Influence of fluid absorption time on cell recovery in cytocentrifugation.
OBJECTIVE
To determine the absorption time required to give complete cell recovery in cytocentrifugation.


METHODS
A simplified model for cell recovery was outlined that relates cell recovery to the relative magnitude of cell sedimentation velocity (SV) and fluid velocity (FV) during cytocentrifugation. The recovery of blood leukocytes was measured at various relative values of the SV/FV ratio and plotted to provide an indication of the effect of the ratio on recovery and to identify the conditions necessary to yield complete cell recovery.


RESULTS
As SV/FV approaches zero, cell recovery also approaches zero. As the SV/FV ratio increases, recovery increases toward a maximum of 100%. The fluid absorption time is a key factor in the SV/FV ratio, which also includes centrifugal force and sample volume. A preliminary evaluation of commercial equipment yielded a wide range of absorption characteristics. In addition, fluid flow can be slowed and the SV/FV ratio increased by adding macromolecules--e.g., bovine serum albumin--to the sample fluid.


CONCLUSIONS
Cytocentrifugation has the capability of nearly complete cell recovery if conditions are selected that yield a high SV/FV ratio. Such recovery usually requires slowing the fluid flow rate beyond what is normally obtained in most commercial equipment.
Biological Research and Development Department, Wescor, Inc., Logan, Utah 84321, USA.
B O
BO
Stokes
E
E
Blee
M L
ML
Grover
D001799:Blood Sedimentation / Q000187:drug effects; D002498:Centrifugation / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D007962:Leukocytes / Q000166:cytology; D012710:Serum Albumin, Bovine / Q000494:pharmacology
D012710:Serum Albumin, Bovine