System and methods for automatic dilution of whole blood to increase plasma clarity

A device for separating plasma from whole blood including turbid plasma comprising:

• a) a reusable hardware component comprising a centrifuge, an interface detector associated with the centrifuge, at least one pump, a first weigh scale, a second weigh scale, and a programmable controller for automatically operating the device;
• b) a single-use fluid flow circuit mounted to the reusable hardware component, wherein the single-use fluid flow circuit comprises a blood source access device, a separation chamber configured to be received in the centrifuge, a first tubing segment connected on a first end to the blood source access device and on a second end to the separation chamber, a container of saline supported by the first weigh scale, a second tubing segment associated with the at least one pump connected on a first end to the container of saline and on a second end to the first tubing segment, a collection container supported by the second weigh scale, and a third tubing segment connected on a first end to the separation chamber and on a second end to the collection container;
• and
• c) wherein the programmable controller is configured to:
• i) prime the single-use fluid flow circuit with saline from the container of saline, ii) flow a volume of the whole blood including turbid plasma through the first tubing segment to the separation chamber prior to adding a volume of additional saline;
• separate the whole blood including turbid plasma in the separation chamber to create a definable interface between the separated plasma and cellular components of the whole blood;
• evaluate the definable interface based on a signal received from the interface detector to determine a volume of saline to be added to the whole blood including turbid plasma flowed through the first tubing segment;
• iii) operate the at least one pump to flow the volume of additional saline from the container of saline through the second tubing segment to the whole blood including turbid plasma that is collected directly from a donor and that is flowing through the first tubing segment, the volume of additional saline being flowed to dilute the whole blood including turbid plasma and to arrive at a predetermined hematocrit to establish the definable interface after separation of the whole blood including turbid plasma in the separation chamber between (a) a layer including the turbid plasma mixed with the volume of additional saline and (b) a cellular component layer, iv) direct flow of the diluted whole blood including turbid plasma to the separation chamber, v) track the volume of additional saline flowed from the container of saline through the second tubing segment to the first tubing segment, wherein said volume of additional saline comprises a tracked volume of saline, vi) flow the separated plasma and the saline from the separation chamber through the third tubing segment to the collection container, and vii) determine a volume for the separated plasma and the saline in the collection container.