Oxygen-evolving hollow polydopamine alleviates tumour hypoxia for enhancing photodynamic therapy in cancer treatment.

Hypoxia, a characteristic hallmark of solid tumours, restricts the therapeutic effect of photodynamic therapy (PDT) for cancer treatment. To address this issue, a facile and nanosized oxygen (O) bubble template is established by mixing oxygenated water and water-soluble solvents for guiding hollow polydopamine (HPDA) synthesis, and O is encapsulated in the cavity of HPDA. HPDA with abundant catechol is designed as a carrier for zinc phthalocyanine (ZnPc, a boronic acid modified photosensitizer) borate ester bonds to fabricate nanomedicine (denoted as HZNPs).