Figure 1
Mechanical and physical characterization of TG-PEG hydrogels. (A) Scheme of modular designed TG-PEG hydrogels. By combining different PEG backbone molecules and cell-adhesion peptide RGD, hydrogels with different degradability, cell adhesion properties and stiffness can be engineered and cross-linked in the presence of cells under physiological conditions. (B–D) Rheological characterization of TG-PEG hydrogels. (B) Representative mechanical profile consisting of storage modulus (G′, represented as dots) and loss modulus (G′′, represented as crosses) of TG-PEG hydrogels at different polymer concentrations ranging from 1.1% to 3.4% (w/v). Storage moduli of hydrogels after reaching a plateau at 30 min (C) at different polymer concentrations (n = 3) or (D) at a fixed 1.7% (w/v) polymer concentration containing MMPsensitive (Deg) or MMPnon-degradable (Non Deg) cross-links, and with and without RGD adhesion sites (n = 3). (E) MMP1-mediated degradation over time of different percentages of TG-PEG hydrogels containing MMPsensitive (Deg) or MMPnon-degradable (Non Deg) cross-links. Degradation of cross-links results in the swelling of hydrogels (n = 5). All data are reported as mean ± standard error. ANOVA with Tukey’s post hoc test *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.
