pH-Sensitive Nanoscale Polymers: Highly Efficient Systems for DOX Delivery in Cancer Treatment

Recently, many stimuli-responsive drug delivery systems based on biodegradable and biocompatible polymers have been introduced for controlled release of anticancer drug Doxorubicin. The main role of polymers in these systems is to provide high loading of Doxorubicin and then control the release of the drug in low pH-media. Polymeric micelles and nanoparticles such as magnetic particles, silica and graphene oxide covered with smart polymers include two main categories of Dox-controlled release systems. Herein, we review aforementioned systems which have been used for Doxorubicin release through different response of the system in terms of pH including: swelling or expansion of the polymeric chains, pH-sensitive bond cleavage and loss of electrostatic interactions between the drug and system. The mechanism of drug loading, drug release, advantages and disadvantages of each system are fully discussed.