An in vitro method for specifically removing or isolating plasminogen or plasmin in presence of fibrinogen from a mixture containing plasminogen or plasmin by contacting the mixture in with a rigid amino acid wherein the amino group of the amino acid and the carboxylic group of the amino acid are 0.6 to 0.8 nm, preferably 0.7 nm apart and the rigid amino acid is covalently bound to a support via the amino group of the amino acid. Tranexamic acid and 4-aminomethylbicyclo[2.2.2]octane-1- carboxylic acid are the preferred rigid amino acid. Disclosed is also a support having covalently bound a rigid amino acid wherein the amino group of the amino acid and the carboxylic group of the amino acid are apart 0.6 to 0.8 nm, preferably 0.7 nm.An in vitro method for specifically removing or isolating plasminogen or plasmin in presence of fibrinogen from a mixture containing plasminogen or plasmin by contacting the mixture in with a rigid amino acid wherein the amino group of the amino acid and the carboxylic group of the amino acid are 0.6 to 0.8 nm, preferably 0.7 nm apart and the rigid amino acid is covalently bound to a support via the amino group of the amino acid. Tranexamic acid and 4-aminomethylbicyclo[2.2.2]octane-1- carboxylic acid are the preferred rigid amino acid. Disclosed is also a support having covalently bound a rigid amino acid wherein the amino group of the amino acid and the carboxylic group of the amino acid are apart 0.6 to 0.8 nm, preferably 0.7 nm.
