A digital holographic microscopy image of red blood cellsWIKIMEDA, EGELBERGThe technique: Dialysis with decreasing saline concentrations gently cleanses thawed red blood cells of the toxic cryoprotectant glycerol. This microfluidic approach cuts the time for glycerol removal from an hour down to three minutes, bioengineers Ratih Lusianti and Adam Higgins of Oregon State University reported last month (October 28) in Biomicrofluidics.
The process shields the cells from osmotic shock and lowers the glycerol concentration from 40 percent to 0.4 percent. More than 90 percent of the cells remain intact.
“I think exposing [red blood cells to glycerol] stepwise and smoothly as they did here is a very great approach,” said Utkan Demirci, a bioengineer at Stanford University School of Medicine who was not involved in the study. “This may pave the way for some automated systems in the future.”
The significance: Glycerol, a simple sugar alcohol, protects cryopreserved cells from damage by disrupting the formation of ice crystals. But glycerol must be washed from blood cells before they can be used for transfusions. The existing washing protocol involves a slow series of centrifugations, which limits the ...
