Ristocetin Cofactor Assay

The Ristocetin Cofactor Assay is used for the quantitative determination of Factor VIII Ristocetin Cofactor activity in plasma.

Von Willebrand disease is associated with a decrease in Von Willebrand factor or Ristocetin Cofactor activity and it is generally accepted that the Ristocetin Cofactor activity is the most useful in vitro assay for the diagnosis of Von Willebrand disease. Levels of Ristocetin Cofactor activity are determined by the ability of the test plasma and Ristocetin to induce aggregation in a standardised platelet suspension.

Lyophilised platelets are a preparation of fixed human platelets which have been lyophilised for long-term stability. Each vial of lyophilised platelets is reconstituted with the appropriate volume of Tris Buffered Saline to yield a platelet count of approximately 275,000 per μL.

Provided as a kit and as separate components.

Platelet Agonists

Both quantitative and qualitative platelet defects can result in altered Haemostasis. We provide the common agonists ADP to assess normal platelet function and aid in the diagnosis of platelet function defects by way of Platelet Aggregometry.

Ristocetin is a lyophilised reagent derived from Norcardia lurida which induces platelet aggregation in normal Platelet Rich Plasma (PRP). In Von Willebrands disease, Ristocetin-induced platelet aggregation is impaired.

Platelet Aggregation Reagents

PART NUMBER PRODUCT NAME PACKAGING STABILITY

50750 Ristocetin Cofactor Assay Ristocetin: 7.5 mg/vial Lyophilised Human Platelets: 6 mL Von Willebrand Reference Plasma: Normal 1 mL Von Willebrand Reference Plasma: Deficient 0.5 mL Tris Buffered Saline (TBS): 12 mL

Ristocetin: 7 days at 2-8°C Lyophilised Human Platelets: 8 days at 2-8°C Von Willebrand Reference Plasma: Normal 4 hours at 2-8°C Von Willebrand Reference Plasma: Deficient 4 hours at 2-8°C Tris Buffered Saline (TBS): until expiration date

50705 Ristocetin 7.5 mg/vial 10 x 0.5 mL 7 days at 2-8°C

50710 Platelets 3 x 6 mL 8 days at 2-8°C

PART NUMBER PRODUCT NAME PACKAGING STABILITY

50704 ADP 3 x 0.5 mL 30 days at 2-8°C

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