Changes in Liposomes Permeability Induced by Gramicidin D After Microwave Irradiation

The response of model membranes (Iiposomes) to microwave irradiation (9.2 GHz, energy absorption 20 mW/g, continuous 1.5-h exposure in an orthogonal waveguide) was determined spectrophotometrically by recording after irradiation the gramicidin D-induced cation permeability. The irridiation modified the gramicidin D-induced permeability to the cations K/sup +/, Na/sup +/, and Rb/sup +/ through the liposomes and seemed to facilitate the movement of Na/sup +/ and Rb/sup +/. These results are discussed in relation with the hypothesis that microwave radiation may induce changes to the structure of Iiposomes.