A hydrogel is a three-dimensional (3D) network of hydrophilic polymers that can swell in water and hold a large amount of water while maintaining the structure due to chemical or physical cross-linking of individual polymer chains. Hydrogels were first reported by Wichterle and Lím (1960) [1].

When was hydrogel invented?

Since then, the term “hydrogel” was used to describe a 3-dimensional network of hydrophilic natural polymers and gums, in which the network is formed chemically or physically. The hydrogel of current understanding for biological use was first developed by Wichterle and Lim in 1960 [1].

Who created hydrogel?

With the establishment of the first synthetic hydrogels by Wichterle and Lim in 1954 [13], the hydrogel technologies may be applied to hygienic products [14], agriculture [15], drug delivery systems [14], [16], sealing [14], coal dewatering [17], artificial snow [14], food additives [18], pharmaceuticals [19], ...