Resonant biosensors are known for their high accuracy and high level of miniaturization. However, their fabrication costs prevent them from being used as disposable sensors and their effective commercial success will depend on their ability to be reused repeatedly. Accordingly, all the parts of the sensor in contact with the fluid need to tolerate the regenerative process which uses different chemicals (H₃PO₄, H₂SO₄ based baths) without degrading the characteristics of the sensor. In this paper, we propose a fluidic interface that can meet these requirements, and control the liquid flow uniformity at the surface of the vibrating area. We study different inlet and outlet channel configurations, estimating their performance using numerical simulations based on finite element method (FEM). The interfaces were fabricated using wet chemical etching on Si, which has all the desirable characteristics for a reusable biosensor circuit. Using a glass cover, we could observe the circulation of liquid near the active surface, and by using micro-particle image velocimetry (μPIV) on large surface area we could verify experimentally the effectiveness of the different designs and compare with simulation results.

We describe in this work an advanced microfluidic chip for the capture of bioanalyte on the surface of droplets arranged in a dense array. We show the procedure for generating, functionalizing, and arranging the droplets inside the device for capturing a specific bioanalyte. Then, we demonstrate the capacity of the array to capture analyte from a cross-flowing liquid, using a biotin/streptavidin model. The paper also proposes to use the droplets array, after integration with acoustic detection, as a regenerable detection interface for bioanalyte sensing. We model the arrangement of droplet in dense array and show that they present a larger effective capture surface and shorter capture distance than standard flat surface biosensor of the same footprint. As the droplets can be easily evacuated and replaced inside the device analysis chamber, the proposed biosensor would allow biointerface regeneration and chain measurement without dismounting the device.

This work reports on the design, the modeling, the simulation, the integration strategy and the preliminary test results of a new variable capacitor using large variation of permittivity obtained by tuning the density of oil-in-water droplet produced with a microfluidic circuit.

Advanced therapy medicinal products (ATMPs), especially effective against cancer, remain costly due to their reliance on genetically modified T cells. Contamination during production is a major concern, as traditional quality control methods involve samplings, which can themselves introduce contaminants. It is therefore necessary to develop methods for detecting contamination without sampling and, if possible, in real time. In this article, we present a white light spectroscopy method that makes this possible. It is based on shape analysis of the absorption spectrum, which evolves from an approximately Gaussian shape to a shape modified by the 1/λ component of bacterial absorption spectra when contamination develops. A warning value based on this shape descriptor is proposed. It is demonstrated that a few hours are sufficient to detect contamination and trigger an alarm to quickly stop the production. This time-saving should reduce the cost of these new drugs, making them accessible to as many people as possible. This method can be used regardless of the type of contaminants, provided that the shape of their absorption spectrum is sufficiently different from that of pure T cells so that the shape descriptor is efficient.