Nanocomposite Hydrogels: A Promising Approach for Developing Stimuli-responsive Platforms and their Application in Targeted Drug Delivery

With the development of hydrogels from half a century ago, their application in various medical fields, including drug delivery has been widely expanded. Hydrogels used in this field are produced with synthetic polymers such as polyvinylpyrrolidone, polyvinyl alcohol, or natural polymers like chitosan, agarose, and hyaluronic acid to develop biocompatible, biodegradable, and non-immunogenic drug carriers. However, limitations such as inadequate response to stimulation, low homogeneity, and poor loading capacity for hydrophobic drugs have limited the use of hydrogels for drug delivery due to the hydrophilic nature of the hydrogel. The use of nanoparticles in the structure of hydrogels to produce hydrogel nanocomposites leads to more diverse interactions such as hydrogen and electrostatic bonds in addition to covalent interactions between hydrogel polymers. In addition to enhancing the mechanical properties of the hydrogel and further homogeneity, these interactions lead to the formation of platforms responsive to various stimuli, attaining sustained release, and ameliorating the poor loading of hydrophobic drugs used in cancer treatment and wound dressing.

A review of a research conducted in the last 20 years represents that the application of nanocomposite hydrogels in drug delivery includes a wide range of production methods, nanoparticles to create various stimulation mechanisms, and therapeutic applications. Indeed, research has been focused on developing smart systems for controlled release with stimuli to reduce side effects of conventional cancer treatment methods, such as chemotherapy, by targeting drug delivery and reducing drug administration frequency and mitigating chronic wound complications by the release of growth factors.