MICRO FLOW FILTRATION SYSTEM AND FLOW FILTRATION METHOD FOR A FLUID SAMPLE

A flow filtration system (1) for concentration of components contained in a fluid sample comprises a fluid channel (2) being formed by two conduits (4, 5) allowing a bidirectional flow of the fluid sample through the fluid channel (2), a tangential flow filtration module (3) and at least two pairs (8, 9) of piston pumps (6) each having two piston pumps (6), wherein the piston pumps (6) having a piston swept volume forming a reservoir being able to contain the fluid for volumes of up to 100 ml. The tangential flow filtration module (3) is located in the fluid channel (2) so that a fluid flowing through the channel (2) passes through the filtration module (3). At each end (10, 11) of the channel (2) one piston pump (6) of each pair (8, 9) of piston pumps (6) is located in such a manner that the piston pumps are fluidically connected in parallel. The system (1) is arranged and adapted such that during the concentration process at least for a predetermined period of time only one of the pairs (8, 9) of piston pumps (6) is used to drive the fluid through the tangential flow filtration module (3).