Stimuli-Responsive Polymers for Brain Delivery

Stimuli-responsive biomaterials are unique functional polymers that are used to achieve desirable behavior of novel pharmaceutical dosage forms like a phase transition in situ or in vivo, on-demand drug release, programmed and targeted drug delivery, shape memory polymers, etc. in response to the environmental triggers. Innovative decades of medical sciences have widely explored the potential of these smart polymers to design smart drug delivery systems to combat various life-threatening chronic disorders like cancer, brain disorders, etc. and for tissue engineering, bone/tissue regeneration, etc. Most of the endogenous (temperature, pH, ROS, enzyme, ionic concentration, oxidation-reduction reaction, etc.) and exogenous (temperature, light, electric impulse, magnetic field, ultrasonic waves, etc.) stimulus act as triggering factors for such polymers and induce change in their physical or chemical properties. Utilizing such features, the novel formulations could be designed for controlled, prolonged, targeted, programmed release of drug, locating the tumor or inflamed/diseased tissues, tissue engineering, and to approach critical areas like the brain. The stimuli-responsive polymers found wide application in brain delivery due to their unique properties of prolonged and targeted drug delivery and their ability to improve the drug pharmacokinetics. This chapter compiles different types of smart functional polymers and their application in the design of novel formulations for enhanced brain delivery of drug and diagnostic agents.