Abstract: A device for determining the concentration of at least one substance in organic tissue includes a subcutaneous needle for insertion into the tissue and a pumping and suction unit which is controlled by a microprocessor and is used for delivering a perfusion fluid and draining it after its partial equilibration with the tissue. The device further includes a sensing unit connected to the microprocessor for determining the concentration of the substance to be analyzed and one or more marker variables. The perfusion fluid, a calibrating solution and at least one drug are provided in replaceable metering ampoules sealed with membranes, whose metering plungers can be actuated by a drive unit controlled by the microprocessor. The metering ampoules communicate with a master capillary leading from the pumping and suction unit to the subcutaneous needle; communication is established via capillary tubes piercing the membranes.

Abstract: In order to determine at least one parameter of interest in a living organism, a perfusion is directly introduced in the tissues. After its partial balancing by the tissue parameter of interest, the perfusion fluid is collected and analyzed for the parameter of interest, as well as for endogenous or exogenous marker properties indicative of the degree of interaction between the perfusion fluid and the tissue, in such a way that the parameters of interest can be determined with the help of such characteristic properties. Contrary to usual processes, used exclusively inside blood vessels or other body cavities filled with liquid, this process creates in the tissues, i.e. in the closed cellular structure, a previously inexistent cavity, in which the perfusion fluid introduced in the tissue interacts directly with the organic tissue, with no intervening membranes.

Abstract: For optical determination of the catalytic enzyme activity of a sample by means of enzyme reactants which are split under the influence of the enzyme to be measured, the enzyme reactant is placed at the end of an optical fiber and brought into contact with the sample to be determined. The measurements are carried out by observing the rate of change in spectral characteristics of the enzyme reactant, or its reaction products, resulting from the enzyme reaction. The method permits measurements of undiluted blood and in-vivo determinations of enzyme activities.

Abstract: A method for the quantitative determination of one or more chemical parameters of a sample medium employs a fluorescent agent which is not responsive to the parameter to be determined and which has an excitation spectrum and an emission spectrum, and a closely adjacent chromogenic agent which responds to the parameter of the sample medium to be determined by a change in its absorption spectrum the emission spectrum of the fluorescent agent at least partically overlapping the absorption spectrum of the chromogenic agent. The absorption maximum of chromogenic agent is shifted in accordance with the parameter to be determined, causing a reduction of fluorescence decay time t in the fluorescent agent, thereby enabling quantitative determination of the chemical parameter with improved long-term stability and infrequent calibrations.

Abstract: Method for analysing gaseous or liquid samples, utilising a one-way measuring element with a measuring channel containing at least one optical or electrochemical sensor and being provided with sealing elements on either end. In order to obtain accurate measurements in a simple manner the proposal is put forward that for measuring purposes a storage medium in the measuring channel be replaced by a separating medium which should then be replaced by the sample. Sample and storage medium will remain in the measuring element when it is discarded.

Abstract: A device designed for determining one or more medical variables in living organisms, comprises a part to be inserted into the tissue of the organism, which has an exchange channel with openings into the tissue. The device comprising a delivery unit connected with the exchange channel for the delivery of a perfusion fluid and its drainage after partial equilibration with the medical variable or quantity to be measured, i.e., preferably glucose concentration, and comparatively constant endogenous or exogenous marker variables. The device further comprising an analyzing unit for measuring the medical variable and one marker variable, and an evaluation unit for determining the actual concentration of the medical variable with the use of the marker variables.

Abstract: In order to calibrate a measurement apparatus used for determining at least the pH and pCO.sub.2 values in aqueous media, two aqueous base solutions A and B with good storage stability are mixed at a defined ratio immediately prior to calibration, the desired pH and pCO.sub.2 values being provided for calibration of the measuring electrodes of the measurement apparatus only after chemical reaction of the base solutions A and B has taken place.

Abstract: In order to simplify the performance of serial measurements by means of a measuring device for determining chemical parameters of an aqueous sample, with at least one symmetrical, ion-sensitive membrane being located between the sample and an electrolytic medium and the sample and the electrolytic medium being in contact with reference electrodes connected to an evaluation unit, a measuring element is provided which can be inserted into a measuring device and which has a sample chamber connected with a reference chamber via a bore. At least one measuring chamber is provided, which is separated from the sample chamber by a symmetrical, ion-sensitive membrane. The reference chamber and all measuring chambers contain electrolytic media into which are dipped the reference electrodes located in the measuring device.

Abstract: An analyzing apparatus for the purpose of analyzing samples of body fluids, comprising a sample feeding device and a measuring channel in which measuring probes are contained. In order to attain good reproducibility and uniform conditions of treatment of the samples the measuring channel is separated by means of a valve from a storage tank communicating with the sample feeding device.

Abstract: Due to the size of the devices used for the excitation and measuring of light, conventional sensor elements for optically determining the concentrations of substances contained in gaseous and liquid samples, featuring an indicator layer with one or more indicator substances, are not well suited for use with microanalysis equipment, nor are they easy to mass-produce. These disadvantages are eliminated by integrating on the carrier layer (1) at least one photosensitive element (3) and its electric contact leads in planar arrangement, and by establishing optical contact between the indicator substance (7, 7') of the indicator layer (6) stimulated by the excitation radiation (11), and the photosensitive elements (3).

Abstract: In order to produce a small-volume flow measuring cell with good flow characteristics in a sensor device for determining the concentration of a substrate in a sample medium, comprising an enzyme electrode which is covered by a membrane and a reference electrode, both of which are in contact with the measuring cell, the proposal is put forward that the reference electrode be located outside of the membrane cover of the enzyme electrode and that the maximum extension of the flow measuring cell normal to the flow direction of the sample medium essentially be the same as the diameter of the sensitive layer of the enzyme electrode.

Abstract: In order to reduce the measuring volume in a device for measuring chemical and physical parameters of liquid or gaseous media by means of optical sensor elements whose optodes may be replaced easily, a measuring unit with a sample channel is provided which may be inserted into a supporting frame of the device and which may be connected to ingoing and outgoing sample lines via capillary bores. The measuring unit contains a sensor carrier forming the boundary of the sample channel on one side, which sensor carrier has bores holding the optodes. The indicator film of each individual optode is situated in the plane of the sensor carrier facing the sample channel.

Abstract: Electromagnetically actuated valve, comprising an actuating device, a movable plunger and a valve chamber with an opening for the medium passing through it, which opening may be closed by the plunger. In order to ensure safe functioning of the valve at small closing forces, the valve chamber is totally sealed against the actuating device and the movable plunger by means of a flexible diaphragm, the diaphragm being fitted into the housing along its circumference and being pressed against the edge of the opening by the movable plunger.