Using an Inclined Waveguide Cavity to Improve the Resonant Exposure on Cultured Cells

For the 1800-MHz waveguide cavity applied to resonant exposure on the cell monolayer, a novel method was proposed to improve the dosimetry by inclining the waveguide from the current H
_max
/H
_p
case and H
_max
/E
_p
case. A shorted WR-430 waveguide was fabricated and specialized to incline around the longitudinal axis. The 35-mm-diameter Petri dishes, each filled with 3.1-mL culture medium, were placed at the H-field maximum in the waveguide. The numerical calculation, with the finite-difference time-domain method, was comparatively validated by theoretical solution and experimental measurement. Based on the calculated specific absorption rate in the cell monolayer, the exposure efficiency, exposure inhomogeneity, and temperature rise were evaluated. For the double-dish and quadruple-dish exposures, the optimum angle of the waveguide inclination is 8° from the H
_max
/H
_p
case. The inclined exposure increases the exposure efficiency by a factor of 3.2-4.7 and decreases the exposure inhomogeneity by 44%-46%. The temperature rise was provided for each exposure scenario. The study proved the significant efficiency increase and inhomogeneity decrease of the proposed method. The method can be introduced to a variety of setups presently used in experiments with resonant exposure on cultured cells.