Automatic Coagulation Profile System
Stanford L. Adler, Ann Tse, R. M. Widmark · Journal of Applied Physics · 1971
A fully automatic system is described which simultaneously performs prothrombin time and activated partial thromboplastin time for coagulation defect screening and anticoagulant therapy control, using a new end point detection technique that provides greater sensitivity and a sharp, clearly defined end point. A sample of plasma is metered onto a section of film bearing a predeposited spot of magnetic iron oxide that is resuspended in the plasma. This mixture is opaque to the electro-optical system until the end point occurs, then abruptly becomes transparent.