Stimuli-responsive polymers for biomedical applications

Polymeric biomaterials that respond to external or internal stimulations have gained interest in medicine. These properties are patented to be utilized in the biological area as distinct excellence. Specifically, in nanomedicine, regenerative medicine, drug delivery, and biopolymers need to be controlled in a biological system. In the body, a biopolymer could be designed to activate in a specific location and time while facing biological components and specific chemical or physical circumstances. For this aim, stimuli-responsive polymers are suitable choices as biological controllers. Recently, these polymers have been used widely as biomaterials and exhibited promising results. Stimuli-responsive polymers respond sharply to small changes in the biological environment and after removing the stimuli, the system can return to its primary state. In this chapter, we classified stimuli-responsive polymers into endogenous sources (internal stimuli) and exogenous sources (external stimuli). Endogenous stimulators are mostly spontaneous activators for the polymers due to the sensitivity of the polymer to these stimulators. On the other side, exogenous stimulators are mostly unspontaneous activators as they need to be activated by external sources and by adjusting circumstances.