Micro-Free Flow Electrophoresis chip for analyzing or separating a sample including a pile comprising: - at least a first plate and a second plate, - characterized in that the chip further comprises - a sheet uniformly disposed between the first and second plates, a part of said sheet being hollowed out for designing a fluidic circuit, wherein the fluidic circuit is partially or totally graved or cut or holed out of the sheet, said fluidic circuit comprising at least three inlets, at least one outlet, and a separation zone comprising at least one separation chamber having walls defined by the height of the sheet and being confined by the plates, - clamping means, - in-between the sheet and the second plate, n stacks composed of a plate and a sheet, n being zero or a positive integer, each sheet comprising at least three inlets: - one inlet arranged for entry of a first fluid electrode, - one inlet arranged for entry of a second fluid electrode and - one inlet arranged for entry of a sample, and at least one outlet for exit of: - a first fluid electrode intended to flow, in each separation chamber, along a first side of the separation chamber, - a second fluid electrode intended to flow, in each separation chamber, along a second side of the separation chamber opposite to the first side, - a sample intended to flow, in each separation chamber, between the first and second fluid electrodes, said first and second fluid electrodes in each separation chamber being configured to be in contact with means for generating an electric field to apply an electric field to the separation chamber. - at least a first plate and a second plate, - characterized in that the chip further comprises - a sheet uniformly disposed between the first and second plates, a part of said sheet being hollowed out for designing a fluidic circuit, wherein the fluidic circuit is partially or totally graved or cut or holed out of the sheet, said fluidic circuit comprising at least three inlets, at least one outlet, and a separation zone comprising at least one separation chamber having walls defined by the height of the sheet and being confined by the plates, - clamping means, - in-between the sheet and the second plate, n stacks composed of a plate and a sheet, n being zero or a positive integer, each sheet comprising at least three inlets: - one inlet arranged for entry of a first fluid electrode, - one inlet arranged for entry of a second fluid electrode and - one inlet arranged for entry of a sample, and at least one outlet for exit of: each sheet comprising at least three inlets: - one inlet arranged for entry of a first fluid electrode, - one inlet arranged for entry of a second fluid electrode and - one inlet arranged for entry of a sample, - one inlet arranged for entry of a first fluid electrode, - one inlet arranged for entry of a second fluid electrode and - one inlet arranged for entry of a sample, and at least one outlet for exit of: - a first fluid electrode intended to flow, in each separation chamber, along a first side of the separation chamber, - a second fluid electrode intended to flow, in each separation chamber, along a second side of the separation chamber opposite to the first side, - a sample intended to flow, in each separation chamber, between the first and second fluid electrodes,