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arXiv · 1603.09212

Highly Catalytic Nanodots with Renal Clearance for Radiation Protection

Abstract

Ionizing radiation (gamma and x-ray) is widely used in industry and medicine, but it can also pose a significant hazardous effect on health and induce cancer, physical deformity and even death, due to DNA damages and invasion of free radicals. There is therefore an urgent unmet demand in designing highly efficient radioprotectants with synergetic integration of effective renal clearance and low toxicity. In this study, we designed ultrasmall (sub-5 nm) highly catalytically active and cysteine-protected MoS2 dots as radioprotectants and investigated their application in protection against ionizing radiation. In vivo preclinical studies showed that the surviving fraction of MoS2-treated mice can appreciably increase to up to 79 % when they were exposed to high-energy ionizing radiation. Furthermore, MoS2 dots can contribute in cleaning up the accumulated free radicals within the body, repairing DNA damages and recovering all vital chemical and biochemical indicators, suggesting their unique role as free radical scavengers. MoS2 dots showed rapid and efficient urinary excretion with more than 80 % injected dose (I.D.) eliminated from the body after 24 hours due to their ultrasmall hydrodynamic size and did not cause any noticeable toxic responses up to 30 days.

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Xiao-Dong Zhang, Jinxuan Zhang, Junying Wang, Jiang Yang, Jie Chen, Xiu Shen, Jiao Deng, Dehui Deng, Wei Long, Yuan-Ming Sun, Changlong Liu, Meixian Li. 2016-03-30. Highly Catalytic Nanodots with Renal Clearance for Radiation Protection. https://doi.org/10.1021/acsnano.6b00321

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