Abstract: A fluid sampling system for biotechnological applications, comprises a bioreactor chamber (2) for a fluid culture medium (4) containing cells (6) and further comprising transfer means (8) for transferring controlled amounts of culture medium from said bioreactor chamber to a target container (10). The transfer means comprise: a perfusion probe (12) with a fluid-tight probe housing surrounding an internal probe volume (14) and having an inlet probe aperture (16) and an outlet probe aperture (18); a fluid filtering element (20) sealingly connected to the probe housing and forming a cover of the inlet probe aperture. A fluid connection line comprises a fluid receptacle (30) disposed between the outlet probe aperture (18) of the perfusion probe and the target container (10) and disposed on a weight measuring station (32) configured for acquisition of a weight signal corresponding to the fluid receptacle's momentary weight.