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Meena, Karunakaran Sulochana
- Comparison of Photodynamic Activities of Ag@Tio2 and Au@Tio2 Core-Shell Nanoparticles in Human Erythrocytes
Authors
1 Department of Chemistry, Queen Mary’s College, Chennai, IN
2 Department of Chemistry, Adhiparasakthi College of Science, Kalavai, IN
3 Department of Physics, Anna University, Chennai, IN
Source
Asian Journal of Research in Chemistry, Vol 4, No 3 (2011), Pagination: 387-391Abstract
Core-shell type nanoparticles namely Ag@TiO2 and Au@TiO2 were prepared by one pot simultaneous reduction of HAuCl4 and hydrolysis of Ti(IV) isopropoxide. They were characterized by absorption and fluorescence spectroscopy, XRD, HR-TEM and AFM techniques. XRD patterns show the presence of anatase form of TiO2 and the noble metals. Since the catalytic properties of the oxide surfaces modified with the metal core especially photo catalysis is an important aspect and considering the fact that erythrocytes serve as model cells to the molecular mechanism of PDT, the photohemolysis was studied using these core-shell type NPs viz. Ag@TiO2 and Au@TiO2. Their photodynamic activities were compared. The effect of scavengers viz., GSH and NaN3 showed that there is a considerable amount of reactive oxygen species formation which are responsible for cell death. The detailed mechanism has been discussed.
- Gold–Nanoparticles A Novel Nano-Photosensitizer for Photodynamic Therapy
Authors
1 Department of Chemistry, Queen Mary’s College, Chennai, IN
2 Department of Physics, Anna University, Chennai, IN
3 Department of Chemistry, Adhiparasakthi College of Science, Kalavai, IN
Source
Asian Journal of Research in Chemistry, Vol 4, No 1 (2011), Pagination: 58-63Abstract
Gold Nanoparticles (GNPs) of size below 5 nm were prepared by reduction of Chloroauric acid using sodium citrate and NaBH4 and characterized. High resolution transmission electron microscopic measurements revealed their size less than 5nm. Their photodynamic action was tested in human erythrocytes. The percent hemolysis showed a decrease in PDA above a particular GNPs concentration. The study of the effect of scavengers GSH and NaN3 showed formation of a considerable amount of superoxide anion and singlet oxygen that caused cell death. The detailed mechanism is discussed. GNPs being nontoxic serve as proper substitute for the conventional photosensitizers such as organic dyes.