Abstract: A device for generating micro- and nanoflow mobile phase gradients for high performance liquid chromatography includes a generator of micro- and nanoflows of at least two mobile phases in different percentage compositions; an n-position gradient distributor having inlet and outlet ports and n couples of ports for a like number of capillary loops, each selectively connectable at one end with the inlet port and at its other end to the outlet port, which in turn is connectable to an analytical circuit that includes a chromatographic column and a detector; a micro- and nanoflow meter connected to the analytical circuit; a flow deviator having an inlet connected to the outlet of the gradient distributor, one outlet connected to a discharge and another outlet connected to the micro- and nanoflow meter, and a control unit that includes means of control of the generator of micro- and nanoflows such to create the different mobile phase mixture compositions, means for controlling the gradient distributor, means for con

Abstract: A flow regulator device for an analytical circuit, characterised by comprising: a fluid restriction (R) of defined characteristics related to the field of application of the analytical circuit, a direct-pressure regulator (2) positioned upstream of said restriction (R), a back pressure regulator (4) positioned downstream of said restriction (R).