Setup for simultaneous microwave heating and real-time spectrofluorometric measurements in biological systems

Abstract

In this paper, a delivery system allowing simultaneous microwave heating and real-time spectrofluorometric measurements in biological systems is proposed and characterized. This system is used to investigate the phase behavior of lipid bilayers from about 15ffiC to 45ffiC. The delivery system is based on an open transverse electromagnetic (TEM) cell combined with a spectrofluorometer via an optical cable system. A numerical and experimental dosimetry of the delivery system is conducted. The Specific Absorption Rate (SAR) efficiency of the system is 26:1ffi2:1 W/kg/W. Spectrofluorometric measurements on Laurdan labeled small unilamellar vesicles (SUVs) are carried out. Generalized polarization (GP) of the SUV's membrane is obtained from the fluorescence intensities measured at two emission wavelengths.