A Tungsten Nitride‐Based O₂ Self‐Sufficient Nanoplatform for Enhanced Photodynamic Therapy against Hypoxic Tumors

Abstract

The hypoxic microenvironment of tumors is a natural barrier to photodynamic therapy (PDT) and closely related to the tumor metastasis. Here, chlorine e6 (Ce6) decorated tungsten nitride nanoparticles (WN NPs) with a folic acid (FA) modification are fabricated to produce FA-WN-Ce6 (FWC) NPs for enhanced photodynamic therapy against hypoxic tumors. FWC NPs can efficiently accumulate in tumor sites via FA-mediated specific tumor targeting. With 630 nm laser irradiation, the WN in FWC can act as a photocatalyst for water splitting to provide oxygen (O 2 ), which significantly improves the reactive oxygen species (ROS) generation ability of Ce6 in hypoxia and achieves an enhanced PDT effect both in vitro and in vivo. In addition, the O 2 produced by FWC NPs can also weaken the hypoxia level in tumor tissue, and thus reduces the invasion and metastasis of tumor cells. Additionally, no apparent systemic toxicity is observed after the treatment of FWC NPs.Overall, these results indicate the great potential of FWC NPs as safe and effective nanoplatform for both enhanced tumor PDT and against metastasis.

Photodynamic Therapy of Inorganic Complexes for the Treatment of Cancer†

“…In contrast, the cell viabilities for FWC NPs were less than 30% in both normoxia and hypoxia at the same Ce6 concentration (4 µg mL −1 ). To conclude, FWC NPs could have an excellent PDT effect in hypoxic tumor tissues (135).…”

Recent Advances in Strategies for Addressing Hypoxia in Tumor Photodynamic Therapy

“…C 5 N 2 nanoparticles [ 109 ], C 3 N 4 [ 110 , 111 ], tungsten nitride [ 112 ], carbon nanodot [ 113 ], graphdiyne oxide [ 114 ], iron disulfide (FeS 2 ) [ 115 ], cobalt phytate [ 116 ], etc., have been used in the water-splitting strategy. C 3 N 4 -related materials have been intensively studied for the enhancement of PDT via water splitting-mediated oxygen generation.…”

Nanomedicine-Based Strategies Assisting Photodynamic Therapy for Hypoxic Tumors: State-of-the-Art Approaches and Emerging Trends

“…Zheng et al decorated a C 3 N 4 nanocomposite with carbon dots that enhanced red light absorption and showed that the decorated nanocomposite efficiently produced oxygen from water [ 56 ]. Wang et al also introduced the tungsten nitride (WN)-based nanomaterial that was originally designed for green energy application via water splitting to provide oxygen support to oxygen-enhanced PDT against hypoxic tumors [ 57 , 58 ]. Unlike semiconductor photocatalysts, WN with metallic properties could photocatalyze overall water splitting at longer wavelengths, up to 765 nm, which is suitable for in vivo oxygen production via water splitting due to the better light penetration.…”