Biocompatible Au nanoparticles with surfaces modified by PEG (polyethyleneglycol) were developed in view of possible applications for the enhancementof radiotherapy. Such nanoparticles exhibit preferential deposition at tumorsites due to the enhanced permeation and retention (EPR) effect. Here, wesystematically studied their effects on EMT-6 and CT26 cell survival ratesduring irradiation for a dose up to 10 Gy with a commercial biological irradiator(E average = 73 keV), a Cu-Kα 1 x-ray source (8.048 keV), a monochromatizedsynchrotron source (6.5 keV), a radio-oncology linear accelerator (6 MeV) anda proton source (3 MeV). The percentage of surviving cells after irradiationwas found to decrease by ∼ 2–45% in the presence of PEG-Au nanoparticles([Au] = 400, 500 or 1000 μM). The cell survival rates decreased as a functionof the dose for all sources and nanoparticle concentrations. These resultscould open the way to more effective cancer irradiation therapies by usingnanoparticles with optimized surface treatment. Difficulties in applying MTTassays were also brought to light, showing that this approach is not suitable forradiobiology.
Date:
2010-02
Relation:
Physics in Medicine and Biology. 2010 Feb;55(4):931-945.
