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
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.
1. Y. Cheng et al. Advanced Drug Delivery Reviews 2014, 66: 42-57.
2. G. Chen et al. Biomaterials 2015, 47: 41-50.