Redox activated polymeric nanoparticles in tumor therapy

Abstract Recent progress in materials chemistry has witnessed polymeric nanoparticles being widely used to achieve targeted and controlled drug delivery. Polymeric drug–delivery systems that are activated by chemical (e.g., pH, low partial pressure of oxygen) and physical (e.g., light, ultrasound, and electrical current) stimuli have demonstrated improved in vitro and/or in vivo drug release profiles. In this chapter a brief focus is laid on the biochemical basis for oxidative stress in tumors, its role in cell-signaling, the pathophysiology of tumor vasculature and the differences in the redox-metabolism between cancer cells and nonmalignant tissues. The recent developments toward designing redox-responsive drug-delivery systems, which have been classified as polysulfide, polyselenide, quinones, metal complexes, arylboronic esters, aryl oxalate, and other miscellaneous examples are also discussed.