A thermo-responsive hydrogel, including a biocompatible monomer and/or polymer having a side chain-linked amino acid. The hydrogel is thermo-responsive at a physiological temperature, and can include, incorporate, or encapsulate a treatment agent, such as a drug composition, a biomolecule, and/or a nanoparticle. The hydrogel is useful in delivering the treatment agent. The hydrogel is in a first physicochemical state for administration to a mammal. The hydrogel is thermo-responsive at a physiological temperature of the mammal, and changes to a second physicochemical state that is more solid than the first physicochemical state. In the second physicochemical state the thermo-responsive hydrogel releases the treatment agent.
