Ultrasmall WS₂ Quantum Dots with Visible Fluorescence for Protection of Cells and Animal Models from Radiation-Induced Damages

Two-dimensional WS 2 materials have attracted wide attention in condensed physics and materials science due to its unique geometric and electronic structures. Particularly, WS 2 shows extraordinary catalytic activities when its size decreases to ultrasmall, which provides potential opportunities for medical applications. In this work, WS 2 quantum dots with strong catalytic properties were used for in vitro and in vivo protection from ionizing radiation induced cell damages. WS 2 quantum dots possess unique optical properties of blue photoluminescence emission and excitation-wavelength dependent emission profiles. In vitro studies showed that cell viability can be considerably improved and cellular reactive oxygen species (ROS) can be removed by WS 2 quantum dots. In vivo studies showed WS 2 quantum dots can effectively protect the hematopoietic system and DNA from damages caused by high-energy radiation through removing whole-body excessive ROS. Furthermore, WS 2 quantum dots showed nearly 80% renal clearance within 24 h post injection and did not cause any obvious toxicities in up to 30 days after treatment.