Induced movements of giant vesicles by millimeter wave radiation.
Our previous study of interaction between low intensity radiation at 53.37GHz and cell-size system - such as giant vesicles - indicated that a vectorial movement of vesicles was induced. This effect among others, i.e. elongation, induced diffusion of fluorescent dye di-8-ANEPPS, and increased attractions between vesicles was attributed to the action of the field on charged and dipolar residues located at the membrane-water interface. In an attempt to improve the understanding on how millimeter wave radiation (MMW) can induce this movement we report here a real time evaluation of changes induced on the movement of giant vesicles. Direct optical observations of vesicles subjected to irradiation enabled the monitoring in real time of the response of vesicles. Changes of the direction of vesicle movement are demonstrated, which occur only during irradiation with a "switch on" of the effect. This MMW-induced effect was observed at a larger extent on giant vesicles prepared with negatively charged phospholipids. The monitoring of induced-by-irradiation temperature variation and numerical dosimetry indicate that the observed effects in vesicle movement cannot be attributed to local heating.
IFT-CNR, 00133 Rome, Italy.
Martina
M
Albini
ISM-CNR, 00133 Rome, Italy.
Simone
S
Dinarelli
Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Turin, Italy.
Francesco
F
Pennella
IREA-CNR, 89124 Naples, Italy.
Stefania
S
Romeo
IMM-CNR, 00133 Rome, Italy.
Emiliano
E
Zampetti
ISM-CNR, 00133 Rome, Italy.
Marco
M
Girasole
Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Turin, Italy.
Umberto
U
Morbiducci
Department of Physics, University Federico II, 89126 Naples, Italy.
Rita
R
Massa
IFT-CNR, 00133 Rome, Italy. Electronic address: alfonsina.ramundoorlando@ift.cnr.it.
Alfonsina
A
Ramundo-Orlando
D048429:Cell Size / Q000528:radiation effects; D004058:Diffusion; D008872:Microwaves; D022161:Transport Vesicles / Q000378:metabolism* / Q000528:radiation effects*; D014867:Water / Q000378:metabolism
D014867:Water
Giant vesicles; Millimeter waves; Movement changes; Non thermal mechanism; Real-time exposure; Vesicles trajectories