A nanogel is a polymer-based, crosslinked hydrogel particle on the sub-micron scale.[1][2][3] These complex networks of polymers present a unique opportunity in the field of drug delivery at the intersection of nanoparticles and hydrogel synthesis.[1][2][3] Nanogels can be natural, synthetic, or a combination of the two and have a high degree of tunability in terms of their size, shape, surface functionalization, and degradation mechanisms.[1][2][3] Given these inherent characteristics in addition to their biocompatibility and capacity to encapsulate small drugs and molecules, nanogels are a promising strategy to treat disease and dysfunction by serving as delivery vehicles capable of navigating across challenging physiological barriers within the body.[1][2][3]
Nanogels are not to be confused with Nanogel aerogel, a lightweight thermal insulator, or with nanocomposite hydrogels (NC gels), which are nanomaterial-filled, hydrated, polymeric networks that exhibit higher elasticity and strength relative to traditionally made hydrogels.