An improved method for measuring red blood cell filterability

A new simple method for measuring red blood cell (RBC) filterability by weighing the amount of RBC filtered through micropore membranes is described. Red cell filterability by weighing (RCFW) is determined on washed RBC resuspended in phosphate-buffered saline (PBS) at low (5%) hematocrit. The filtration step is performed using gravity alone and the amount of the filtered suspension is referred to the filtration of PBS alone through the same membrane. The new method shows a reproducibility better than that of the widely used Dormandy technique, with a lower coefficient of variation (5.3 vs. 7.2%) and a higher sensitivity to artificially hardened RBC.