Investigation of the effectiveness of silver nanoparticules produced by green synthesis method in cancer

In this PhD thesis, the plants of Ca (pepper- Capsicum annuum ) and SM (thistle- Silybum marianum ) were used as reducing agents in order to obtain silver nanoparticles ( Ag NP) via green synthesis method. The formation kinetics of ( Ag NP) ' s were stated by UV- vis Spectrophotometer and the morphological properties by Transmission Electron Microscope (TEM). The Ag NP's synthesized with different molar concentrations of AgNO3 solutions (1, 2 and 4 mM) in aqueous solutions of SM and CA plants exhibit surface plasmon resonance (SPR) peaks ranging from 391,5-426 nm. These are the typical absorbance peaks that belong to Ag NP's. According to TEM images, Ag NPs were found to have a spherical shape in the 2,5-24 nm size range. The smallest Ag NP sizes were obtained from a mixture of 1 mM AgNO3- thistle and the NP sizes were 2,4±1 nm The cytotoxicity of MCF-7 cells, which are incubated for 24 and 48 hours with different mass concentrations of Ag NPs was determined by MTT test. According to MTT results, Ag NPs showed dose-dependent cytotoxicity and IC50 doses; at the end of the 24-hour incubation period 45.6 µg/ml in pepper extract and 42 µg/ml in thistle; similarly, after 48 hours of incubation, it was calculated as 37.5 µg/ml and 38 µg/ml in pepper and thistle, respectively. It was determined that the radio-sensitivity of MCF-7 cells incubated with Ag NPs irradiated with 6 MV energy X-rays at a radiation dose of 6 Gy was increased. It was observed that both plant extracts alone were not radio-sensitive and, although they were synthesized from different plants, the radiation sensitivities of all Ag NPs gave similar results.