Recent advances in polymers, preparation techniques, applications and future perspectives of hydrogels

Abstract

Drug delivery via hydrogel is one of the most effective methods. Hydrogels have been described as polymeric water-swollen materials and retain water in distinctive three-dimensional complex. These are classified as pH sensitive hydrogels, temperature sensitive hydrogels, homo-polymer hydrogels, co-polymer hydrogels and Interpenetrating Network (IP-N) hydrogel. Hydrogels can be prepared via various techniques, including physical crosslinking, chemical crosslinking, free radical polymerization, photo-initiator's and hydrogen bonding. Various polymers in manufacturing includes pectin, chitosan, cyclodextrin and carrageenan, etc. This review aims to describes hydrogels for drug delivery, classifications, preparation techniques, various polymers in hydrogel preparation and highlights novel applications of hydrogels in medicine.