Hydrogel Polymers consist of porous, permeable solids and at least 10% by weight or volume of interstitial fluid that is entirely or primarily made of water. It is a biphasic material. The porous permeable solid in hydrogels is a three-dimensional network of natural or synthetic polymers and a fluid that has absorbed a lot of water or biological fluids but is not water-soluble. Many applications, notably in the biological field, are supported by these characteristics. Although some hydrogels come from nature, most are made synthetically.