Bioorthogonal catalysis offers a unique strategy to modulate biological processes through the in situ generation of therapeutic agents. However, the direct application of bioorthogonal transition metal catalysts (TMCs) in complex media poses numerous challenges due to issues of limited biocompatibility, poor water solubility, and catalyst deactivation in biological environments. We report here the creation of catalytic "polyzymes", comprised of self-assembled polymer nanoparticles engineered to encapsulate lipophilic TMCs. The incorporation of catalysts into these nanoparticle scaffolds creates water-soluble constructs that provide a protective environment for the catalyst. The potential therapeutic utility of these nanozymes was demonstrated through antimicrobial studies in which a cationic nanozyme was able to penetrate into biofilms and eradicate embedded bacteria through the bioorthogonal activation of a proantibiotic.

In this work, a series of branched polycaprolactone (BPCL) samples with different ε-caprolactone (CL) chain lengths were synthesized and used to toughen poly (lactic acid) (PLA). The spherical structure increased the free volume, facilitating the free movement of the PLA chain segment and increasing the ductility. In addition, the hydrogen bonds between the multiterminal hydroxyl group of BPCL x and PLA improved the interaction between them. The glass-transition temperatures (T g ) and crystallization temperatures (T c ) of the blends were significantly lower than those of PLA, and these temperatures increased with the chain length of polycaprolactone. BPCL x increased the crystallization rate of PLA through heterogeneous nucleation. A longer chain length of CL increased the mutual entanglement in the blends, reduced the hydrogen bonding between BPCL x and PLA, and increased the entanglement of BPCL x chains. When the chain length of CL was 6, the impact strength and elongation at break of the PLA/BPCL blends exhibited an increase of 151.72 and 465.8%, respectively, as compared with PLA.