pH/Reduction Dual-Triggered Degradable Poly(doxorubicin) Prodrug Nanoparticles for Leakage-Free Tumor-Specific Self-Delivery.

Poly(doxorubicin) (PDOX) is synthesized with Mn of 1.66 × 104 and DOX content of 78% as prodrug for tumor-specific triggered release, via a facile condensation polymerization of DOX-SS-DOX and adipic dihydrazide. The PDOX nanoparticles (PDOX-NPs) could completely release DOX-SH within 1.5 days at the simulated tumor microenvironment, but no measurable leakage in the physiological media. The in vitro controlled release results show that the releasing rate is influenced by the dosage and independent of the particle size, while the solubility of the degraded products should be the main determining factor for the drug release from the PDOX-NPs. The PDOX-NPs are expected to be promising prodrug nanopharmaceutics for the on-demand self-delivery of DOX with enhanced anticancer efficacy in future tumor treatment.