Hydrogel based drug delivery system: A review

Hydrogels are the three-dimensional hydrophilic network which is crosslinked physically or chemically. also called as gels because they absorb considerate amount of water. The characteristic properties hydrogels swelling, mechanical properties, biodegradable, elasticity, biocompatible, easy to modify, flexibility, etc. They classified based on source, polymeric composition, biodegradability, configuration, cross linking, physical appearance, chemical charges, and drug release. can be synthesized from natural, synthetic, semisynthetic polymers via physical, crosslinking, through grafting, coacervation polymerization. useful in daily life their major applications delivery oral cavity, GI tract, rectal, ocular, protein, subcutaneous, transdermal, controlled delivery, preparation contact lenses, wound healing, tissue engineering, biosensing, bacterial culture preparation, various other fields like agriculture, electronics, cosmetics, gene perfume regenerative medicine, plastic surgery, sealant adhesive, watering beads for plant water purification.