الفهرس 
Cover EnglishOnly 14 pages are availabe for public view
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Abstract
Most current anticancer agents do not greatly differentiate between cancerous and normal cells, leading to systemic toxicity and adverse effects. Consequently, systemic applications of these drugs often cause severe side effects in other tissues (such as bone marrow suppression, cardiomyopathy, and neurotoxicity), which greatly limits the maximal allowable dose of the drug. Nanotechnology offers a more targeted approach and could provide signi icant bene its to cancer patients. With the great development of cancer nanotechnology, various nanoparticles (NPs) of different sizes, shapes and composites provide good potential for their application in cancer diagnostics and therapy. Compared to other NPs, gold and silver nanoparticles (AuNPs and AgNPs) have great advantages in cancer applications due to their easy preparation, ef icient bioconjugation, potential non-cytotoxicity, tunable and enhanced scattering and absorption properties. The aim of this study is to engineer and design new class of nanomaterials to be used as a drug delivery system for chemotherapeutic drugs into tumor to avoid the side effects of the chemotherapeutic drugs and enhance their ef iciency. 6-Mercaptopurine (6-MP) has been used as an anticancer drug model to be attached to the metallic nanoparticles surface. 6-MP had been loaded into the spherical shape of the synthesized silver and gold NPs. The spectral and morphological studies of prepared AuNPs and AgNPs and their nanoconjugates with the anticancer drugs under study were measured via UV-VIS spectroscopy and transmission electron microscopy (HR- TEM). Our results indicate that new broad absorption band appeared upon loading the drug into the nanoparticle surface which attributed to the surface plasmonic coupling between two adjacent particles. The nature of the chemical interaction between the drug and NPs has been studied in details. Factors that affect the interaction between the drug and metallic NPs such as pH, time after mixing the drug with NPs, concentration of the drug, have been investigated. Accordingly, the binding interaction is proven to be mainly via hydrogen bonding. In vitro studies have been carried out in order to determine the effect of loading chemotherapeutic drugs into metallic NPs on human breast cancer cells (MCF-7). The data obtained from these studies shows that 6- MP@NPs is much more effective than the drug alone and the nanoparticles themselves, because the cellular uptake enhanced greatly due to loading of 6-MP on NPs. The drug action was enhanced strongly upon irradiation by LED, this attributed to the presence of strong absorption band of 6-MP@AuNPs. This indicates that these drug-gold nanoparticles conjugates could act as new series of drugs of dual effect, chemotherapeutic and photothermal effect. The second part of the thesis is devoted to investigate the antiviral effect of Silver nanoparticles (AgNPs) against Mouse mammary tumor viruses (MMTV). AgNPs were approved to be an antiviral agent against many kinds of viruses like; HIV-l, hepatitis 8, respiratory syncytial, herpes simplex type 1 and monkeypox viruses, and is still expanding to other viruses. MMTV are known with their causative role for human breast cancer. Our study indicates that silver nanoparticles show an antiviral activity against MMTV and this may open a new gate of therapeutic modality against one of the main causative of breast cancer in women.