Enzyme detection

An enzyme detection device for detecting the presence of a protease enzyme in a sample comprising:

• a reaction zone comprising a peptide reactant capable of being cleaved by the enzyme and for receiving a sample;
• a visualisation zone for presenting a signal in response to the detection of the activity of the enzyme;
• and
• a porous membrane interposed between the reaction zone and the visualisation zone, the membrane preventing passage from the reaction zone to the visualisation zone of components having a size greater than a threshold size, wherein cleavage of the peptide reactant in the reaction zone by the enzyme generates a detectable reaction product having a size less than the threshold size and
• wherein the visualisation zone comprises a second reactant which reacts with the reaction product to generate the signal.