| abstract |
(57) [Problem] To provide a thermoreversible hydrogel-forming composition capable of favorably maintaining the original activity of a physiologically active substance held in a gel. A composition comprising at least a hydrogel-forming polymer, water, and a physiologically active substance. The sol-gel transition temperature (first sol-gel transition temperature) is 5 ° C. or more and 40 ° C. And a water-insoluble hydrogel state substantially at a temperature higher than the sol-gel transition temperature, and reversibly water-soluble at a temperature lower than the sol-gel transition temperature. |