Search results for "microsystem"
showing 10 items of 13 documents
An Alginate/Cyclodextrin Spray Drying Matrix to Improve Shelf Life and Antioxidant Efficiency of a Blood Orange By-Product Extract Rich in Polyphenol…
2017
Alginate and β-cyclodextrin were used to produce easily dosable and spray-dried microsystems of a dried blood orange extract with antidysmetabolic properties, obtained from a by-product fluid extract. The spray-dried applied conditions were able to obtain a concentrate dried extract without the loss of AOA and with TPC and TMA values of 35–40% higher than that of the starting material. They were also effective in producing microparticles with 80–100% of encapsulation efficiency. The 2% sodium alginate was capable of improving the extract shelf life, while the beta-cyclodextrin (1 : 1 molar ratio with dried extract) prolonged the extract antioxidant efficiency by 6 hours. The good inhibition…
A low power interface circuit design for a CMOS based smart optical sensor
2012
In this paper, a CMOS interface circuit as part of an optical sensor-based microsystem for pH monitoring applications is presented. The proposed circuit is capable of processing a voltage signal produced by the light transducer and generating 8-bit digital outputs representing the color information (i.e. wavelength). A resolution of 8 different colors has been achieved as a proof of concept and can easily be extended to a higher number of colors without a major modification in the architecture. The proposed interface circuit is a mixed-signal solution that consists of analog as well as digital building blocks along with a light transducer. It can be used as a portable and non-intrusive opti…
DE.DU.ENER.T. project: A prototype of a sustainable energy microsystem
2016
The paper presents a prototype of a microsystem for the integration and the optimal management of renewable energy sources in order to attain a reduction of the total energy consumption of a not residential building. The system composed by the building and the prototype is an energy sustainable microsystem and is located in Italy in the city of Valderice. The microsystem has been conceived in the ENPI (European Neighborhood and Partnership Instrument) cross-border cooperation Italy - Tunisia 2007-2013 DE.DU.ENER.T. (Le DEveloppement DUrable dans la production ENERgetique dans le Territoire) research project framework. In the paper the purposes of the DE.DU.ENER.T. project are presented and …
Quasi-digital conversion for resistive devices: application in GMR-based IC current sensors
2013
Resistive devices, including sensors, are used in a huge range of applications within different scenarios. When a complete system is considered, a quasi-digital output is often recommendable. If the conversion is operated at device level, some problems such as noise disturbs, insertion losses and so on, can be reduced. In this work, we describe a resistance-tofrequency (R-f) converter with a suggested application in low current monitoring by means of GiantMagnetoResistance (GMR) sensors. Specific devices have been designed and microfabricated. The system has been tested by means of discrete components with a PCB. The complete microsystem monolithic integration in a standard CMOS technology …
Engineering Polymer Microparticles by Droplet Microfluidics
2013
Capillary-based flow-focusing and co-flow microsystems were developed to produce sphere-like polymer microparticles of adjustable sizes in the range of 50 to 600 μm with a narrow size distribution (CV < 5%) and different morphologies (core-shell, janus, and capsules). Rod-like particles whose length was conveniently adjusted between 400 μm and few millimeters were also produced using the same microsystems. Influence of operating conditions (flow rate of the different fluid, microsystem characteristic dimensions, and design) as well as material parameters (viscosity of the different fluids and surface tension) was investigated. Empirical relationships were thus derived from experimental data…
Synthesis of polymer materials for use as cell culture substrates
2007
International audience; Up to today, several techniques have been used to maintain cells in culture for studying many aspects of cell biology and physiology. More often, cell culture is dependent on proper anchorage of cells to the growth surface. Thus, poly-L-lysine, fibronectin or laminin are the most commonly used substrates. In this study, electrosynthesized biocompatible polymer films are proposed as an alternative to these standard substrates. The electrosynthesized polymers tested were polyethylenimine, polypropylenimme and polypyrrole. Then, the adhesion, proliferation and morphology of rat neuronal cell lines were investigated on these polymer substrates in an attempt to develop ne…
Monolithic integration of Giant Magnetoresistance (GMR) devices onto standard processed CMOS dies
2014
Giant Magnetoresistance (GMR) based technology is nowadays the preferred option for low magnetic fields sensing in disciplines such as biotechnology or microelectronics. Their compatibility with standard CMOS processes is currently investigated as a key point for the development of novel applications, requiring compact electronic readout. In this paper, such compatibility has been experimentally studied with two particular non-dedicated CMOS standards: 0.35 μm from AMS (Austria MicroSystems) and 2.5 μm from CNM (Centre Nacional de Microelectrònica, Barcelona) as representative examples. GMR test devices have been designed and fabricated onto processed chips from both technologies. In order …
Muscular MEMS—the engineering of liquid crystal elastomer actuators
2016
A new class of soft-matter actuator, the liquid crystal elastomer (LCE), shows promise for application in a wide variety of mechanical microsystems. Frequently referred to as an 'artificial muscle', this family of materials exhibits large actuation stroke and generates considerable force, in a compact form which may easily be combined with the structures and devices commonly used in microsystems and MEMS. We show here how standard microfabrication techniques may be used to integrate LCEs into mechanical microsystems and present an in-depth analysis of their mechanical and actuation properties. Using an example from micro-optics and optical MEMS, we demonstrate that their performance and fle…
A MEMS array-type Mirau interferometer for swept-source OCT imaging with applications in dermatology
2017
In the frame the European project VIAMOS (www.viamos.eu) we developed a microsystem based on Mirau interferometry and applied for optical coherence tomography (OCT) imaging of living tissues. The objective is to benefit from advanced MOEMS technologies, enabling a new generation of miniature and low-cost instruments using the concept of the swept-source OCT (SS-OCT) microsystem based on spectrally tuned Mirau interferometry, into which a doublet of microlens matrices (4×4) and a wafer of movable reference mirrors are included, building the active Mirau interferometer.
Chromatographic Air Analyzer Microsystem for the Selective and Sensitive Detection of Explosive-related Compounds
2014
Abstract The detection of explosives and explosive-related compounds is of major importance for the monitoring of explosive- contaminated sites. Current methods need to become cheaper and portable while maintaining a high sensitivity and selectivity level. In that sense, a silicon micro-analytical platform consisting of a three-dimensional micro-preconcentrator based on a hydrophobic zeolite, coupled to a silicon spiral micro-column was built. A chemical gas sensor acted as a miniaturized gas detector. This system allowed selective detection of orthonitrotoluene (ONT), an explosive-related compound at the sub-ppm level in the presence of toluene and moisture.