الفهرس 
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Abstract
The aim of the work: was to investigate the toxicity effects of the prepared gold and silver nanoparticles on ovary of the female adult rats and to study the photostability of the prepared nanoparticles. Materials and Methods: Sixty female Wister albino rats, their age ranges between 12 , and 14 weeks, weighing l40-160g were classified into 10 groups, 6 animals were assigned for each group. The control animals received the same dose of physiological saline for the same period of each study. The small dose of gold nanoparticles was 40 ug/kg while large dose of gold was 400 ug/kg, The small dose of silver nanoparticles was 30 mg/kg while the large dose of silver nanoparticles was 300 mg/kg. All doses were given orally. Duration of the study was 2 and 4 weeks. Rats were sacrificed by cervical dislocation on the next day of the last dose and then the ovaries were removed. Samples for light microscopy were fixed in 10% neutral buffered formalin and examined after staining with Haematoxylin and Eosin (H&E) stains and Masson’s Trichrome stain. Also, staining was performed on formalin fixed paraffin embedded specimens for Caspase 3. Samples for electron microscopy were fixed with 3% cold glutaraldehyde for two hours for examination. The photostability of prepared gold and silver nanoparticles has been studied by irradiation with UV light of 254nm and light emitting diode (LED) of 490nm. The absorption spectra of the solution have been measured before exposure, and then it is irradiated. The absorption spectra have been measured after irradiation at different time intervals to monitor any change in spectra. Results: The gold groups showed insignificant decrease in mean body weight gain except the group with high dose and longest duration, it showed highly significant decrease in body weight gain when compared with the mean body weight gain in corresponding control group. While the decrease in mean body weight gain in all silver groups was highly significant when compared with mean body weight gain in the corresponding control groups. The results of light microscope in gold and silver groups revealed that all groups showed congested blood vessels in the stroma with mononuclear cell infiltration and areas of congestion in the stroma that increase with the increase of dose and duration. Excess deposition of collagenous bundles was seen in all groups which indicate the presence of fibrosis. Positive reaction for caspase3 in ovarian tissue in all groups started from very weak and mild then the reaction increased to moderate and strong with the increase in dose and duration in which indicate the presence of cell apoptosis. The results of electron microscope revealed that all groups of gold and silver showed congested blood vessels in the stroma and areas of congestion in the stroma. Also, gold nanoparticles were observed in the stroma of all groups. Excessive vesicles, saturated lipid droplets, vacuoles were observed in the cytoplasm of some gold groups, granulosa cells with shrinked nuclei, separated granulosa cells and destructed mitochondria were also seen. Silver nanoparticles deposits were seen on the wall of lipid droplets and inside secondary lysosome. Also, separated granulosa cells and red blood cells between theca interna cells were observed. Granulosa cell with pyknotic nucleus and eosinophils cell in the stroma with its specific granules were also seen in some silver groups. Multiple vesicles and dilated smooth endoplasmic reticulum were observed. The gold nanoparticles showed no changes in the optical density and were stable in shape after irradiation by UV-light and LED. The irradiation of silver nanoparticles using UV light and LED showed slight aggregation of the silver nanoparticles. Conclusion: Gold and silver nanoparticles showed evidences of congestion, bleeding, inflammation, fibrosis and apoptosis in cells of the ovary in all examined doses and further studies are required to determine the appropriate nontoxic dose and duration.