Design and realization of an electrophoretron cycler

Polymerase Chain Reaction (PCR) is a powerful enzymatic reaction commonly used to amplify specific sequences of Deoxyribo Nucleic Acid (DNA). Since the introduction of the lab on a chip concept, numerous Continuous Flow PCR cyclers were realized with success at the micro scale. As reducing the reactor size and improving thermal management led to reduced sample volumes, results could be achieved much faster with these CF-PCR cyclers than with common commercial cycler. Furthermore, most of these demonstrated CF-PCRs are nowadays evolving towards high-throughput systems. However, most CF-PCR cyclers require complex manipulations and are not flexible (e.g. fixed number of cycles, and/or only usable for PCR …). The concept of the electrophoretron cycler was introduced and demonstrated at the macro scale in 2001. The present work aims at using this electrokinetic cycler combining electroosmosis and electrophoresis in order to achieve cycling of the DNA species in a micro scale on-chip device, while applying only one potential difference. Even limited by polymers properties, appropriate design of the closed-loop microchannel allows the hydrodynamic effect resulting from mass conservation to drastically improve cycling time and species profile. This result has been justified by appropriate theoretical analysis combined with numerical simulations, while polymers properties have been carefully characterized using experiments, resulting in the first micro scale electrophoretron prototype which has been tested in PCR like conditions

DEVELOPMENT OF FREE-LABEL SENSING IN PLASTIC MICROFLUIDIC PLATFORMS USING PULSED STREAMING POTENTIALS (PSP)

This work deals with the development of a new label-free detection technique called Pulsed Streaming Potential (PSP). Its novelty relies on the adaptation of a classical electrokinetic phenomenon (streaming potential) into a tool which can evaluate molecular interplay in label-free fashion. Implementation of PSP to microfluidic platforms allowed the label-free sensing of binding events to plastic (modified and unmodified) surfaces. It was demonstrated the use of real time PSP in plastic microfluidic platforms for determination of kinetic parameters of the interaction of proteins and plastic surfaces. Moreover, initial change of PSP after adsorption of proteins showed to be proportional to the bulk concentration of proteins and it was used for quantification of Lysozyme in the nanomolar range. Several approaches were studied to manipulate the surface of microfluidic channels in order to improve selectivity of PSP through reduction of non-specific adsorption. These approaches included the fabrication of composite surface of polyacrilic acid (PAA) and polyethylene glycol acrylate (PEGA) on cyclic olefin copolymer microchannels, as well as adsorption of nanospheres on COC-PEGA channels

Heterogeneous 2.5D integration on through silicon interposer

© 2015 AIP Publishing LLC. Driven by the need to reduce the power consumption of mobile devices, and servers/data centers, and yet continue to deliver improved performance and experience by the end consumer of digital data, the semiconductor industry is looking for new technologies for manufacturing integrated circuits (ICs). In this quest, power consumed in transferring data over copper interconnects is a sizeable portion that needs to be addressed now and continuing over the next few decades. 2.5D Through-Si-Interposer (TSI) is a strong candidate to deliver improved performance while consuming lower power than in previous generations of servers/data centers and mobile devices. These low-power/high-performance advantages are realized through achievement of high interconnect densities on the TSI (higher than ever seen on Printed Circuit Boards (PCBs) or organic substrates), and enabling heterogeneous integration on the TSI platform where individual ICs are assembled at close proximity

Industry-supported, and standardized modular platform:interconnecting fluidic circuit board and microfluidic building blocks

The research done is focussed on improving the gap between the number of academic proof of concept microfluidic devices and the number of commercial application. A start is made by analysing the factors that inhibit the commercialization of microfluidics. It turns out there are multiple: their multidisciplinary nature, the need for high volume production, the lack of focus due to their broad applicability. To overcome these inhibiting factors an industry-supported, and standardized modular platform is introduced and supported by the European MFManufacturing project. This platform consists out of two parts, the interconnecting fluidic circuit board and the microfluidic building blocks. This platform overcomes some of the inhibiting factors by using the building blocks. They are usable in multiple system, resulting in higher volumes. The building blocks make designing new systems easier. The design effort can be done in several stages, without the need to redo ever stage for a new system. The standardization of the platform is mainly concerned about interoperability, examples are fixed dimensions for the outside dimensions of the microfluidic building blocks and the locations of the interconnects. A library with building blocks and their characterization was also started, including a pressure sensor, valve and reservoir. Also different types of fluidic circuit board were demonstrated. To be able to effectively design new microfluidic systems, a new computer aided design tool was also developed in the MFManufacturing project.To check how well the new standardized platform performs two systems are designed according to it. An AC coulter counter and a cell culturing platform containing 192 individual culture chambers. The AC coulter counter system demonstrates the possibility of the platform to include electrical connection and mix multiple materials in a single system while maintaining a compact footprint of a credit card size. The cell culturing platform consists out of 3 microfluidic building blocks each containing 64 chamber. The fluidic circuit board has integrated valves to be able to individually activate or deactivate a building block. By using multiplexing in the building blocks and a chip select in the fluidic circuit board, over thousand valves can be controlled by only 16 external lines. Hereby greatly reducing the complexity of the setup. At the end of the MFManufacturing project a new Microfluidic Consortium was formed with members from existing project and new external member. In this new Microfluidic Consortium several workshop have been organized to continue standardization in the microfluidic field

Overview of Large-Scale Computing: The Past, the Present, and the Future

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Development of an autonomous lab-on-a-chip system with ion separation and conductivity detection for river water quality monitoring

This thesis discusses the development of a lab on a chip (LOC) ion separation for river water quality monitoring using a capacitively coupled conductivity detector (C⁴D) with a novel baseline suppression technique.Our first interest was to be able to integrate such a detector in a LOC. Different designs (On-capillary design and on-chip design) have been evaluated for their feasibility and their performances. The most suitable design integrated the electrode close to the channel for an enhanced coupling while having the measurement electronics as close as possible to reduce noise. The final chip design used copper tracks from a printed circuit board (PCB) as electrodes, covered by a thin Polydimethylsiloxane (PDMS) layer to act as electrical insulation. The layer containing the channel was made using casting and bonded to the PCB using oxygen plasma. Flow experiments have been conduced to test this design as a detection cell for capacitively coupled contactless conductivity detection (C⁴D).The baseline signal from the system was reduced using a novel baseline suppression technique. Decrease in the background signal increased the dynamic range of the concentration to be measured before saturation occurs. The sensitivity of the detection system was also improved when using the baseline suppression technique. Use of high excitation voltages has proven to increase the sensitivity leading to an estimated limit of detection of 0.0715 μM for NaCl (0.0041 mg/L).The project also required the production of an autonomous system capable of operating for an extensive period of time without human intervention. Designing such a system involved the investigation of faults which can occur in autonomous system for the in-situ monitoring of water quality. Identification of possible faults (Bubble, pump failure, etc.) and detection methods have been investigated. In-depth details are given on the software and hardware architecture constituting this autonomous system and its controlling software

Study on Optical Properties and Biocompatibility of Different Polymer-Gold Nano-Composite Platforms for Opto-Micro Fluidic Applications

Microfluidic and microphotonic devices have become increasingly effective for diagnostic, clinical, and biochemical applications. Such technologies usually contain polymer materials, as their properties make them highly desirable for sensing possibilities. A useful addition to these materials are gold nanoparticles (GNP), which hold unique localized surface plasmon resonance (LSPR) properties that are affected by their structure, shape, distribution, and their degree of penetration into the surrounding medium. These characteristics, in turn, depend on the thermal history of the sample, that is, the extent and duration of heating of the polymer-GNP systems. In this undertaking, thermally tunable gold-polymer nanocomposite platforms, which have customizable properties, are fabricated for emerging opto-fluidic applications. This is achieved using a thermal convection method using six polymer films: poly (vinyl alcohol) (PVA), SU-82, poly (styrene) (PS), poly (dimethyl siloxane) (PDMS), cyclic olefin copolymer (COC), poly (methyl methacrylate) (PMMA). In order to increase the plasmonic sensitivity of the platforms, the nanocomposites are, subsequently, subjected to heat treatment with incremental heating in the range of 80-2000C. It is found that, among the polymers studied in this work, PVA and SU-82 show the largest shift of the Au LSPR band upon incremental heating as well as the highest plasmonic sensitivity. To test the biocompatibility of these different polymers, tagged antibodies are immobilized on the functionalized polymer films, and then the corresponding antigens are allowed to interact with the antibodies. The results of this work will be helpful in selecting a suitable material for both microfluidic and microphotonic experiments

Integrated polymer photonics : fabrication, design, characterization and applications

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