Synthesis and Evaluation of Gold Nanoparticles/Nanorods to Use in Plasmonic Photothermal Therapy

Introduction: Photothermal therapy is a method of cancer treatment that plasmonic nanoparticles are used to convert infrared light into local heat. Due to the plasmonic properties of gold nanoparticles, this compound was used as a contrast agent. The aim of this study was to synthesize gold nanoparticles with different conjugations for photothermal therapy. Methods: This research was an experimental study. The method used for the synthesis of spherical and rod gold nanoparticles in this research was the Seeding Method. The nanoparticles were then conjugated with various compounds such as rifampicin, quercetin and RGD. Then, the physical and chemical properties of nanoparticles were determined by DLS, UV-Vis and TEM methods. Cytotoxicity test was also performed on MCF-7 ((Michigan Cancer Foundation-7)) cell line. Cell viability was calculated using prism software. Differences were compared by analysis of variance (ANOVA) using SPSS version 16 software. Results: In the UV test, two-peaked rod nanoparticles were observed in the range of 523 and 738 nm, and in the case of spherical nanoparticles at 535 wavelengths, which indicates the correct synthesis without impurities and with the appropriate size .In the cell test, a decrease in cell viability was observed compared to the control group. In the first 24 hours, spherical nanoparticles had the highest lethality to the point that at a concentration of 20 μg / ml, it had almost 50% lethality. In addition, after 48 hours at low concentrations, rod nanoparticles showed better results, so they were more suitable. By targeting these nanoparticles to specific cancer cells, in addition to being used to kill cancer cells, the effect of these nanoparticles on healthy cells can be prevented. By conjugating different compounds on the surface of these nanoparticles, cell uptake can also be increased and cancer cells can be killed using photothermal therapy. Conclusion: According to the results obtained in this study, it seems that low-concentration of gold nano-rods are more suitable for photothermal therapy.