本發明揭示一種包含經由二醯肼(dihydrazide)交聯的氧化玻尿酸(oxidated hyaluronic acid)所組成之聚合物的組成物,其中該二醯肼將該氧化玻尿酸交聯。本發明聚合物為一種具有:a)呈透明無色;且b)會在37℃從液態轉變成固態膠體基質等特性的水膠(hydrogel),使其可做為眼球玻璃體替代物。A composition comprising a polymer that comprises oxidated hyaluronic acid cross-linked by a dihydrazide is disclosed. The polymer is a hydrogel exhibiting the following properties: a) transparent and colorless; and b) transforming from a liquid state into a gel-matrix at 37℃. These characteristics make it useful as a vitreous humor substitute.