Etertec HQ-6100 dry film photoresist was used in this work to fabricate soft-lithography masters applied to microfluidic applications. We demonstrated that the use of this photoresist was a convenient alternative to conventional microfabrication approaches based on DRIE and liquid photoresists for fast-prototyping of microfluidic structures. Our method was at least two times faster than conventional processes and required limited investment for equipments. Finally, this approach was applied to the design and fabrication of microfluidic networks used for gradient generation in bulk solution.

The proposed HDR-BT phantom and instrumented applicator have been tested and their main characteristics have been evaluated. These systems perform unsupervised measurements and analysis without prior treatment plan information. They allow independent verification of dwell position and time with accuracy of measurements comparable with other similar systems reported in the literature.

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This paper presents a buried quad p-n junction (BQJ) photodetector fabricated with a HV (high-voltage) CMOS process. Multiple buried junction photodetectors are wavelength-sensitive devices developed for spectral analysis applications where a compact integrated solution is preferred over systems involving bulk optics or a spectrometer due to physical size limitations. The BQJ device presented here is designed for chip-based biochemical analyses using simultaneous fluorescence labeling of multiple analytes such as with advanced labs-on-chip or miniaturized photonics-based biosensors. Modeling and experimental measurements of the spectral response of the device are presented. A matrix-based method for estimating individual spectral components in a compound spectrum is described. The device and analysis method are validated via a test setup using individually modulated LEDs to simulate light from 4-component fluorescence emission.

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This paper presents an alternative approach to create low-cost and patternable carbon electrodes suitable for microfluidic devices. The fabrication and the electrochemical performances of electrodes made of Polydimethylsiloxane doped with commercially available carbon black (C-PDMS) are described. Conductivity and electrochemical measurements performed on various carbon to PDMS ratios showed that electrodes with suitable electrochemical properties were obtained with a ratio of 25 %.Keywords: Carbon electrodes, PDMS, Microfluidics, Voltammetry, Plasma treatment DOI: 10.1002/elan.201000321 Carbon is a widely used material for electrochemistry due to inherent advantages as a low-cost, quite inert material and its wide electrochemical potential window [1]. Such electrodes are for example very well suited for most biological assays but their patterning is an issue that has to be addressed for their chip-based applications. Various approaches were developed to achieve such integration as the insertion of carbon fibres [2], screen printing carbon paste [3][4][5], micromolding carbon ink [6], pyrolysis of photoresist [7,8] and by doping photoresist with carbon particles [9]. The last solution is very versatile in obtaining various electrode geometries but suffers from the complexity of the doped photoresist preparation. Moreover, the temperature required for carbonaceous electrodes obtained from pyrolysis of photoresist layer is beyond the thermal budget of many low temperature polymer-based processes and requires specific substrates such as Si. Despite the interest of combining carbon inks with softlithography, such method still suffers from an inherent complexity for electrode integration into microfluidic devices. Indeed, the bonding of electrodes on the device material is a critical issue which is alternatively obtained by applying a small pressure between the two substrates.Here, we present a method to fabricate low-cost and patternable C-PDMS electrodes and their preliminary electrochemical performances were evaluated.Poly(dimethylsiloxane) (PDMS) is a very attractive material to fabricate microfluidic structures and is widely used in the lab-on-a-chip community. Recently, it was shown that this elastomer can be made conductive by doping it with carbon or silver nanoparticles [10,11] and carbon nanotubes [12]. Carbon doped PDMS (C-PDMS) was used to fabricate strain gauge [13] and finger print sensor [14]. Moreover, recent studies reported the integration of C-PDMS in microfluidic systems to achieve capacitive detection of droplets [15], heating in microfluidic environment [16], and also the fabrication of microfluidic components by controlling electrorheological fluids [16]. However, to our best knowledge, electrochemical characterization of doped PDMS electrodes was never reported in literature.Composite electrodes such as carbon paste electrodes are widely used in electrochemical detection as they exhibit a small capacitive current and a faradic current proportional to the total surface area of the ele...

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