مجله علوم و فنون هستهای (Aug 2013)
The Radiosensitivity Effect of Folic Acid Conjugated Gold Nanoparticles in Superficial Radiation Therapy of MCF-7 Cancer Cell Line
Abstract
Recent dvances in nanotechnology have enabled us to accumulate high atomic-number nano-materials, such as gold nanoparticles (GNPs), in tumor cells selectively using different techniques and take the advantage of the dose enhancement factor resulting from the presence of such high-Z elements as the vicinity of cancerous cells as a radiosensitizer agent. In this research, the GNPs with an average diameter of 50nm were synthesized and conjugated with folic acid. Different concentrations of this nanoconjugate were incubated with MCF-7 cells for 24 hours and its cytotoxicity was investigated. The results showed that increasing the nanoconjugate concentration up to a critical amount, affects the cells viability. The radiosensitizing effect of the folate nanoconjugate, with a concentration of 50μg/mL, on the MCF-7 cells was assessed under 2Gy of x-ray radiation, generated by an orthhovoltage radiotherapy machine, at various energies of 120, 180, 200 kVp, using the MTT assay. Significant differences in the cell survival were noted among the groups exposed to x-ray radiation with and without the nanoconjugate. A maximum dose enhancement factor of 1.34±0.03 was obtained for the 180kVp X-ray beam. The findings enable us to decrease by one third of the prescribed dose while having the same level of damage to cancer cells. Also, this dose reduction results in lower exposure to the normal tissues located close to the target.
