PEGSSDA enables quickly and gently dissolve HyStem gels non-enzymatically, allowing easy recovery of cells or spheroids either grown on top or within the hydrogel. Contains two internal disulfide bonds which can be rapidly reduced with small amounts of reducing agent (such as N-acetyl cysteine or glutathione), causing gel liquefaction. PEG gels are widely recognized as a biocompatible, non-immunogenic, and capable of chemical manipulation to incorporate attachment peptides degradable peptides and other moieties.