Degradation-induced swelling in implanted hydrogels can cause severe adverse reactions in surrounding tissues. Here, we report a new class of hydrogel with extremely low swelling pressure, and demonstrate its use as an artificial vitreous body. The hydrogel has ultralow polymer content (4.0 g l−1), low cytotoxicity, and forms in situ in 10 minutes via the crosslinking of clusters of highly branched polymers of tetra-armed poly(ethylene glycol) prepolymers. After injection and gelation in the eyes of rabbits, the hydrogel functioned as an artificial vitreous body for over a year without adverse effects, and proved effective for the treatment of retinal detachment. The properties of the hydrogel make it a promising candidate as an infill biomaterial for a range of biomedical applications.
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This work was supported by the Japan Society for the Promotion of Science (JSPS) through Grants-in-Aid for the Graduate Program for Leaders in Life Innovation (GPLLI), by the International Core Research Center for Nanobio, Core-to-Core Program A. Advanced Research Networks, and Grants-in-Aid for Young Scientists (A) grant number 23700555 to T.S., Scientific Research (S) grant number 16H06312 to U.C., and Scientific Research (C) grant number 26462631 to F.O. This work was also supported by the Japan Science and Technology Agency (JST) through the S-innovation program and Center of Innovation program (to U.C.) and PREST (to T.S.).
The authors declare no competing financial interests.
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Hayashi, K., Okamoto, F., Hoshi, S. et al. Fast-forming hydrogel with ultralow polymeric content as an artificial vitreous body. Nat Biomed Eng 1, 0044 (2017). https://doi.org/10.1038/s41551-017-0044
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