Gold-Curcumin Nanostructure in Photo-thermal Therapy on Breast Cancer Cell Line: ۶۵۰ and ۸۰۸ nm Diode Lasers as Light Sources

Background: Au nanoparticles (AuNPs) exhibit very unique physiochemical and optical properties, which now are extensively studied in a range of medical diagnostic and therapeutic applications. AuNPs can be used for cancer clinical treatment with minimal invasion. On the other hand, curcumin is a polyphenol derived from turmeric which is used for medical purposes due to its anti-cancer, anti-microbial, anti-oxidant and anti-inflammatory properties. Despite these potential properties of curcumin, its usage is limited in medicine due to low solubility in water. Conjugation of curcumin to AuNPs (Au-Cur nanostructure) can be increasing its solubility. Photo-thermal therapy (PTT) is a novel kind of cancer treatment which involves two major components: laser and photo-thermoconversion agents. Materials and Methods: Here, diode lasers emitting ۸۰۸ nm and ۶۵۰ nm were utilized as light sources, and synthesized Au-Cur nanostructure was applied as a photo-thermo conversion agent. UV-vis absorbance spectroscopy and dynamic light scattering (DLS) were applied to study the maximum absorption of particles, size stability of the samples and their zeta potential. The synthesized Au-Cur nanostructure under irradiation of laser is used for PPT on ۴T۱ cells. The cytotoxicity activity of Au-Cur nanostructure and laser irradiation on ۴T۱ cells was evaluated by MTT assay. Results: Synthesized Au-Cur nanostructure showed λmax at ۵۴۰ nm and a mean hydrodynamic diameter of ۲۵.۸ nm. ۴T۱ cells were exposed to an ۸۰۸ nm diode laser (۱.۵ W cm۲, ۱۰ min) in the presence of different concentrations of Au-Cur nanostructure. Next, ۴T۱ cells with Au-Vur nanostructure were exposed to diode laser beam (۶۵۰ nm, ۱.۵ W cm۲) for ۱۰ min. The results revealed that Au-Cur nanostructure under laser irradiation of ۸۰۸ nm more decreased cell viability of ۴T۱ cells compared to laser irradiation of ۶۵۰ nm. Conclusion: It was concluded that combining an ۸۰۸-nm laser at a power density of ۱.۵W/cm۲ with Au-Cur nanostructure has a destruction effect on ۴T۱ breast cancer cells in vitro experiments compared to laser irradiation of ۶۵۰ nm.