Enzyme-responsive polymers for drug delivery and molecular imaging

Abstract Smart drug delivery systems that are based on environmental-responsive polymers have been developed to specifically deliver cargos to desired disease sites and controlled drug release in response to pathophysiological stimuli. Owing to the high selectivity, sensitivity, and rate enhancement of enzymes, particularly in biological processes, certain disease-associated enzymes have recently become an emerging bioresponsive trigger for smart drug delivery and diagnostic applications. In this chapter, we summarize the general strategies for designing enzyme-responsive drug delivery systems with functional polymers, focus on the enzyme-responsive polymers for therapeutic and diagnostic applications, and discuss the future directions of enzyme-responsive polymeric systems.