X-ray optics of gold nanoparticles.
Gold nanoparticles have been investigated as contrast agents for traditional x-ray medical procedures, utilizing the strong absorption characteristics of the nanoparticles to enhance the contrast of the detected x-ray image. Here we use the Kramers-Kronig relation for complex atomic scattering factors to find the real and imaginary parts of the index of refraction for the medium composed of single-element materials or compounds in the x-ray range of the spectrum. These complex index of refraction values are then plugged into a Lorenz-Mie theory to calculate the absorption efficiency of various size gold nanoparticles for photon energies in the 1-100 keV range. Since the output from most medical diagnostic x-ray devices follows a wide and filtered spectrum of photon energies, we introduce and compute the effective intensity-absorption-efficiency values for gold nanoparticles of radii varying from 5 to 50 nm, where we use the TASMIP model to integrate over all spectral energies generated by typical tungsten anode x-ray tubes with kilovolt potentials ranging from 50 to 150 kVp.
Renat R
RR
Letfullin
Colin E W
CE
Rice
Thomas F
TF
George
D065638:Absorption, Radiation; D003198:Computer Simulation; D006046:Gold / Q000737:chemistry* / Q000528:radiation effects; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D008956:Models, Chemical; D010316:Particle Size; D012542:Scattering, Radiation; D014965:X-Rays
D006046:Gold