Urethral Microenvironment Adapted Sodium Alginate/Gelatin/Reduced Graphene Oxide Biomimetic Patch Improves Scarless Urethral Regeneration (Adv. Sci. 2/2024)

Urethral Reconstruction The nasty urine microenvironment (UME) is an inherent obstacle that hinders urethral repair due to fibrosis and swelling of the hydrogel-based biomaterials. In article number 2302574, Wenyao Li, Qiang Fu, Kaile Zhang, and co-workers report using reduced graphene oxide (rGO) along with double-freezedrying to strengthen a 3D-printed patch for realizing scarless urethral repair. The sodium alginate/gelatin/reduced graphene oxide (SA/Gel/rGO) biomaterial features tunable stiffness, degradation profile, and anti-fibrosis performance. Interestingly, the 3D-printed alginate-containing composite scaffold is able to respond to Ca2+ present in the urine, leading to enhanced structural stability and strength as well as inhibiting swelling. The proposed strategy has the potential of resolving the dilemma of necessary biomaterial stiffness and unwanted fibrosis in urethral repair.