No abstract

Black phosphorus (BP) nanomaterials have emerged as rapidly rising stars in the field of nanomedicine. In this work, BP quantum dots (BPQDs) are synthesized and their potential as photosensitizers is investigated for the first time. The BPQDs present good stability in physiological medium and no appreciable cytotoxicity. More importantly, the BPQDs can be rapidly eliminated from the body in their intact form via renal clearance due to their ultrasmall hydrodynamic diameter (5.4 nm). Both in vitro and in vivo studies indicate that the BPQDs have excellent photodynamic effect under light irradiation that can effectively generate reactive oxygen species to kill cancer cells. The BPQDs thus can serve as biocompatible and powerful photosensitizers for efficient photodynamic therapy.

Hydrogen (H2) therapy is a highly promising strategy against several diseases due to its inherent biosafety. However, the current H2 treatment modalities rely predominantly on the systemic administration of the gas, resulting in poor targeting and utilization. Furthermore, although H2 has significant anti-tumor effects, the underlying mechanisms have not yet been elucidated. Due to their ultrasmall size, nanomaterials are highly suitable drug-delivery systems with a myriad of biomedical applications. Nanocarrier-mediated H2 delivery, as well as in situ production of H2 by nanogenerators, can significantly improve targeted accumulation of the gas and accelerate the therapeutic effects. In addition, nanomaterials can be further modified to enhance passive or active accumulation at the target site. In this Perspective, we summarize the mechanism of H2 therapy and describe possibilities for combining H2 therapy with nanomaterials. We also discuss the current challenges of H2 therapy and provide some insights into this burgeoning field.

Excessive production of oxidative species alters the normal redox balance and leads to diseases,s uch as chronic inflammation and cancer.O xidative species are short-lived species,w hich makes direct, precise,a nd real-time measurements difficult. Herein, we report an ovel core-satellite gold nanostructure for dual, ratiometric surface-enhanced Raman scattering (SERS) and photoacoustic (PA) imaging to enable the precise detection of inflammation/cancer-related H 2 O 2 .The combination of H 2 O 2-activated second near-infrared (NIR-II) PA imaging and SERS imaging enables the differentiation between the inflamed region and normal tissue with high accuracy.The mesoporous silica shell of the nanoprobe could be used to deliver drugs to the target area to precisely treat disease.T herefore,t his core-satellite nanostructure can not only quantitatively and precisely monitor H 2 O 2 produced in inflammation, tumor,and osteoarthritis in rabbits in real-time, but can also be used to track the progress of the antiinflammatory treatment in real-time.