“…ROS is an important indicator and a major characteristic of several pathological conditions, including cancer, where elevated intracellular levels have been reported in disease conditions . ROS‐responsive drug delivery carriers currently being developed mostly involve organochalcogens (selenium, tellurium, diselenium, and ditellurium), organoboron compounds (aryl boronic ester), sulfur containing compounds (thioether, thioketal, vinyl dithioether), aryl oxalates, and ferrocenes, either as cross‐linkers or as important constituents of polymeric backbone. Although very few studies have been reported for ROS‐responsive nanogels, it would be worthwhile to review some of the important reported results, due to the potential applicability of the ROS‐responsive units in the development of advanced redox‐responsive nanogel‐based systems in the near future.…”