Injectable self-assembled bola-dipeptide hydrogels for sustained photodynamic prodrug delivery and enhanced tumor therapy

Supramolecular peptide materials have attracted increasing attention due to their natural biological origin and versatile applications. However, it is often challenging to control and modulate the self-assembly of peptides (especially short peptides) for constructing hydrogels with tunable mechanical properties and adaptive injectability toward biomedical applications. Here, we report a supramolecular strategy for forming robust and injectable hydrogels based on the self-assembly of a rationally designed bola-dipeptide. The self-assembled hydrogels exhibit versatile functionalities, including flow under shear stress, good recovery properties, and easy encapsulation of hydrophilic prodrugs. The prodrug-loaded hydrogels show sustained release profiles, inhibited nontargeted leakage, and enhanced localized prodrug conversion, leading to highly efficient photodynamic tumor ablation. Hence, the supramolecular strategy is promising for the rational construction of injectable hydrogels toward targeted and sustained prodrug conversion and tumor therapy.