Subsequently, a reaction between the new epoxide and another alcoholate anion occurred, leading to the completion of the cross-link.Reaction conditions and the chemical composition of the chitin/CMC hydrogels are listed in Table 1. The hydrogel samples of GEL55, GEL46, GEL37,and GEL28 having different ratios of chitin to CMC were prepared successfully with ECH as a cross-linker.