The PL Chip for T-TAS® 01 incorporates an array of 26 collagen coated microfluidic capillary channels in parallel.  BAPA anticoagulated whole blood loaded to the PL Chip Reservoir is flowed through the channels at arterial shear rates to produce platelet activation and aggregation.  The combination of collagen adhesion and arterial shear stress allows the T-TAS 01 with PL Chip to more closely mimic in vivo primary hemostasis.
As whole blood travels through the collagen coated capillaries at arterial shear stresses, platelets adhere to the collagen surface in a von Willebrand Factor (vWF)dependent matter.  Once attached, platelets activate and release agonists, such as ADP and Thromboxane A2 that recruit and activate additional platelets to the site of attachment leading to the formation and growth of the platelet thrombus.
The microcapillaries gradually become occluded as the platelet thrombus grows.  The T-TAS 01 instrument measures the increase in flow pressure that is caused by the occlusion.  When there is a defect in primary hemostasis—such as when a patient is taking antiplatelet therapy, has von Willebrand disease, or has an inherited or acquired defect in primary hemostatic ability—occlusion of the capillaries is reduced.

Each box contains 20 individual microfluidic chips, each with 2 channels for easy replicate production

Each microfluidic channel contains 26 collagen coated micro-capillaries in parallel to normalize data.

Platelets adhere and aggregate on the surface of the collagen-coated capillary channels of the PL chip as the blood moved through the analytical path of the TTAS.  The aggregate gradually increases in size as the activated platelets bind additional platelets in the area occluding the path, resulting in an increase in flow pressure that is measured by the TTAS.  That changes in the flow pressure pattern reflect the formation processes of the platelet plug.

The PL Chip has only a single output parameter that is used to quantify primary hemostasis.  The Area Under the pressure-time Curve (AUC).  The 10 minute AUC represents the total thrombogenicity and integrates onset time, as well as the growth and stability of the formed thrombi.

TTAS AUC Normal

TTAS AUC Abnormal

The PL Chip is stable for ~18 months from manufacture and until the day listed on the label when stored at 4oC.  Once removed from the sealed pouch, the PL Chip should be used within 8 hours.