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.

由于增强的渗透和保留（EPR）效应，基于聚合物的纳米材料可以有效地将抗肿瘤试剂输送到肿瘤组织。为了进一步提高肿瘤递送功效，应该在聚合物构建块中安装靶向部分。在这方面，酸性 pH 值是肿瘤部位的特征之一，从而响应酸性条件的聚合物将实现构建肿瘤靶向纳米材料。在这篇综述中，我们解释了设计对低肿瘤 pH 有反应的功能聚合物的基本原理，并描述了用于选择性肿瘤递送的智能纳米材料的例子。