Incorporation of DMSO and dextran-40 into a gelatin/alginate hydrogel for controlled assembled cell cryopreservation.

A new cell cryopreservation strategy for cell-assembling constructs was proposed. With this strategy, different concentrations of dimethysulfoxide (DMSO) and dextran-40 were directly incorporated into the cell/gelatin/alginate systems, prototyped according to a predesigned structure, cryopreserved at -80 °C for 10 days and followed a thawing process at 17 °C. The rheological properties, bonding water contents and melting points of the gelatin/alginate hydrogel systems were changed with the addition of different amounts of DMSO. The microscopy analysis, (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrasodium bromide (MTT) and hematoxylin and eosin (HE) staining indicated that the cell numbers were progressively in a selected DMSO concentration range. With DMSO 5% (v/v) alone, the metabolic rate in the construct attained (81.3±5.7)%. A synergistic effect was achieved with the combination of the DMSO/gelatin/alginate and dextran-40/gelatin/alginate hydrogel systems. These results indicated that the inclusion of DMSO and dextran-40 in the hydrogel could effectively enhance the cell preservation effects. This cryopreservation strategy holds the ability to be widely used in organ manufacturing techniques.