title: Effect of microwave radiation on permeability of liposomes. Evidence against non-thermal leakage.
abstract: The effect of 2.45 GHz microwave radiation on the permeability of unilamellar phosphatidylcholine liposomes has been studied. Leakage of 5(6)-carboxyfluorescein from the liposomes was measured using spectrofluorimetry after exposure to either microwaves or thermal heating for 5-20 min intervals. The exposure temperature, 37.6 +/- 0.5 degrees C, was well above the phase transition temperature of the lipid membrane. The microwave exposure did not result in any non-thermal increase in permeability above that produced by thermal heating. This study refutes the results reported by Saalman et al. [1] in which an increased liposome permeability due to microwave exposure was reported. The refined analysis in the present study shows that this increased liposome permeability was not a non-thermal microwave effect.
authors.affiliation: Department of Microwave Technology, Chalmers University of Technology, Gothenburg, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Bergqvist
authors.forename: L
authors.initials: L
authors.lastname: Arvidsson
authors.forename: E
authors.initials: E
authors.lastname: Pettersson
authors.forename: S
authors.initials: S
authors.lastname: Galt
authors.forename: E
authors.initials: E
authors.lastname: Saalman
authors.forename: Y
authors.initials: Y
authors.lastname: Hamnerius
authors.forename: B
authors.initials: B
authors.lastname: Nordén
mesh_terms: D005452:Fluoresceins; D006358:Hot Temperature; D008081:Liposomes / Q000737:chemistry / Q000528:radiation effects*; D008872:Microwaves; D010539:Permeability; D012449:Safety
chemical_list: D005452:Fluoresceins; D008081:Liposomes; C024098:6-carboxyfluorescein