Chapter 8 - Stimuli-responsive micelles: A nanoplatform for therapeutic and diagnostic applications

Abstract

Since they were first introduced to drug delivery a little more than three decades ago, polymeric micelles have acquired a significant place among the newer drug delivery systems. From the early concept of nanoassemblies of simple di-block linear amphiphilic copolymers to the highly-evolved stimuli-responsive micelles being explored for targeted anticancer therapy, gene delivery, diagnostics, and recently for theranostic applications, polymeric micelles have traversed a long way. Stimuli-responsive polymeric micelles are derived from the family of smart polymers which show characteristic alterations in properties when subjected to specific environmental conditions, such as those of pH, temperature, photons, redox potential, ultrasound, or even enzymes. This so-called response to the stimulus, is used strategically to achieve one or more of several objectives including prevention of drug release outside of the target site, triggering of site specific or “on demand” release of therapeutic agents, increased interaction with the target cell, etc. This chapter presents a detailed review of the various classes of stimuli-responsive micelles, the strategies in their design, and the current advancement with respect to their drug delivery and diagnostic applications.