Stimuli-Responsive Polymeric Systems for Smart Drug Delivery

This chapter provides a general description of smart drug delivery systems (DDSs) based on the use of stimuli-responsive polymers. Smart DDSs have the distinctiveness of carrying out the release of therapeutics at the target sites in a spatially controlled manner. This means that the drug is released with suitable speeds exclusively at the site of action. Specifically, smart DDSs ensure that the drug is not freely extravagate during blood circulation, and only released at specific sites (organs/tissues) where these nanocarriers accumulate through an active or passive targeting strategy. Various polymers-based nanomaterials offer new opportunities for the preparation of smart DDSs due to their unique nanoscale properties and specific bio-functions. In this way, there is a special type of polymers called ‘stimuli-responsive’, ‘intelligent’, ‘smart’ or ‘environmental-sensitive’ polymers, because they have the particularity of responding to small physical or chemical stimuli leading to a macroscopic alteration in their structure/properties. The basis of the different stimulus-sensitive polymers used in the preparation of intelligent DDSs will be presented in the different sections of this chapter taking into account the stimulus that trigger polymer alteration and their specific applications in drug delivery.