Nanohydrogels are the hydrogels that are prepared in water by self-aggregation of polymers of natural origin like dextran. These types of hydrogels are formed from natural polysaccharides like dextran, pullulan, or cholesterol-containing polysaccharides.Polymeric micelles have several advantages over other nanosized drug delivery systems, such as a smaller size as compared to, for instance, liposomes, which is important for, e.g., percutaneous lymphatic delivery or extravasation from blood vessels into the tumor tissue. Polymeric micelles are based on block-copolymers with hydrophilic and hydrophobic units that self-assemble in an aqueous environment into structures composed of a hydrophobic core stabilized by a hydrophilic shell.