Apparatus for treating whole blood comprising concentric cylinders defining an annulus therebetween

Apparatus for collecting platelets from blood comprising:

• concentric outer and inner cylinders defining an annulus therebetween, the inner cylinder adapted for rotation with respect to the outer cylinder;
• at least one of an inner surface of the outer cylinder or an outer surface of the inner cylinder including two parallel porous membranes defining a first compartment therebetween and a second compartment between the membranes and the surface, the membrane closest to the surface having a pore size adapted to restrict the passage of platelets and the membrane farthest from the surface having a pore size adapted to allow the passage of platelets but to restrict the passage of other blood components;
• an inlet for introducing blood into the annulus for flow along the cylinders;
• means for removing platelets from the first compartment;
• and
• an outlet port for discharging the blood.

An apparatus for continuous treatment of a mixture comprising liquid and solid components, comprising:

• concentric outer and inner cylinders defining an annulus therebetween, the inner cylinder adapted for rotation with respect to the outer cylinder;
• at least one of an inner surface of the outer cylinder or an outer surface of the inner cylinder including a porous membrane covered portion forming a compartment containing a reactant for treatment of the liquid component of the mixture;
• an inlet for introducing the mixture into the annulus for flow along the cylinders;
• and
• an outlet port for discharging the mixture,
• wherein the porous membrane allows the liquid portion of the mixture to interact with the reactant while restricting the solid portion of the mixture from interacting with the reactant.