A Review on: Smart Hydrogel Materials for Local Delivery Drugs

Hydrogels are highly hydrated mesh networks formed from natural, synthetic, or semi-synthetic polymers, which are physically or covalently crosslinked. This class of material is used for local drug delivery because they provide high biocompatibility, drug protection, control of the drug release, and physicochemical modifications. Furthermore, hydrogels enable the encapsulation and the delivery of drugs covering wide range of properties, including small molecules, proteins and nucleic acids. Hydrogels are attractive materials for the controlled release of therapeutics because of their capacity to embed biologically active agents in their water-swollen network. Hydrogels are a unique type of material since they consist of an autonomous, water-swollen three-dimensional viscoelastic network that enables molecules and cells to attach and diffuse. Nevertheless, hydrogels recently received substantial attention because they were used in various biomedical applications such as wound healing, cell therapies, cartilage and bone regeneration, and controlled release of drugs. Their biocompatibility and morphological similarity to natural tissue are the reasons behind this. Hydrogels and hydrogel drug delivery systems are traditionally defined as being natural or synthetic. Hydrogels still interest material scientists and medical researchers nowadays, and many advances have been made in their formulations and applications. The primary objective of this article is to explore the classification of hydrogels based on various criteria, their properties, methods of preparation, and their characteristics.