Abstract: Apparatus (100) for the quantification of biological components (3, 3?, 3?) in a fluid comprising: a measurement cell (1) comprising detection electrodes (4, 4?, 5, 5?, 6, 6?, 34, 34?, 84, 84?, 94, 94?, 184, 184?, 194, 194?) and reference electrodes (7, 7,? 8, 8?, 9, 9?, 37, 37?, 64, 64?, 74, 74?, 164, 164?, 174?); an electronic unit (201) for the generation of input signals, impedimetric measurement, amplification of output signals and communication with a user interface; means for the generation of a magnetic field (101, 102, 103) with an appropriate gradient that can be modulated in time, said means of magnetisation being configured to generate a magnetic field capable of causing, in combination with concentrators (10, 10?, 10?, 14, 14?, 14?, 15) housed in the measurement cell, the separation of the components (3, 3?, 3?) to be quantified from the rest of the solution and their concentration on the detection electrodes (4, 4?, 5, 5?, 6, 6?, 34, 34?, 84, 84?, 94, 94?, 184, 184?, 194, 194?).