A multistage-dialysis microdevice for extraction of cryoprotectants.

In this study, we present a multistage-dialysis microdevice (MDM) for extraction of cryoprotectants (CPAs) from a CPA-laden cell suspension. We confirmed the functions of the key designs of the MDM using a fluorescence solution, we assessed the performance of the MDM by using the MDM to unload glycerin from glycerin-loaded swine erythrocytes, and we investigated the effects of the cell suspension flow rate, glycerin concentration, cell density, and membrane pore size on the clearance efficiency of glycerin (CG), the survival rate of cells (SC), and the recovery rate of cells (RC). Under the designed conditions, CG, SC, and RC reached ~60%, ~90%, and ~70%, respectively. In addition, a high flow rate causes high SC and RC but a low CG. For a low glycerin concentration, CG, SC, and RC are all high. If a low cell density or a large pore membrane is used, CG is high, whereas both SC and RC are low. This work provides insight into the development of microfluidic devices for the inline extraction of cryoprotectants from a small volume of cryopreserved cells prior to the use of the cells in lab-on-a-chip applications.