Centrifugal field flow fractionation device

A centrifugal field-flow fractionation device comprising:

• a rotor configured to rotate about a rotation axis;
• a flow path member formed in an arc-shape centering the rotation axis, the flow path member being attached to the rotor, the flow path member being provided with a flow path therein, an inlet port for introducing a liquid sample to the flow path, and an outlet port for discharging the liquid sample from the flow path;
• a sample introduction part configured to introduce the liquid sample from the inlet port into the flow path and flow the liquid sample in the flow path to the outlet port;
• a rotation drive unit configured to rotate the rotor to classify particles in the liquid sample in the flow path by centrifugal force;
• and
• a controller configured to control introduction of the liquid sample by the sample introduction part and rotation drive of the rotor by the rotation drive unit,
• wherein the controller is configured to rotate the rotor at a first rotational speed when introducing the liquid sample into the flow path and rotate the rotor at a second rotational speed slower than the first rotational speed, and
• wherein the controller decreases a rotational speed of the rotor from the first rotational speed to the second rotational speed during a period of time which occurs between stopping a flow of the liquid sample into the flow path and resuming the flow of the liquid sample into the flow path.

A centrifugal field-flow fractionation device comprising:

• a rotor configured to rotate about a rotation axis;
• a flow path member formed in an arc-shape centering the rotation axis, the flow path member being attached to the rotor, the flow path member being provided with a flow path therein, an inlet port for introducing a liquid sample to the flow path, and an outlet port for discharging the liquid sample from the flow path;
• a sample introduction part configured to introduce the liquid sample from the inlet port into the flow path and flow the liquid sample in the flow path to the outlet port;
• a rotation drive unit configured to rotate the rotor to classify particles in the liquid sample in the flow path by centrifugal force;
• and
• a controller configured to control introduction of the liquid sample by the sample introduction part and rotation drive of the rotor by the rotation drive unit,
• wherein the controller is configured to rotate the rotor at a first rotational speed when introducing the liquid sample into the flow path and rotate the rotor at a second rotational speed slower than the first rotational speed, and
• wherein the controller starts an operation of decreasing a rotational speed from the first rotational speed to the second rotational speed while the liquid sample is being introduced into the flow path and stops the flow of the liquid sample into the flow path before a rotation speed of the rotor reaches the second rotational speed.