Thesis (M.Sc.)--Chulalongkorn University, 2009

Gold nanoparticle (AuNP) is a stable and inert metal nanoparticle. AuNP has been used as biosensors, drug/gene delivery devices and contrast agents because of its surface functionalization. AuNP can be tailored with biomolecules such as DNA, protein, carbohydrate, drug and fluorescent dye. However, the previous studies show that AuNP toxicity data are conflicted. Hence, this study aims to evaluate the toxicity of AuNP on HeLa cells including cell viability, cellular/intracellular organelles morphology, AuNP localization and mitochondrial gene expression. HeLa cells were incubated with various concentrations of gold nanoparticles for 1, 2 and 3 days. Cells were evaluated for cellular/intracellular organelles morphology, localization of AuNP, cell viability and mitochondrial gene expression using light microscope, transmission electron microscope MTT assay and RT-PCR, respectively. This study demonstrated that 100 µg/mL AuNP decreased cell viability and affected cellular morphology. However, intracellular organelles morphology was not irregular. The aggregated AuNPs were mainly entrapped in the endosome and localized in the cytoplasm. Furthermore, the mitochondrial gene expression level was unchanged.