Transfer Freezing Bag Sets for Cord Blood Processing and Freezing Cellbios provides transfer freezing bags for red blood cell depletion and Volume reduction to acquire concentrated cord blood stem cells to treat various diseases. Closed cord blood collection methods have proven to be superior to open in reducing the risk of microbial contamination. Efficient banking requires volume reduction of cord blood units without significant loss of progenitor cells, to decrease storage space and cost, and this may be achieved by using the separation techniques. Advantages Closed System Processing Maximum Stem Cell Recovery Negligible RBCâ??s Contamination Applicable to Top and Bottom Method Gamma Sterilization