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Research on microfluidic devices for biological analysis has progressed sufficiently to be developed into point-of-care diagnostics products. The goal of this thesis is to improve multiple aspects of capillary-driven microfluidic devices. In particular, the objective is to provide devices with a fast time to result, that are simple to use (one-step), that can be portable, that accept a variety of samples, that operate reliably, that provide a range of detection signals, that are mass manufacturable at lost cost, and that are able to detect medically relevant biological molecules. First, we survey the evolution of microfluidic research into portable medical diagnostic devices. By looking at several gaps and opportunities in current medical diagnostics, we provide an overview of research topics that have the potential to shape the next generation of point-of-care diagnostics. Specifically we explain technologies in the order of sample interacting with different components of a device. We investigate the materials, surface treatments, sample processing, microfluidic elements (such as valves, pumps and mixers), receptors and analytes and the integration of these components into a device that might conceivably leave the laboratory for the hands of consumers. The knowledge of what is important in a point-of-care diagnostics device was used to develop a proof of concept. One of the main challenges is to make microfluidics easy to use by incorporating reagents and microfluidic elements. We integrated a number of functional elements on a chip such as a sample collector, delay valves, flow resistors, a deposition zone for detection antibodies (dAbs), a reaction chamber sealed with a polydimethylsiloxane (PDMS) substrate, and a capillary pump and vents. We further incorporated capture antibodies (cAbs), detection antibodies (dAbs) and analyte molecules for making one-step immunoassays. The integrated microfluidic chip requires only the addition of sample to trigger a sequence of events controlled by capillary forces to detect C-reactive protein (CRP), a general inflammation and cardiac marker, at a concentration of 1 ng mL-1 within 14 min using only 5 µL of human serum. The proof-of-concept is extended to easily modify several assay parameters such as the flow rates and the volumes of samples for tests, and the type of reagents and receptors for analytes. The multiparametric microfluidic chip is capable of analyzing 20 µL of human serum in 6 parallel flow paths in a range of flow rates with filling times from 10 minutes to 72 minutes. The asymmetric release of dAbs in a stream of human serum is compensated by a Dean flow mixer. Sample is equally split into 6 reaction chambers connected to flow resistances that vary flow rates, and the kinetics of capture of analyte-dAb complexes. The increased incubation time leads to a fourfold increase in detection signal in the reaction chamber with the longer incubation time. Furthermore, integrating reagents and controlling their release is essential for simple and accurate point-of-care diagnostic devices. We developed reagent integrators (RIs) to release small amounts of dried reagents (ng quantities and less) into microliters of sample. Typical RIs are composed of an inlet splitting into a central reagent channel, with a high hydraulic resistance, and two diluter channels. Reagents spotted in the central channel reconstitute in sample during filling and merge at the end of the RI with a dilution factor corresponding to the relative hydraulic resistance of the channels forming the RI. RIs are simple to integrate in lateral flow assays and provide a great degree of control over reagent integration and dissolution. Finally, the one-step capillary-driven microfluidic chips have the ability to not only detect a variety of proteins, but also to detect nucleic acids for molecular diagnostics. These devices, especially if manufactured in low cost plastic and used with portable fluorescence readers, have the potential to identify a wide variety of health conditions and to enable truly decentralized medical diagnostics.

Since stem cells have the unique ability to produce more of themselves (i.e. to "self-renew") and to generate specialized tissue cells, they are an ideal source of cells for regenerative medicine and in vitro tissue models. In order to fully exploit this potential, we have to better understand the mechanisms that regulate stem cell behavior at a single cell level. However, current in vitro methodologies to study single cells are limited by their throughput, do not afford to distinguish the fate of daughter cells or track the progeny of a single cell over long time periods. This thesis addresses these shortcomings by developing miniaturized devices to handle and analyze single live stem cells. To this end, a micro-structured platform was first established that consisted of miniaturized wells with diameters of 100 µm that were arranged in a regular grid. Single hematopoietic stem cells (HSCs) were then seeded into these "microwell arrays" and, since the HSCs could not leave the microwells, they could be tracked over many days, and their dynamics and proliferation rates could be studied. However, in order to analyze the daughter cells of these single HSCs individually, the daughter cells have to be physically separated by micromanipulation. For this purpose, a microdevice was developed to reliably manipulate single cells using hydrodynamic single cell trapping. This platform was thoroughly characterized using computational simulations combined with particle flow velocimetry and live-cell time-lapse microscopy. The optimization of design parameters towards increasing trapping efficiency ensured a nearly perfect efficiency of single cell trapping (97%) and a successful re-capture of daughter cells generated by dividing mother cells. Furthermore, it was demonstrated that cell trapping under very low flow is sufficiently gentle to enable long-term cell trapping in the microfluidic environment. To identify and track captured cells in these microfluidic single cell traps, automated image analysis tools were developed. A reliable and fast algorithm was generated to identify the borders of microchannels that were indicative for the position of single cell traps. These detected edges were used to individualize the single cell traps with a sub-pixel resolution such that it was possible to segment single HSCs on the chip by thresholding. Accordingly, single HSCs were discovered with efficiencies as high as >95%, allowing the automated tracking of microfluidic single cell trapping, as well as the detection of cell cycle phases of trapped single HSCs engineered with dual fluorescence reporter system marking G1 and S/G2-M. To actively micromanipulate single cells for downstream cell-fate analyses, on-chip valves were integrated on the microfluidic platform to precisely control the direction of medium flow in the microfluidic channels. This approach enabled a proof-of-concept study to demonstrate a more complex single cell manipulation: Cells were first captured in single cell traps and transferred into a culture chamber for clonal expansion. Subsequently, the progeny of these single cells was removed from the culture chamber and trapped in a series of single cells traps. Importantly, since these traps could be addressed individually, a reliable physical separation of the daughter cells was achieved. To enable individual analyses of these separated daughter cells, the last aim of this thesis was to interface a microfluidic chip with standard multititer plates in order to efficiently recover the cells or the cDNA of the single cell generated on-chip from extracted mRNA. For this purpose, the bottom of the chip was equipped with an array of access holes that matched the layout of a 1536-well plate. These access holes were linked to a single cell trap via an analysis chamber, where the HSCs were lysed and their mRNA was reverse transcribed using bead-coupled primers. In this vain, the obtained cDNA was coupled to these beads that could then removed from the chip into a 1536-well by centrifugation. These beads could then be analyzed using standard bench-top PCR machines. In conclusion, this thesis presented several microfluidic modules to handle and analyze single stem cells in high-throughput. In a proof-of-concept study, these modules were applied to automatically capture single cells, culture them, and subsequently separate the daughter cells for downstream cell-fate analyses, thereby greatly enhancing the throughput compared to manual micromanipulation. During the development of this system, it became apparent how crucial reliable and gentle cell handling is to perform complex experimental tasks with live cells on microfluidic chips. The further integration of such microfluidic modules into multi-functional lab-on-a-chip devices will open the door to experimental paradigms previously not imaginable and promises novel insights in stem cell biology.

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.

This thesis reports on the development of technologies and methods for a microfiuidic device for continuous pressure-driven flow-injection analysis. Chip based, pressure-driven liquid chromatographic (LC) systems are often avoided due to the difficulties encountered when it comes to flow control. The complexity involved precludes, for the time being commercializable, on-chip integration of valves and micropumps for microfluidic devices. However, LC is still the workhorse analytical method in most laboratories for small molecule analysis. There is a growing demand from the industry to have LC sensors being capable of direct sampling on the production lines, hence obviating the time-consuming detour to the lab. As a possible solution to this demand, the concept of a chromatographic device is presented. It incorporates continuously flowing analyte and mobile phase streams and is capable of aliquoting samples from meso scale flows. Plugs are injected by momentarily change the flow distribution within the microfluidic channels by exploiting the method of gated flow injection in pressure-driven microchannels. The theoretical concept and experimental evidence is shown for two possible implementations; thermal plug injection through local homogenous bubble nucelation and pressure-drop plug injection. For the microfabricated device, a sol-gel technique is adapted to coat the open-tubular column walls with a C8 stationary phase. Multi-compound phenolic solutions and vitamins are successfully separated to characterize the performance and limits of the chromatographic columns. The last chapter of this work introduces the concept of size-exclusion enhanced, open-tubular chromatography (SOHS) on chip, where a porous column wall is excluding larger molecules and thus increases the separation power of the hydrodynamic separation generated through the parabolic flow profile of the pressure driven flow. The encouraging results are very promising for future applications such as polymer separations or DNA separation.

We developed a new non-invasive integrated microsystem for electrophysiological measurements on Xenopus laevis oocytes. The Xenopus oocyte is a well-known expression system for various kinds of ion channels that are of potential interest for drug screening. In the traditional "Two Electrode Voltage Clamp" (TEVC) method, delicate micromanipulation is required to impale an oocyte with two microelectrodes. In our system, a non-invasive electrical access to the cytoplasm is provided by permeabilizing the cell membrane with an ionophore (e.g. nystatin). Unlike for the classical patch-clamp or "macropatch" techniques, this method does not require removal of the fibrous vitelline membrane. Cell handling is significantly simplified, resulting in more robust recordings with increased throughput. Moreover, because only part of the oocyte surface is exposed to reagents, the required volume of reagent solutions could be reduced by an order of magnitude compared to the TEVC method. In a second part of this work, a rapid fluidic exchange system was implemented on-chip to allow recording of fast kinetic events of exogenous ion channels expressed in the cell membrane. Reducing fluidic exchange times of extracellular reagent solutions is a great challenge with these large millimeter-size cells. Fluidic switching is obtained by shifting the laminar flow interface in a perfusion channel under the cell by means of integrated poly-dimethylsiloxane (PDMS) microvalves. Reagent solution exchange times down to 20 ms have been achieved. An on-chip purging system allows to perform complex pharmacological protocols, making the system suitable for screening of ion channel ligand libraries. The fabrication process for this disposable microchip, based on PDMS micromolding, is cost-efficient and simple. Moreover, an innovative integration of agar gel-based reference electrodes was developed. A conductive liquid junction is injected by capillary force filling of suitable microchannels, overcoming the problems encountered with the integration of Ag/AgCl thin film or wire reference electrodes. We tested this new microdevice by performing electrophysiological measurements on oocytes expressing the human Epithelial Sodium Channel (hENaC). Transmembrane currents could be recorded with a large signal-to-noise ratio. The performance of the integrated rapid fluidic exchange system was demonstrated by investigating the self-inhibition of hENaC. Our results show that the response time of this ion channel to a specific reactant is about one order of magnitude faster than estimated with the traditional TEVC technique. We conclude that this new microdevice has high potential for improved electrophysiological investigations with oocytes in the field of pharmacology and toxicology.

Since the introduction of the of Micro Total Analysis Systems concept in 1990, important progress in microfluidic analytical systems has been realized. In many cases, microfluidic systems have shown improved analytical performances over classical methods, while consuming small amounts of sample and reagents, and strongly reducing analysis time. In this thesis, we propose to explore two important topics in analytics in the microchip format: (i) Capillary electrophoresis (CE) on-chip, where we will focus on pressure-based sample injection techniques and (ii) the isolation and quantification of biological molecules, like antibodies, using magnetic nanoparticles as support in a sandwich immunoassay. After a general introduction, we will introduce the theoretical concepts for understanding our work in CE on-chip, followed by the description of the magnetism applied to the manipulation of magnetic nanoparticles in a microchannel. The state-of-the-art of the injection techniques in a CE microchip and the utilization of microfluidic chips for immunoassays will be introduced, followed by the presentation of two intensively used microfabrication techniques: (i) the powder blasting micro-erosion process for the realization of CE microchips, and (ii) deep reactive-ion etching for the microfabrication of microfluidic chips used for the retention of magnetic nanoparticles. As main results of this thesis, we develop a novel and promising concept of pressure-based injection in a CE microchip, where the sample is flowing continuously through the microchip using a single potential that is constant in time, and injected by a pressure pulse in less than one second. Then, we will introduce a new and original concept to retain superparamagnetic nanoparticles in a microfluidic chip, using a microchannel with periodically enlarged sections. We use this retention technique for the detection and quantification of monoclonal antibodies spiked in cell culture medium or directly obtained from the production of a cell culture. Thereby, we perform a complete on-chip sandwich immunoassay, while using only nanoliters of sample and reagents. Finally, we will conclude the thesis by giving an outlook of the expected future developments of our work and propose potential new applications in other area of microfluidic analytical microsystems.

This thesis mainly deals with the integration of a microfluidic system for the extraction of micrometric and submicrometric particles from a solution. Traditional methods take from several minutes to hours to separate particles from a solution. Microfluidics allow for a more rapid separation, and in addition provide a way to control the duration of the exposition of the particles to a specific reagent. In the first device proposed in this dissertation (called simple exchanger) a microchannel carrying the particle solution overlaps over a short distance with a channel carrying the reagent. In this region the particles are pushed from one solution to the other by dielectrophoretic forces. They are created by an array of microelectrodes patterned on the side of the channel. Diffusion across the interface between the solutions causes molecules from the reagent stream to pollute the particle solution (and inversely). This effect is minimized by increasing the flow velocity in the overlap region. The maximum velocity applicable as well as diffusive mixing and a biochemical application of the device are presented in a first part. In a second part, new designs for the exchanger are proposed in order to prevent diffusive mixing. The first design relies on a massive enlargement of the channel as well as an intermediate buffer flow to keep the destination solution clean. The enlargement diminishes the relative effect of diffusion; the buffer flow "collects" the diffused molecules and is discarded. A second scheme relies on electrophoretic forces to pull charged reagents against diffusion, thereby decreasing diffusive mixing. In a final chapter a microfluidic device based on simple exchangers is used to probe the aggregation of nanoparticles to a biological target. Thanks to a well-controlled flow velocity in the channel and the given channel length the duration a single target is exposed to a nanoparticle solution is known. By exposing targets for different durations it is possible to follow the aggregation kinetics of the nanoparticles. This measurement is carried out for yeast cells and carboxylated nanoparticles. A Brownian dynamics simulation is finally used to outline a promotion of the aggregation due to the microchannel format. In the future, these devices could be used for various applications in the biotechnological domain, where a well-controlled, short duration of exposure of a small particle to a chemical is required.

Low temperature co-fired ceramic (LTCC) technology has attracted remarkable attention in fabrication of sensors and micro-fluidic devices in the last decade. Although structuring planar LTCC foils, which are processed and screen-printed with thick-films, seems straight forward, major problems are encountered once basic sensor features such as cavities and micro-channels are desired within the sensor module. Therefore, this study aims to accomplish two major tasks: development of an advanced technique for fabrication of well-defined and integrated cavities in LTCC and production of novel sensors by using new design parameters and compatible materials systems. Concerning the former objective, we developed graphite-based sacrificial (GB) pastes, which was screen-printed on LTCC, stacked with additional layers and fired. Cavities were formed by removal of sacrificial pastes during different stages of firing: GB was oxidized during sintering of the LTCC module. We selected membrane with inlet and outlet channels as our model device to study the oxidation kinetics of the GB paste as a function of graphite particle size, paste formulation, heating rate, channel dimensions and LTCC open-pore closure behavior and its effects on the membrane features. We found that higher heating rates (> 2.5 °C/min) shifted the oxidation of the paste to higher temperature as expected, whereas lower rates resulted in burnout and LTCC densification at lower temperatures, changing the cavity from a swollen to sagged structure, respectively. Channel dimensions were also found to have a direct influence on membrane swelling such that wider (400 µm) and thicker (> 70 µm of printed paste) channels permitted increased oxygen intake and played the major role in oxidation of the paste, after the closure of LTCC open porosity. We produced membranes within a diameter range of 7-18 mm and well-defined spacing of 13 to 100 µm. Displacement of largest membranes, which can be used as sensitive pressure sensors at sub-20 mbar range, were characterized in terms of applied pressure and membrane swelling. A hysteretic behavior of membrane displacement was observed as a function of swelling, which was absent in case of relatively flat membranes. In the second part of the thesis, fabrication of novel, LTCC-based sensors as an alternative to alumina-based ones was covered. Promising device applications were realized using distinctive properties of LTCC such as low thermal conductivity (an order of magnitude lower than alumina), design flexibility, fine substrate thicknesses (40 µm), lower elastic modulus, etc. Thus, we demonstrated three LTCC-based sensors detecting gas viscosity, force and inclination. Physical principle, materials selection, fabrication procedure and performance of these sensors were explained in detail. The materials compatibility, which is one of the utmost important parameters to assure the quality and the performance of the sensors, was discussed by using various materials characterization techniques and instruments. Differential shrinkage between LTCC tape and thick-film components and the process-dependent-tape shrinkage were found to be the major challenges, which also present the main boundaries of this technology today. In order to avoid the former problem, we modified thick-film terminations by mixing with network-forming additives such as quartz so that its shrinkage behavior was matched to LTCC. This facilitated utilization of thinner LTCC substrates, which is one of the figure of merits, for improved force sensing. The shrinkage of the sensor module, on the other hand, was compensated by manipulating design parameters in light of observed dimensional changes. Finally, future perspectives for structuring LTCC are presented, where an alternative technique to GB pastes is presented: mineral-based sacrificial pastes. In spite of similarity to GB pastes in processing conditions and parameters, these new pastes are formulated by a mixture of high and low melting temperature mineral (CaO) and glass (B2O3), respectively, where a consolidated state is formed that is etched by acid after firing. It was observed that the technique results in well-defined spacing and efficient removal characteristics. On the other hand, shrinkage mismatch to that of LTCC remains a problem.

We developed a space and time adaptive method to simulate electroosmosis and mass transport of a sample concentration within a network of microchannels. The space adaptive criteria is based on an error estimator derived using anisotropic interpolation estimates and a post-processing procedure. In order to improve the accuracy of the numerical solution and to reduce even further the computational cost of the numerical simulation, a time adaptive procedure is combined with the one in space. To do so, a time error estimator is derived for a first model problem, the linear heat equation discretized in time with the Crank-Nicolson scheme. The main difficulty is then to obtain an optimal second order error estimator. Applying standard energy techniques with a continuous, piecewise linear approximation in time fail in recovering the optimal order. To restore the appropriate rate of convergence, a continuous piecewise quadratic polynomial function in time is needed. For this purpose, two different quadratic functions are introduced and two different time error estimators are then derived. It turns out that the second error estimator is more efficient than the first one when considering our adaptive algorithm. Thus, using the second quadratic polynomial, an upper bound for the error is derived for a second model problem, the time-dependent convection-diffusion problem discretized in time with the Crank-Nicolson scheme. The corresponding space and time error estimators are finally used for the numerical simulation of mass transport of a sample concentration within a complex network of microchannels driven by an electroosmotic flow and/or by a pressure-driven flow. Numerical results presented show the efficiency and the robustness of this approach.

A major problem in traditional cell culture methods, such as Petri dishes and culture flasks, is the very simplified artificial environment around the cells. Traditional cell culture methods lack features of the native cell niche, such as gradients and cell organization. This lack probably explains why pharmaceutics against the neurodegenerative Alzheimer's disease successfully stop the propagation of the disease in the Petri dish, but fail so far in clinical trials. This thesis intends to improve cell culture methods for neuroscience research related to neural developmental questions and neurodegenerative diseases. As the cortex is the main part in our brain, related to memory, emotions and perception, this thesis does focus on cell culture tools and protocols for primary cortical neurons. Currently, dissociated neurons are cultured in pure or co-culture of neural and non-neural cells, but structuring elements and controlled gradient formation is missing. The first part of this thesis discusses different studies that implicate environmental components for neural cells in their native neural cell niche. We will establish a generic neural cell niche, which consists of different neural and non-neural cells, a structured 3D environment, molecular gradients and oriented neurite networks, in a nutshell. Additionally, a simplified model of the generic neural cell niche is introduced that is implemented in a microfluidic base cell culture tool. This novel artificial neural cell niche will provide cell layer structure in 3D and local control of molecular gradients at the microscale. We will use microfluidic technology to integrate missing features in cell culture techniques for primary cortical neurons. The microfluidic device will consist of three parts: (1) a main cell culture channel that is used to organize neural cells in 3D hydrogel layers, side-by-side; (2) parallel perfusion channels to mimic nutrient supply and to control stable gradient formation, (3) interconnecting microchannels, called junction channels, that separate perfusion driven molecular transport from diffusive molecular transport. The perfusion channels are connected to device-incorporated reservoirs that allow maintenance of stable molecular gradients based on perfusion and diffusion without the use of peristaltic or syringe pumps. By injecting cortical neurons entrapped in an agarose-alginate solution in the microfluidic device, we generated 3D micropatterned neural cell layers with stable gradients perpendicular to the layer orientation. We demonstrated neurite outgrowth behavior until three weeks in culture. The application of different cell organization patterns revealed an influence of the pattern on the cell culture response. Using neurotrophic gradients of nerve growth factor (NGF) and nutrient supplements (B27), we showed that neurite guidance and synapse formation followed synergistic NGF/B27 gradients. We found that the gradient induced effects are very sensitive to changes in the environmental structure, such as the cell layer organization. Using a gradient of a phosphatase inhibitor, okadaic acid, we generated locally diseased states of the protein Tau in both 2D and 3D micropatterned neural cell cultures. The diseased form of Tau, hyper-phosphorylated Tau, is a major hallmark of Alzheimer's disease. For the first time, local formation of hyper-phosphorylated Tau was demonstrated to affect a defined cell population in a compartmentalized 2D or 3D neural cell culture. Our results revealed that the propagation mechanism of this Alzheimer's diseased lesion is determined through the formation of the 2D or 3D environment. We think that this new neural cell culture tool has the potential to answer biological questions related to environmental and structural parameters involved in the formation of the cerebral cortex and in the propagation of neurodegenerative diseases. Future studies in modern neuroscience research can now better investigate the effect of gradient parameters such as the slope, average concentration or gradient profile on cell culture and disease propagation in a controlled manner. Furthermore, the influence of cell patterns in 2D and 3D is addressed with the ability to modify cell position, density and type at the microscale. The local formation of neurodegenerative disease lesions in a micropatterned neural cell culture is generic, which makes the integration of other neurodegenerative disease models, such as Parkinson's disease, Amyotrophic lateral sclerosis or Huntington's disease, possible.

Nowadays, manipulation of liquids in miniaturised environments finds applications in many fields in biology and medicine such as diagnostics, toxicity analysis, drug delivery and so on. In those domains, the use of disposable devices has the great advantage of removing any surface contamination which could results in device malfunction. In this context, the present work revolves around the use of a thermoexpandable material, composed of expandable beads in an elastomeric matrix, used as actuator for liquids. This material is expandable only once, providing a good actuation for disposable devices. It also allows to keep the material inflated without additional energy input. This thesis has three main goals: understanding the expansion properties of this material through characterisation and modelling, proposing implementation of the heating source, and investigating possible applications. Characterisation of the material reviews its capability to create movement. The two main parameters characterised are the volumetric expansion of the material and the pressure it can provide. To better understand those behaviours, a morphological study of Expancel® beads is also undertaken. Expansion of the composite is then theoretically modelled to provide a tool for future designs. The following part of this thesis focuses on solutions to implement the material for liquid actuation. Before this investigation, the main solution used to heat the material was the resistive heating of copper tracks on a circuit board. Here, alternative solutions are provided such as the use of clean room facilities, screen-printing and polymeric conductors. The pros and cons of the proposed solutions are stated in a way to allow the reader to choose the best option for his application. Finally, some applications of this actuation system are implemented and tested to highlight the limitations and advantages of this technology when put into application.