The invention concerns a device and a method for the manipulation of a liquid sample material in which magnetic microparticles are suspended whereby the microparticles have a functionalized surface and an analyte is bound to the surface. The sample material is introduced into a device with a liquid system through an injection device (50) and in a first mobile phase the sample material is carried to an extractor (90). In a section (97) of the extractor (90) the microparticles are immobilized by means of a magnetic field of a controllable means (96) and separated from the remaining sample material. By switching over of a switching unit (110) a second mobile phase (75) is carried to the extractor (90) and the second mobile phase (75) detaches the adsorbed analyte from the surface of the microparticles. The second mobile phase (75) with the dissolved analyte(s) can be analyzed by way of chromatographic separation (130) and subsequent detection (140).