Te 2000s eclipse

The DUC tissues were frozen at −80 °C overnight and were lyophilized in a freeze-drier (TrioScience, Istanbol, Turkey) for 24 h. The lyophilized DUC samples were then cryo milled to powder, and gel was prepared as previously described [34 (link)]. Briefly, the dried DUC powder from 4–5 donors was pooled and digested with 1 mg pepsin/mL (Sigma, USA; then, it was dissolved in 0.05 M HCl) per 10 mg DUC tissue under constant agitation for 48 h at room temperature. Ten and twenty milligram powdered tissue was exposed to UV light for 30 min inside the biosafety cabinet for disinfection, followed by the addition of 1 mL of pepsin/HCL (to make 10 mg/mL and 20 mg/mL hydrogel) in each of the vials for up to 48 h at room temperature with constant agitation to ensure complete digestion and formation of a pre-gel liquid which was then neutralized by the addition of ice-cold solution of 1 M NaOH (1/10th of original digest volume) and 10X PBS (1/10 of final neutralized volume) to attain a pH of 7.4. Neutralized pre-gel solution was allowed to gel by incubation at 37 °C (NU5500E, NuAire, USA) for 20–30 min to be completely turned into hydrogel. Gelation was confirmed either macroscopically or microscopically under phase contrast microscope (TE 2000S Eclipse, Nikon, Tokyo, Japan).