Effects of 2.45-GHz microwave and 100-MHz radiofrequency radiation on liposome permeability at the phase transition temperature.
Large unilamellar dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG) liposomes loaded with an aqueous chemotherapeutic drug, cytosine arabinofuranoside (ARA-C), were exposed for 30 min to 60 W/kg continuous-wave (CW) 100-MHz or 2.45-GHz radiation in vitro at temperatures between 37 degrees C and 43 degrees C. Liposomes were exposed in HEPES buffer or in HEPES buffer supplemented with 44% by volume fetal calf serum (FCS). Characteristic phase transition responses were detected in the range of 39 degrees C to 40 degrees C with the presence of FCS, increasing maximum % release of 3H-ARA-C by 20% relative to HEPES suspension. Neither frequency of electromagnetic radiation had any detectable effect on liposome permeability or the location of the phase transition in the presence or absence of FCS.
Liu
L M
LM
Department of Physiology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298.
Cleary
S F
SF
D003561:Cytarabine / Q000008:administration & dosage; D004337:Drug Carriers; D066298:In Vitro Techniques; D008081:Liposomes / Q000528:radiation effects*; D008872:Microwaves; D010539:Permeability; D011846:Radio Waves; D013816:Thermodynamics
D004337:Drug Carriers; D008081:Liposomes; D003561:Cytarabine