Berthier J. – Page 3 – TechConnect Briefs

On the behavior of non-Newtonian fluids in microsystems for biotechnology

Berthier J., Le Vot S., Tiquet P., Rivera F., Caillat P., CEA/LETI/MINATEC, FR

In Biotechnology, it is generally the use to calculate and design prototypes of microsystems by considering aqueous or organic liquids that have a spatially uniform viscosity. However, many liquids used in biological applications are at [...]

Sacrificial membranes for serial valving in microsystems

Allain M., Berthier J., Basrour S., Pouteau P., CEA/LETI/MINATEC, FR

Valving is essential to microflow circuits in microsystem technology. Many different types of valves have already been designed. Membranes of sacrificial materials have been studied for one shot valving; however, the new design proposed here, [...]

Silicon die self-alignment on a wafer: stable and instable modes

Berthier J., Grossi F., Di Cioccio L., CEA/LETI/MINATEC, FR

To create advanced Microsystems by 3D integration, die-to-wafer assembly is required to obtain fast and reliable packaging. In order to overcome the main difficulties of current techniques, self-assembly methods are promising due to their serial [...]

On the stability length of fluid/liquid interfaces sustained by microfabricated pillars

Berthier J., Man Tran Van, Jeanson H., Sarrut N., CEA-LETI, FR

We focus here on the transfer and concentration of macromolecules from a flowing carrier fluid to a storage liquid. These liquids are flowing in parallel channels, separated by interfaces sustained by micro-pillars. The two fluids [...]

Modeling microdrop motion between covered and open regions of EWOD microsystems

Berthier J., Clementz Ph., Roux J-M, Fouillet Y., Peponnet C., CEA-LETI, FR

Digital microfluidics is a promising way to manipulate biological targets like DNA, proteins or cells in very small liquid volumes. The advantages of such devices are the use of lesser quantities of costly reagents, better [...]

Mechanical Behavior of Micro-Drops in EWOD Systems: drop extraction, division, motion and constraining

Berthier J., Clementz Ph., Jary D., Raccurt O., Claustre P., Peponnet C., Fouillet Y., CEA-LETI, FR

We present a novel contribution to the design of electrowetting microdevices (EWOD) by using an energy minimization approach. Altough the dynamics of motion of microdrops by electrowetting may be rapid, it is shown that, due [...]

An Analytical Model for the Prediction of Microdrop Extraction and Splitting in Digital Microfluidics Systems

Berthier J., Raccurt O., Clementz Ph., Jary D., Claustre P., Peponnet C., Fouillet Y., CEA-LETI, FR

In the preceding text submitted to Nanotech 2005, we have demonstrated that surface tension is the dominant force on liquid microdrops in EWOD microsystems and that the problem is mostly topological. Minimization of the surface [...]

Dimensioning of a New Micro-Needle for the Dispense of Drugs in Tumors and Cell Clusters

Berthier J., Rivera F., Caillat P., Berger F., CEA-LETI, FR

In medical treatment, there is a constant need to deliver active molecules into targeted cells, but this dispense is often difficult and time consuming. For example, in cancerology, it has been shown that active molecules [...]

Numerical Modeling of Diffusion in Extracellular Space of Biological Cell Clusters and Tumors

Berthier J., Rivera F., Caillat P., CEA-LETI, FR

Biological cluster of cells may be seen as porous media, where the cells are the “solid grains” and the extracellular space (ECS) the “pores”. It is often the case in dense clusters of cells that [...]

Modeling of the Kinetics of Capture of Pathogens Enhanced by a Marangoni Flow

Pham P., Achard J.L., Berthier J., Ginot F., CEA-LETI, FR

Binding of targetted biomolecules, pathogens or analytes on a reactive surface is commonly used for biodiagnostic systems. However the process is slow and inefficient if one relies only on molecular diffusion to transfer the analytes [...]