In Situ Formation of pH-Sensitive Polymer-Gold Nanohybrid System for Cancer Treatments

In situ formation of pH-sensitive polymer-gold nanohybrid system for cancer treatments

Wenjing Lin, Na Yao, Lijuan Zhang*

School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, P. R. China

E-mail: lin.wenjing@mail.scut.edu.cn

Tremendous polymer materials have been intensively exploited as innovative nanovectors for cancer therapy in recent years. The current trend focus on the elaboration of multi-functional nanovectors which can reach to the diseased site, release a drug in a controlled manner and act as an imaging agent for both targeted therapy and diagnosis^[1,2]. Most of these nanocarriers can take advantage of each function and integrate synergistically into one single system, which would otherwise be difficult to accomplish in a single-component system.

In this study, we have designed an in situ formed pH-sensitive polymer-gold nanohybrid system as a promising dual-functional nanoplatform for antitumor drug delivery and CT imaging. The general approach is to synthesize b-CD-(PLA-PDMAEMA-PEtOxMA)₂₁ by the combination of ROP and ARGET ATRP techniques), employ the polymer as template for in situ formation of Au nanoparticles without any reducing agent, and encapsulate doxorubicin (DOX). The formed b-CD-(PLA-PDMAEMA-PEtOxMA)₂₁/Au nanoparticles were characterized by UV-vis, DLS, TEM, microplate reader and CT imaging system. Varying block ratios, polymer/Au salt molar ratios and pH, they showed controllable maximum absorption wavelengths, uniform sizes, excellent colloidal stability, negligible cytotoxicity and enhanced X-ray attenuation property. After the loading of DOX, DOX@b-CD-(PLA-PDMAEMA-PEtOxMA)₂₁/Au revealed pH-controlled release because of the protonation of the PDMAEMA, high accumulation and good antitumor activities confirmed by in vitro release test and biodistribution studies. Therefore, we believe this pH-sensitive polymer-gold nanohybrid system can be used as a latent nanocarrier for cancer theranostic application.

References

1. Y. Cheng et al. Advanced Drug Delivery Reviews 2014, 66: 42-57.

2. G. Chen et al. Biomaterials 2015, 47: 41-50.