Humedics Gmbh

Charité – Universitätsmedizin Berlin

Freie Universitat Berlin

Freie Universitaet Berlin

Charité Universitaetmedizin Berlin

Charite - Universitaetsmedizin Berlin

Martin Stockmann

Karsten Heyne

Tom Rubin

Björn Riecke

Bjön Riecke

Bjoern Riecke

A method for determining the metabolic capacity of an enzyme includes time-resolved determination of the concentration of a product in exhaled air. The product is created by metabolism of a substrate, previously administered to an individual, by an enzyme of the individual. The product concentration is determined until the maximum product concentration in the exhaled air is reached. A model function is fitted to measured values of the product concentration, obtained by the time-resolved determination of the product concentration between start and end times. The metabolic capacity of the enzyme is determined based on parameters of the model function. Determining the metabolic capacity of the enzyme takes place based on at least two parameters of the model function, wherein the maximum value and time constant of the model function are not selected as parameters at the same time, and the start and/or end times are not selected as parameters.

Method for determining the metabolic capacity of at least one enzyme

An analysis method determines a functional parameter of an organ by measuringCOcontent in exhaled air of an individual to which a substrate has been administered. The reaction of the substrate in the body of the individual enriches the exhaled air withCO. The maximum reaction rate of the substrate in the body is determined via a change of the measuredCOcontent in the exhaled air using zero-order enzyme kinetics. An aqueous methacetin solution having a pH greater than 7.0 is used in the analysis method. A face mask separates the exhaled air from inhaled air. The face mask is configured such that inhaled and exhaled air flows essentially completely through the face mask. Exhalation and inhalation valves in the face mask allow a flow of inhaled and exhaled air through the face mask. A diagnostic method is used to determine the functional parameters of the organ.

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The invention relates to an analysis method for determining a functional parameter of an organ of a human or animal individual by measuring theCOcontent in the air exhaled by the individual to which a substrate has been administered the reaction of which in the body of the individual enriches the air exhaled by the individual withCO. The method is characterized by using a measuring device, the maximum reaction rate of the substrate in the body of the individual being determined via a change of the measuredCOcontent in the air exhaled by the individual using zero-order enzyme kinetics. The invention also relates to an aqueous methacetin solution for use in said analysis method, the pH of the solution being greater 7.0. The invention also relates to a face mask () for use in the inventive method for separating the exhaled air from the air inhaled by an individual. Said face mask comprises a face mask body () and an air cushion () encircling the face mask body. Said air cushion is filled with a gas and establishes a substantially gas-tight contact between the face of the individual and the face mask () placed on the face of the individual so that the air required by the individual for breathing and the air exhaled by the individual has to flow essentially completely through the face mask (). At least one exhalation valve () and at least one inhalation valve () are integrated into the face mask and allow a flow of inhaled and exhaled air through the face mask. The invention finally relates to a diagnostic method for determining the functional parameters of an organ of a human or animal individual.

Method of breath analysis for determining liver capacity or microcirculation using 13C-labeled methacetin substrate

Face mask

Growing community of inventors

Berlin, Germany

Martin Stockmann