Determining protease in biological sample, comprises converting proform of protease into active protease, contacting test sample with substrate, at which inhibitor binding substance is bound and separating substrate with protease inhibitor

Determining a protease preferably when protease is present in a form after its proform and in a form that is inhibited by a protease inhibitor, in a biological sample, comprises: converting the proform of the protease into an active protease; contacting the test sample with a substrate, at which an inhibitor binding substance is bound; and separating the substrate bound with protease inhibitor from the test sample, where a substrate for the protease whose activity to be determined is added to the test sample and the proteolytic conversion of the substrate is determined by the protease. Determining a protease preferably when protease is present in a form after its proform and in a form that is inhibited by a protease inhibitor, in a biological sample, comprises: converting the proform of the protease into an active protease; contacting the test sample with a substrate, at which an inhibitor binding substance is bound covalently or by adsorption, where the inhibitor binding substance has higher affinity (binding strength) to the protease inhibitor than the protease; and separating the substrate bound with protease inhibitor from the test sample, where a substrate for the protease whose activity to be determined is added to the test sample and the proteolytic conversion of the substrate is determined by the protease. An independent claim is included for a device for performing the above method, where the substrate is agarose gel or cellulose. Verfahren zur Bestimmung einer Protease in einer biologischen Probe, insbesondere wenn neben der Proform der Protease auch die Protease selbst, und wenigstens ein zu der Protease korrespondierender Proteaseinhibitor vorliegt, mit den Stufen: a) Umwandlung der Proform der Protease in die aktive Protease, b) der so gebildeten Protease in der Messprobe wird der Proteaseinhibitor entzogen, indem man die Messprobe mit einem Trägermaterial in Kontakt bringt, an welchem eine Inhibitorbindesubstanz kovalent oder adsorptiv gebunden ist, die eine höhere Affinität (Bindungsstärke) zu dem Proteaseinhibitor besitzt als die Protease selbst, c) das Trägermaterial mit daran gebundenem Proteaseinhibitor wird von der Messprobe separiert, wobei der Messprobe ein Substrat für die wenigstens eine Protease, deren Aktivität zu bestimmen ist, zugegeben und die proteolytische Umsetzung des Substrats durch die Protease erfasst wird.