Biological responses of novel high-toughness double network hydrogels in muscle and the subcutaneous tissues.

The study evaluated biological reaction of four types of novel double network gels in muscle and subcutaneous tissues, using implantation tests according to the international guideline. The implantation tests demonstrated that, although poly (2-acrylamide-2-metyl-propane sulfonic acid)/poly (N,N'-dimetyl acrylamide) (PAMPS/PDMAAm) gel induced a mild inflammation at 1 week, the degree of the inflammation significantly decreased into the same degree as that of the negative control at 4 and 6 weeks. This gel has a potential to be applied as artificial cartilage. In addition, Cellulose/Gelatin gel showed the same degree of inflammation as that of the negative control at 1 week, and then, showed a gradually absorbable property at 4 and 6 weeks. This gel has a potential to be applied as an absorbable implant. The PAMPS/polyacrylamide and Cellulose/PDMAAm gels induced a significant inflammation at each week. These DN gels are difficult to be applied as clinical implants in the current situation.