescent measurements can be performed, as is shown by preliminary experiments

ECOS 2012

The 8-volume set contains the Proceedings of the 25th ECOS 2012 International Conference, Perugia, Italy, June 26th to June 29th, 2012. ECOS is an acronym for Efficiency, Cost, Optimization and Simulation (of energy conversion systems and processes), summarizing the topics covered in ECOS: Thermodynamics, Heat and Mass Transfer, Exergy and Second Law Analysis, Process Integration and Heat Exchanger Networks, Fluid Dynamics and Power Plant Components, Fuel Cells, Simulation of Energy Conversion Systems, Renewable Energies, Thermo-Economic Analysis and Optimisation, Combustion, Chemical Reactors, Carbon Capture and Sequestration, Building/Urban/Complex Energy Systems, Water Desalination and Use of Water Resources, Energy Systems- Environmental and Sustainability Issues, System Operation/ Control/Diagnosis and Prognosis, Industrial Ecology