Chitosan Nanoparticles as Drug Delivery Systems

The goal of the present work is to synthesize chitosan-coated superparamagnetic iron oxide nanoparticles (CS SPIONs) for doxorubicin (DOX) delivery for cancer theranostics. The CS SPIONs will be loaded with the anticancer drug DOX because it is largely used clinically for different cancers types. In this work chitosan nanoparticles (CS NPs) and iron oxide nanoparticles were synthetized by ionic gelation and thermal decomposition techniques, respectively. Chitosan depolymerization was performed to be used different molecular weights (474 – 39 kDa) to produce CS NPs with different diameters. Magnetic stirring and pH influence were also studied. Dynamic Light Scattering (DLS) measurements indicate that was obtained different nanoparticles diameters, approximately the lowest diameters were around 100 nm and 9 nm for CS NPS and iron NPs respectively. Then, CS SPIONs were formed. Synthetized nanoparticles were characterized by (DLS), UV-Visible (UV-Vis), Fourier Transform Infrared Spectroscopy (FTIR) and Transmission Electrons Microscopy (TEM). Superconducting Quantum Interference Device (SQUID) and magnetic hyperthermia studies indicate that this nanoparticles show a superparamagnetic behavior and the ability to generate heat. These characteristics are essential to be possible to use these nanoparticles in biomedical applications such as contrast agents for MRI, magnetic drug delivery, cancer diagnostics and treatment. The DOX delivery studies indicate that the drug release depends on pH and in the first 10-20 hours the majority of drug is released. Finally, the in vitro cell viability and proliferation studies were conducted using the Vero cell line. These studies indicate that the CS SPIONs synthetized in the present work are non-toxic up to the CS SPIONs concentration of 1.25 mg/ml. Considering all the studies conducted in this work, it can be concluded that the nanoparticles synthetized possess the necessary characteristics to be used in biomedical applications