Nanogels as Drug Delivery Carrier: A Narrative Review on Formulation Techniques, Characterization, Applications and Patents

Under the umbrella of targeted drug delivery systems, several techniques are unleashed in the market that allow a drug or other pharmacologically active material to be delivered to the target cell to treat a condition or health problem. The improvement of the pharmaceutical delivery systems' effectiveness, safety, and stability is accomplished through the Formulation of the nano-gel-based delivery system. Nanogels are aqueous dispersions of submicron-sized, three-dimensional, strongly cross-linked networks of hydrophilic polymers that are inflated by water. Through a variety of delivery routes, such as oral, pulmonary, nasal, parenteral, and intraocular, an active pharmaceutical agent or therapeutic agent with a high or low molecular weight can be easily encapsulated into nanogels. Nanogels have been researched as drug delivery systems due to their beneficial qualities, such as biocompatibility, high stability, flexible particle size, drug loading capacity, and potential surface modification for active targeting by attaching ligands that recognize cognate receptors on target cells or tissues. By responding to internal or external stimuli, including pH, temperature, light, and redox, nano gels can be made to be stimulus-responsive, allowing for regulated drug release. Thus, in the fact of said characteristics’ of nano gels, this review manuscript aims to provide an overview of characterization, evaluation, formulation technique, recent applications, and patents of nano gels.