The new MP-Reagent (microparticle reagent) contains the same amount of phospholipids as in all our PPP-Reagents, that is, a final concentration of 4 M phospholipids. This reagent can best be used in combination with CTI (Corn Trypsin Inhibitor) because the system will become extremely sensitive to both TF as well as contact activation. CTI is able to inhibit factor XIIa and thereby inhibits this potential contact activation. The CTI can best be added to the citrate on which the blood is collected (ref Dargaud et al, J Thromb Haemost 2006; 4: 1160–1).