چكيده به لاتين
Recently nanocomposites with hybrid characteristics have been developed in biological and medical fields especially in cancer therapies, drug delivery, in-vivo optical and magnetic resonance imaging, bio-labeling and DNA alteration. Therefore magnetic, optical and plasmonic nanoparticles have been widely investigated. Plasmonic nanoparticles are useful for improving optical and anti-bacterial properties of nanoparticles.
For this purpose Nano Zero Valente Iron (nZVI) with a Polyvinylpyrrolidone (PVP) shell was synthesized from Iron sulfate and NaBH4 by chemical reduction route and ultrasound assistance. Cytotoxicity of nZVI was evaluated in L929 Fibroblast cells and the results showed that these nanoparticles showed almost no toxicity up to 2000 μg⁄ml of particle loading and cell death in the most toxic sample was only 25% in 3000 μg⁄ml of concentation. Al-doped ZnO nanoparticles was synthesized by hydrothermal route from Zinc Acetate and NaOH precursors, the synthetic parameters such as the temperature, time and pH and dopant concentration were optimized and the variation in cytotoxicity of Al-doped ZnO nanoparticles in comparison to ZnO nanoparticles was evaluated in MCF-7 breast cancer cells. The concentrations needed for 80% cell death were 125 μg⁄ml and 250 μg⁄ml for ZnO and Al-doped ZnO nanoparticls.
Fe/SiO2/ZnO/Ag nanocomposite was synthesized by routes above in sequence. First the polymeric shell on nZVI nanoparticles was changed to SiO2 in order to make it tolerant in higher temperatures of hydrothermal procedure. Fe/SiO2 Particles were synthesized by chemical reduction; Second, ZnO particles was formed on the Fe/SiO2/ZnO particles and finally Ag nanoparticles were decorated on nanocomposite by a chemical precipitation route from AgNO3 precursor. In cytotoxicity study of Fe/SiO2/ZnO/Ag nanocomposite, 31 μg⁄ml of particles were enough to kill 80% of MCF-7 breast cancer cells.
Structural, microstructural, surface properties of nanoparticles were as tested with XRD, FE-SEM and TEM, FTIR, RAMAN spectroscopies. Evaluation of magnetic and optical properties were measured with VSM, UV-Vis and PL techniques. In addition, variations and influence of different components of nanocomposite on each other were studied.
