The observation of the flow of red blood cells in the device designed by Magalie Faivre takes place in the L2 biotech space of the INL, a class 2 biology laboratory. The making of this transportable device is done in another room of the INL, called the White Room. The objects made in this space are of the order of micrometers, with sizes comparable to those of a grain of dust or pollen. The dust level in the room must therefore be perfectly controlled: the air in the room is renewed 36 times per hour! It is mandatory to wear a full coat, shoe covers and gloves to avoid contaminating the samples.
Each micro-device manufactured in this clean room has 18 channels, or 18 different tests on the same chip. These systems are made of Polydimethylsiloxane (PDMS), a petroleum derivative, and can be produced very quickly: “In one hour, I make you 18 chips,” explains Magalie Faivre.
To create these on-chip laboratories, we use a sort of record player: a platform on which a silicon wafer is placed, then liquid resin is poured onto this wafer which the machine then turns. Depending on the speed of rotation and the viscosity of the liquid deposited, a uniform layer with a well-determined thickness is obtained.
