The 3-D Life PVA-CD Hydrogel FG Kit provides reagents for setting up fast gelling, cell-compatible hydrogels. Its major components are maleimidefunctionalized polyvinyl aclcohol (Mal-PVA) and the crosslinker CD-Link. When the two reagents are combined, thiol groups on CD-Link form stable thioether bonds with maleimide groups on Mal-PVA, which results in the formation of the gel. CD-Link is composed of polyethylene glycol and a matrix metalloprotease (MMP)-cleavable peptide (Pro-Leu-Gly-Leu-Trp-Ala). The MMP-cleavable peptide is designed for a broad range of MMP cleavage including MMPs MMP1, MMP3, MMP7 and MMP9 . It allows cells to spread and migrate within the hydrogel, if they express the indicated MMPs. In most cases cell spreading and migration also requires the presence of adhesion peptides. Prior to the crosslinking step, cell adhesion peptides (e.g. 3-D Life RGD Peptide, Cat.No. 09-P-001) can be covalently attached to a portion of the maleimide groups of Mal-PVA to provide a cell-adhesive matrix.