Figure 3
Video capture images documenting evaluation of the steps required to set up a density-gradient centrifugation in microgravity conditions. Note that all centrifugation steps were performed terrestrially immediately prior to flight. Analog fluids were used: blood analog was dyed water while Ficoll solution analog was 10% glycerol in PBS. (a) Loading of a LeucoSep 12 ml tube with Ficoll solution analog. (b) Overlay of blood analog. (c) Demonstration that liquids pipetted from ~2 cm away from the barrier (but touching the side wall) are still captured in the appropriate position for the overlay. (d) Evidence that mild manipulations (such as slight tilting of the tube back and forth) did not disturb the integrity of the overlay step. (e) Extraction of the overlaid blood analog. (f) Overlay of a LeucoSep 50 ml tube with blood analog. (g) Image demonstrating that when placed in their proper position, the fluids generally remained in place even for a large-bore 50 ml tube, facilitating operations in microgravity. (h) Extraction step for the 50 ml LeucoSep tube. PBS, phosphate-buffered saline.
