A microsystem for separating fluids not miscible with each other and contained in a mixture. The microsystem comprises at least one detection means intended to inspect at least one area of the mixture and to detect the presence of at least one of the fluids in this area. The microsystem further comprises at least one controlled means for opening or closing a passage. The microsystem further comprises at least one control means for the opening or the closing of a passage as a function of the nature of the fluid detected in the area inspected by the detection means, in such a way that the fluid whose presence has been detected flows or not through the passage. The detection means comprise a plurality of sensors arranged substantially around the controlled means.