الفهرس 
cover eOnly 14 pages are availabe for public view
 |  | from | 116 |  |  |
| | | from | 116 | | |
Abstract
Hepatocellular carcinoma (HCC) is one of the most known fatal malignancies. Globally, HCC is the fifth common cancer and it is the second causing death with 745,500 per year due to its poor prognosis. chronic infection with hepatitis B virus (HBV) and hepatitis C virus (HCV), fatty liver disease, exposure to dietary aflatoxin, alcohol-induced cirrhosis, smoking, obesity, diabetes, and iron overload have been frequently reported to precede the development of HCC. Currently, there is no effective treatment for advanced stages of HCC due to its aggressive nature and poor survival rate. A green method was used for producing gold nanoparticles (Au NPs) using chitosan as a natural cationic, biodegradable and biocompatible polymer. In an attempt to mitigate the side effects of anti-cancer drug, 5-fluorouracil (5-FU), through reducing drug doses in photothermal therapy, the formed positively-charged chitosan-wrapped Au NPs were used as a drug delivery system for negatively charged 5-FU to HepG2. Au NPs as well as 5-FU@Au nanocomposites were characterized by UV-VIS spectroscopy, particle size, zeta potential, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and High-Performance Liquid chromatography (HPLC). The chitosan concentration was shown to be an important parameter for optimizing the dispersion of Au NPs and 5-FU@Au nanocomposites over long time. This stability offers the 5-FU@Au nanocomposites as promising strategy for cancer treatment with reduced drug doses in photothermal therapy. The cytotoxicity effect of free 5-FU and 5- FU@AuNPs nanocomposites was studied. Compared with the free 5-FU, the concentration of 5-FU@Au nanocomposites required to attain 50٪ of inhibition growth rate was found to be less by two and seven folds in absence and presence of laser irradiation, respectively. On the other hand, chitosan nanoparticles were considered to be a good candidate for targeted and localized drug delivery to cancer cells. The surface positive charge of chitosan nanoparticles, as well as their mucoadhesive properties enabled it to be adhered to the mucus membrane and release the payloaded drug in sustained release manner. It was found that the concentration of ChNPs-5-FU required to attain 50٪ of inhibition growth rate was lower than that of free 5-FU in absence of laser radiation and was much lower in presence of laser radiation.