Silk-Based Proteins as Natural Mucoadhesive Polymers for Controlled Drug Delivery

Mucoadhesive polymers, either synthetic or natural, are most commonly used for the development of different kinds of drug delivery systems (DDS). They have several potential features which can be used for the drug targeting and controlled drug delivery such as chitosan, alginate, and cellulose derivatives. Presently, silk-based mucoadhesive polymers and their derivative have gained attention due to their directed release, protection properties, and less toxic nature. Natural silk is a protein-based fibre produced from several arthropods like silkworms, bees, spiders, ants, and lacewing insects, which produce sticky silk-like glue substances. These polymers have various chemical groups that play a major role in the formulation of controlled and targeted DDS. Hence, they may be a good choice for the development of controlled drug delivery. The silk-based polymers can be tailored to be more effective and applicable by using recombinant technologies. Due to its low immunogenicity and versatility in being manufactured into a variety of material types, such as particles, sponges, hydrogels, and films, silk protein has gained attention in this regard. Silk-protein-based polymers have shown various promising approaches in cancer treatment, protein delivery, gene therapy, and many others. Therefore, this chapter covers the various sources of silk protein polymers and their features for potential applications in the targeted drug delivery.