Drug Implants of Hydrogels via Collective Behavior of Microgel Colloids for On-Demand Cancer Therapy.

In nature, the collective behaviors such as the growth of bacteria and the cooperation of insects possess great superiority and can create functional materials through diversified interactions for accomplishing complex tasks that cannot be performed by a single unit. Here we develop a new protocol for fabricating drug implants of hydrogels via the collective behavior of jagged magnetic microgels constructed by further coating Au nanorod@SiO 2 with the thermo- and magnetic-responsive polymer shells, poly( N -isopropylacrylamide- co -magnetic ionic liquids). The magnetism of resultant macroscale hydrogels was enhanced nearly 5-fold because of the self-organization process, presenting new evidence for the essence of magnetism generation at a molecular level. By virtue of using a near-IR laser excitation stimulus, minimal cytotoxicity, and high biocompatibility, the implants of hydrogels not only have the potential to be local drug implants for sustaining drug release over 30 days but also achieve on-demand release for the enhanced therapeutic effect. The formation of microgel colloids provides an unprecedented strategy to rearrange molecular magnets and a unique potential and possibility for magnetism enhancement. This enhancement motivates an improvement of solid tumor therapy and also supplies a force for the real implementation of the on-demand drug treatment.