Methods and systems for high-throughput blood component collection

A method for collecting a blood component, the method comprising:

• drawing whole blood into a centrifuge;
• spinning the centrifuge to cause centrifugal force to act on the whole blood to separate the whole blood into a least a first blood component and a second blood component that is different from the first blood component;
• extracting the first blood component from the centrifuge;
• detecting when the second blood component is about to be extracted from the centrifuge;
• after the second blood component is detected and while the centrifuge continues to spin, flowing the separated first blood component back towards the centrifuge to move at least the second blood component from the centrifuge;
• monitoring an inlet pressure of the whole blood entering the centrifuge;
• determining a back pressure at the inlet of the centrifuge;
• and
• equating a change in back pressure with a radial position of an interface between the first blood component and the second blood component in the centrifuge.