title: Evaluation of the effects of gold nanoparticle shape and size on contrast enhancement in radiological imaging.
abstract: There has been increasing interest in the use of a nanoparticle-based media as a contrast-enhancement agent in medical imaging, particularly with gold Nanoparticles in radiography. Particularly attractive, is the prospect of modifying the surface of these materials with monoclonal antibodies to preferentially bind the nanoparticles to tumour sites. These materials differ from conventional molecular agents in their ability to be modified with cell specificity, or tailored for size and shape for maximum uptake. We investigated the consideration that quantum confinement electronic effects in nanometre-sized metals might have an effect on the integrated photon attenuation of gold atoms; in the same manner as these materials affect X-ray absorption and scattering as seen in X-ray absorption spectroscopy. This experiment has been designed to identify any effect on contrast enhancement that might result from employing gold nanoparticles with a variety of sizes. Spherical particles and nanorods were synthesised for this application. Image contrast enhancement was quantified by contrast-to-noise ratio in computed radiography. Results are consistent with existing measurements of gold nanoparticle contrast enhancement in radiography. No significant variation in attenuation depending on particle size was observed. Findings indicate that nanoparticle-based contrast agents in the size range 4-30 nm-can be synthesised for maximum stability or cell specificity (directed cellular uptake) without consideration of effect of size on contrast enhancement.
authors.affiliation: School of Medical Sciences, RMIT University, Bundoora, Melbourne, VIC, Australia.
authors.forename: Price
authors.initials: P
authors.lastname: Jackson
authors.forename: Selvakannan
authors.initials: S
authors.lastname: Periasamy
authors.forename: Vipul
authors.initials: V
authors.lastname: Bansal
authors.forename: Moshi
authors.initials: M
authors.lastname: Geso
mesh_terms: D000704:Analysis of Variance; D003287:Contrast Media / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011856:Radiographic Image Enhancement / Q000379:methods; D011859:Radiography / Q000379:methods*; D013329:Structure-Activity Relationship
chemical_list: D003287:Contrast Media; D006046:Gold