Abstract: Measuring device for determination of the activity or of the concentration of ions in solutions, which has an electrode block having several electrodes and with a flow channel, the flow channel being in connection at its one end with a sample vessel and is connected at its other end to a line, in which a pump is interposed, with calibrating solution containers.Between the pump and the outlet of the electrode block branches off a discharge line, in which a further pump is interposed. Preferably, both pumps are combined into a peristaltic pump, the lines being laid in the segments of the pump.According to a second embodiment, the electrode block is again in connection with the calibrating solution containers. The delivery of the sample is performed however on the same side through a septum. Advantageously, the other side of the electrode block opens out into a pressure equalization vessel, into which a withdrawal line opens in which in turn the above mentioned peristaltic pump is interposed.

Abstract: An apparatus (1) for the drawing off of untreated and treated dialyzing liquid and/or blood from a dialysis device (1) has a dialyzer, from which a first line (22) goes off upstream and a second line (24) goes off downstream, which join into a third line (54). The third line (54) is connected to an analysis device (57). In each of the first and second lines is provided a pump (26, 28) and a shut-off element (56, 56'), between which an overflow (38, 40) per line is arranged. This on the one hand ensures that the liquid in the lines (22, 24) are kept constantly in motion, which prevents the formation of line blockages in the case of liquids tending to coagulate, and on the other hand considerably reduces the displacement time of the liquid to be investigated to the analysis device (57).