Rapid prototyping of tubular polyurethane and cell/hydrogel constructs

A tubular polyurethane (PU) sandwich-like, adipose-derived stem cell (ADSC)/gelatin/alginate/fibrin construct was fabricated using a double-nozzle, low-temperature (-20 degrees C) deposition technique. The ADSCs survived the fabrication and cryopreservation stages by incorporating a cryoprotectant (glycerol or dimethyl sulfoxide (DMSO)) in the cell/hydrogel system. With 5% DMSO or 10% glycerol alone in the hydrogel, the cell viabilities were retained (73% and 62%, respectively). The three-dimensional construct was effectively preserved below -80 degrees C for more than 1 week. After the freeze/thaw processes, cell viability and proliferation ability were regained. This strategy has the potential to be widely used in complex organ manufacturing techniques.