Technoclone Factor IX Deficient Plasma is an immunodepleted lyophilized, stabilized human plasma with a coagulation activity < 1% of factor IX, prepared from HIV 1/2 Ab negative plasmas. All other coagulation factors are in the normal range. Factor IX deficient plasma immunads. is used in the determination of Coagulation Factor IX by one-stage method based on the Activated Partial Thromboplastin Time (aPTT).