The Study Of Hyaluronic Acid-derivatized Magnetic Carbon Nanotubes Based Drug Delivery System

Carbon nanotubes (CNTs) have shown great potentials in many disciplines，especially in the aspects of drug delivery. However, the insolubility in most solventsand high cytotoxic of pristine CNTs limited their potential utilities in biomedicine.The purpose of this project is to get magnetic CNTs as well as improve their water-solubility by the use of Fe3O4and Hyaluronic acid. And then a therapy agentDocetaxel (DTX) was adsorbed onto the functionalized CNTs to develop CNTs-Fe3O4-HA/DTX magnetic targeted drug delivery system. The distribution of DTX inmice and growth inhibition of tumor both in vivo and in vitro were tested toinvestigate therapeutic efficacy of the targeted drug delivery system.In this study, a CNTs derivative, Fe3O4and hyaluronic acid derivatized CNTs(CNTs-Fe3O4-HA) was synthesized and then characterized by fourier transforminfrared spectroscopy (FT-IR), dynamic laser light scattering (DLS), transmissionelectron microscopy(TEM),vibrating sample magnetometer(VSM) and so on, whichwas proved to be of high aqueous solubility, stability， superparamagnetic andbiocompatibility.After that, a therapy agent Docetaxel (DTX) was adsorbed onto thefunctionalized CNTs to develop CNTs-Fe3O4-HA/DTX magnetic targeted drugdelivery system. The prescription craft was optimized through single factorexperiment concerning reactant ratio, ultrasonic time, ultrasonic power andfrequency on the impact of loading capacity, and the best preparation technologywas determined. CNTs-Fe3O4-HA/DTX was characterized by dynamic laser lightscattering (DLS) and so on, which was proved to be potential in drug loading, goodstability in commonly used biological medium and appropriate particle size andpotential distribution.SRB experiments indicated that CNTs-Fe3O4-HA had no obvious toxicity onMCF-7cells. Compared with DTX, CNTs-Fe3O4-HA/DTX produced a higherinhibition efficacy on MCF-7cells when treated for72h. Besides, CNTs-Fe3O4-HAcan also transfer into the cell through the membrane of MCF-7cells. Distribution of DTX and growth inhibition of tumor in the mice with S180sarcoma were carried out. Distribution test showed that CNTs-Fe3O4-HA/DTX hada tumor targeting tendency，which can be more evident with a external magneticfield on the tumor. Meanwhile，the inhibition of CNTs-Fe3O4-HA on mice S180sarcoma was tested with DTX as control, the result showed CNTs-Fe3O4-HA/DTXwith a external magnetic field had a better therapeutical effect.