Smart Polymeric Micelles with Aggregation-Induced Emission and pH-Responsive Fluorescence Color Change Behavior for Bioimaging and Cancer Therapy

In this paper, a multifunctional polymer BT-PGA-TPE-HNPE was designed and synthesized by modifying γ-polyglutamic acid (γ-PGA) with biotin, the tetraphenylethylene derivative O-TPE-HNPE and an acid-sensitive imine bond. The polymer was used to fabricate paclitaxel (PTX)-loaded micelles. As expected, the BT-PGA-TPE-HNPE micelles demonstrated strong AIE characteristics, fluorescing yellow under normal conditions and blue in acidic settings. Moreover, the drug was specifically released under acidic conditions. In vitro and in vivo tumor suppression experiments showed that the micelles had enhanced antitumor activity with minimal systemic toxicity. The BT-PGA-TPE-HNPE micelles had wide application prospects in the fields of chemotherapy and bioimaging.