Spectrophotometric method to quantify and discriminate urokinase and tissue-type plasminogen activators

✍ Scribed by Jörg Schnyder; Roland Marti; Philip H. Cooper; Trevor G. Payne

• Book ID: 102988809
• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 746 KB
• Volume: 200
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(92)90292-f

✦ Synopsis

Plasminogen activator and urokinase are often used as biological markers of cell activation. However, the methods currently used are cumbersome, make no discrimination between tissue-type plasminogen activator and urokinase, and do not allow expression of the results of the overall reaction in International Units. The one-step method described in this paper lacks these drawbacks. Moreover, we propose use of H-D-Val-Phe-Lys-4-nitroanilide as substrate which has a lower Km than the standard H-D-Val-Leu-Lys-4-nitroanilide which is commercially available. Low concentrations of sodium dodecyl sulfate in the reaction mixture dramatically and preferentially accelerate the reaction catalyzed by tissue-type plasminogen activators. Identical results are obtained under kinetic or fixed-time assay conditions using either a photometer or 96-well plate reader. The corresponding formulae are provided.