The line of fluorogenic peptide substrates is a line of high-quality substrates that allow the testing of protease serines. They target enzymes involved in coagulation and fibrinolysis such as thrombin, Factor Xa, Factor XIIa, kallikrein, activated C protein, plasmin and plasminogen-SK.
Fluorogenic substrates are synthetic peptides that react with proteolytic enzymes by releasing a colour that can be followed by spectrophotometry and whose intensity is proportional to the proteolytic activity of the enzyme.
Typically, such substrates are composed of 3 to 5 natural or artificial amino acids. Their structures can be protected in N-terminal to reduce undesirable degradation by aminopeptidases. Their C-terminal ends are modified so that, when the amide bond is cleaved, a fluorogen group is released. The most commonly used group is 7-amino-4-methylcoumarin (AMC) with 342 nm wavelength excitation and 440 nm wavelength emission.