Patent ID: 7090996

Claim:
A process for examining at least one parameter of membrane enclosed biocompartments, wherein the biocompartments are arranged in an examination chamber which is continually or intermittently exposed to a culture medium, and wherein the biocompartments release or consume a substance by metabolic action, the process comprising: a) applying an electrical voltage to the culture medium between an operating electrode placed in an area of the examination chamber and a reference electrode separated from the operating electrode, so that hydroxyl ions or hydrogen ions are formed from the substance in the medium; b) measuring a first measurement value for a pH value of the culture medium at a measuring location in said area of the examination chamber; c) before or after measurement of the first measurement value, taking at least one second measurement value for the pH value of the culture medium at said measuring location in said area of said examination chamber; and d) calculating a difference between the first measurement value and the second measurement value to produce a measurement value difference; e) determining the at least one parameter of the biocompartments using the measurement value difference.