Construction of nanomaterials based on pH-responsive polymers for effective tumor delivery

Polymer-based nanomaterials can deliver antitumor reagents to tumor tissues effectively due to the enhanced permeation and retention (EPR) effect. To further improve the tumor delivery efficacy, a targeting moiety should be installed in the polymer building blocks. In this regard, an acidic pH is one of the characteristics of tumor sites, whereby polymers that respond to acidic conditions would realize the construction of tumor-targeted nanomaterials. In this review, we explain the rationale strategies for the design of functional polymers with responsiveness to a low tumor pH and describe examples of smart nanomaterials designed for selective tumor delivery.