Fig. 3: EV hydrogels with tunable gelation temperature, storage moduli, and stress relaxation half-lives.
From: Injectable extracellular vesicle hydrogels with tunable viscoelasticity for depot vaccine
EV gels were formed by mixing 8-arm DBCO-PEG and different concentrations of azido-labeled EVs. An EV concentration of 7 × 109/mL, 1.75 × 109/mL, 1.17 × 109/mL, 0.875 × 109/mL, and 0.70 × 109/mL was used for EV gel-1, EV gel-2, EV gel-3, EV gel-4, and EV gel-5, respectively. Shown are the changes of storage moduli (G’) and loss moduli (G”) of a EV gel-1, b EV-gel 2, and c EV-gel 3 at constant strain (γ = 0.5%) during heating from 20 °C to 80 °C, measured at a heating speed of 5 °C/min. Changes of G’ and G” over step time at 37 °C for d EV gel-1, e EV gel-2, and f EV gel-3. g Representative stress relaxation curves and h stress relaxation half-lives of EV gel 1–5. i Porosity of EV gels (n = 4 technical replicates, ANOVA with a post hoc Fisher’s LSD test was used. 0.01 <*P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001; ****P ≤ 0.0001).
