Bisphosphonate-containing supramolecular hydrogels for topical decorporation of uranium-contaminated wounds in mice

Purpose: Personnel experiencing accidents that involve radionuclides or victims of potential malicious radioactive attacks may suffer injuries with wounds contaminated by radionuclides. The current treatment for contamination from uranium in external injuries is the use of saline solution to wash the wounds, which has the drawback of further spreading of the contaminants due to the flow of water. To minimize the cost of storage of contaminated liquids and to improve the efficiency of treatment, we propose the use of hydrogels as a form of decorporation agent. Methods: Mice with uranium-contaminated wounds on their backs were treated with bisphosphonate or diethylene triamine pentaacetic acid (DTPA) containing supramolecular hydrogels. Survival rates of the treated mice and changes in the body weight of the mice were observed and compared to those of mice without hydrogel treatment. Distribution of uranium in the mice was also explored as proof of the effectiveness of the hydrogel treatment. Results: The survival rate of the hydrogel-treated mice was significantly higher than that of the mice without treatment. The body weights of the hydrogel-treated mice showed significant recovery after 10 days while the body weight of mice without hydrogel treatment continuously decreased. The amount of uranyl ions in the organs (mainly concentrated in the kidney) of the hydrogel-treated mice was much smaller than that of the mice without hydrogel treatment. Conclusions: By incorporating uranium chelating agents, we developed new supramolecular hydrogels that could effectively and conveniently decorporate uranium ions from the contaminated wound sites of mice, with the highest efficacy achieved by our pamidronate-based molecular hydrogel.