pH-Sensitive Polymeric Nanoparticles as Carriers for Cancer Therapy and Imaging

Safe and efficient diagnosis and therapy of cancers are important and of great interest these years. Multifunctional polymeric nanoparticles incorporating therapeutic and imaging agents are powerful tools for simultaneous therapy and diagnosis (theranostics). The most frequently used biodegradable polymers in drug-delivery systems (DDSs) are polycaprolactone (PCL), poly(glycolic acid) (PGA), poly(lactic acid) (PLA), and their copolymers. This chapter discusses different types of pH-sensitive polymers and the DDSs based on them. The synthesis of pH-sensitive polymers and the fabrication and assessment (in vivo and in vitro) of pH-sensitive DDSs are addressed. Polymers with fine and controllable structures are very important for biomedical applications. The availability of numerous techniques for synthesizing polymers affords the ability to prepare polymers with diverse fine structures, allowing DDSs to be fabricated for different purpose by choosing the appropriate polymers.