Trace-Water-Induced Competitive Coordination Synthesis and Functionalization of Porphyrinic Metal-Organic Framework Nanoparticles for Treatment of Hypoxic Tumors.

Controlling the size and morphology of metal-organic frameworks (MOF) has received increasing research interest but remains a great challenge. In this work, we demonstrate a trace-water-induced competitive coordination procedure to controllably synthesize porphyrinic MOFs including needle-shaped nanomaterials, hollow nanotubes, and nanocubes, using 5,10,15,20-tetrakis(4-carboxyphenyl) porphyrin as organic linkers and Zr 4+ as inorganic building blocks. These three MOFs exhibited shape-dependent singlet oxygen ( 1 O 2 ) production under 655 nm laser irradiation. The designed nanocubes were functionalized by coating a MnO 2 shell, which can effectively generate 1 O 2 in the tumor microenvironment (TME) to improve photodynamic therapy (PDT). Moreover, they reacted with GSH, and the resulted Mn 2+ ions generated hydroxyl radicals (·OH) for chemodynamic therapy (CDT). Therefore, the designed MOFs@MnO 2 nanoparticles were responsive to the hypoxic TME to improve the efficiency of PDT and incorporate CDT for tumor ablation.