title: Negligible absorption of radiofrequency radiation by colloidal gold nanoparticles.
abstract: We report quantitative measurement of heat generation in Au-nanoparticle colloidal solutions induced by radiofrequency (RF) electromagnetic waves (13.56 MHz; 25 W). The possible role of Au nanoparticles in RF heating was systematically investigated by separating the metal nanoparticles away from the colloidal solutions by centrifugation. Contrary to the previously made assumption in this field, it is found that Au nanoparticles do not contribute to RF energy absorption. The electrical conductivity measurement of the solutions with and without Au nanoparticles reveals that the Joule heating via ionic conduction in the electrolyte solutions is the dominant mechanism of RF-radiation-to-thermal conversion.
authors.affiliation: Department of Electrical and Computer Engineering, Petersen Institute of NanoScience and Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA.
authors.forename: Dongxiao
authors.initials: D
authors.lastname: Li
authors.forename: Yun Suk
authors.initials: YS
authors.lastname: Jung
authors.forename: Susheng
authors.initials: S
authors.lastname: Tan
authors.forename: Hong Koo
authors.initials: HK
authors.lastname: Kim
authors.forename: Eamon
authors.initials: E
authors.lastname: Chory
authors.forename: David A
authors.initials: DA
authors.lastname: Geller
mesh_terms: D004553:Electric Conductivity; D017979:Gold Colloid / Q000737:chemistry*; D006358:Hot Temperature; D007477:Ions / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry* / Q000528:radiation effects*; D011827:Radiation; D011846:Radio Waves
chemical_list: D017979:Gold Colloid; D007477:Ions