Cell separation method and apparatus
Disclosed herein are apparatus and methods for isolating a fraction of interest from a physiological fluid sample. A sample holder for isolating a fraction of interest from a physiological fluid sample includes a flexible compartment and a rigid exoskeleton that supports the flexible compartment. The flexible compartment may have at least one reservoir with a height to volume ratio of about 0.1 cm/mL to about 5 cm/mL. An automated device for extracting a fraction of interest from the sample includes a sample holder with a flexible compartment supported by a rigid exoskeleton, a support for the sample holder connected to one or more fluid extraction devices, and a motor for moving the extraction device relative to the sample holder. The automated device may include an optical sensor and may include a clamp for clamping the flexible compartment.
1. A physiological fluid sample holder for isolating a fraction of interest comprising:
a flexible compartment shaped to define an elongated flexible reservoir with a height to volume ratio of about 0.1 cm/mL to about 5 cm/mL, and an upper reservoir above and in fluid communication with the elongated flexible reservoir, the elongated flexible reservoir being narrower in at least one cross dimension and having a large height to volume ratio relative to the upper reservoir; and
a rigid exoskeleton that supports the flexible compartment, the exoskeleton comprising a top portion and a bottom portion, the top and bottom portions being separable as the flexible compartment is supported by the upper portion to expose the elongated flexible reservoir.
2. The physiological fluid sample holder of claim 1 , wherein the elongated flexible reservoir has a height to volume ratio between about 3 to 4 times the height to volume ratio of the upper reservoir.
3. The physiological fluid sample holder of claim 1 , wherein the height to volume ratio of the elongated flexible reservoir is about 2 to 10 times the height to volume ratio of the upper reservoir.
4. The physiological fluid sample holder of claim 1 , wherein the height to volume ratio of the elongated flexible reservoir is about 3.4 times the height to volume ratio of the upper reservoir.
5. The physiological fluid sample holder of claim 1 , wherein the exoskeleton is configured to be inserted into a centrifuge.
6. The physiological fluid sample holder of claim 1 , wherein the volumes of the elongated flexible reservoir and the upper reservoir are selected to isolate the fraction of interest in the elongated flexible reservoir.
7. The physiological fluid sample holder of claim 1 , further comprising
a fluid extraction device comprising a cannula to draw fluid from the flexible compartment through the cannula; and
wherein the top portion of the exoskeleton comprises a cap mated to the flexible compartment, the cap having a vent to allow air to enter the flexible compartment as the fluid is drawn from the flexible compartment.
8. The physiological sample holder of claim 1 , wherein the upper reservoir tapers down to the elongated flexible reservoir.
9. The physiological sample holder of claim 1 , wherein the elongated flexible reservoir is flat, depth of the elongated flexible reservoir being substantially less than width and height of the elongated flexible reservoir.