The gel is formed by stable thioether bonds between thiol groups on CD cell-degradable crosslinker and thio-reactive groups on SLO-PVA. The polymer, SLO-PVA is functionalized with thiol-reactive groups which react with crosslinker at slower rate than maleimides in FAST-PVA. SLO-PVA does not have sites for cell attachment, but it can be customized to conjugate RGD peptide using TrueGel3D RGD peptide (TRUERGD-1EA) prior to the crosslinking step. The CD cell-degradable crosslinker is composed of matrix metalloprotease (MMP)-cleavable peptide (Pro-Leu-Gly-Leu-Trp-Ala), which allows cells to spread and migrate by secreting matrix metalloproteases (MMP1, MMP3, MMP7 and MMP9).
Application: TRUE8-1KT is used to generate hydrogels of different stiffness (0.15 to 5 KPa shear modulus) to mimic in-vivo conditions and to investigate the effect of matrix stiffness on cell physiology and behavior. These hydrogels are also employed to study cell migration of neutrophils, dendritic cells and lymphocytes. The SLO-PVA based hydrogels are preferred over dextran-based gels for long-term culture of cells producing carbohydrate degrading enzymes.