The invention relates to a microfluidic device comprising at least one micro-channel connected at one end to an enclosed area, characterized in that it also comprises an inlet circuit and an outlet circuit connected to the enclosed area and between which the fluid can be discharged without any contact with the micro-channel, wherein at least one of said inlet and outlet circuits can be controlled in such a way that the pressure at the end of the micro-channel can be modified independently from the pressure at the other end of the micro-channel.