Synthesis and characterisation of a pH-sensitive magnetic nanocomposite for controlled delivery of doxorubicin

Abstract

We prepared a magnetic chitosan-cis-aconitic anhydride-doxorubicin nanocomposite, denoted by MCS-CAA-DOX. Chitosan (CS) was linked to magnetic nanoparticles (Fe₃O₄) to decrease cytotoxicity of the composite and provided a large number of reactive sites for coupling of drug molecules. DOX was attached to the magnetic chitosan (MCS) via a pH-sensitive linker, cis-aconitic anhydride, which hydrolyses in the acidic lysosomal environment to allow pH-responsive release of DOX. The prepared nanocomposites were within 15 nm and had good superparamagnetic properties. The loading rate of DOX was up to 83%. It was found that nearly 88% DOX was released within 60 h at pH 5.0, compared with only 29% at pH 7.4.

• Chitosan
• drug delivery
• pH-sensitive
• magnetic nanocomposites

Declaration of interest

The authors are grateful for the financial support of National Natural Science Foundation of China (Nos. 50602024 and 50972060), the Scientific and Technical Supporting Programs of Jiangsu province (BE2012758) and the Scientific Research Fund from NJUST Research Funding (No. 2010ZDJH06), the Fundamental Research Funds for the Central Universities (No. 30920130112003).