01/03/2014
Dosimetric Assessment of Two-Layer Cell Culture Configurations for Fertility Research at 1950 MHz
Yijian Gong, Manuel Murbach, Teruo Onishi, Myles Capstick, Toshio Nojima, and Niels KusterE, IEICE Transactions on Communications, Volume E97-B, Issue 3, pp. 631-637, online March 1, 2014
In this paper, we investigate the methods for assessing the impact of electromagnetic (EM) radiation on cells cultured for fertility research in monolayer and in suspension. The techniques used to culture spermatozoa in two layers, composed of culture medium and mineral oil, require adjustment of the dosimetric assessment routine. Exposure conditions in 35 mm Petri dishes were analyzed for three suspension-culturing configurations – medium only and two oil/medium multilayer configurations – and one oil/medium multilayer monolayer configuration. Detailed numerical and experimental dosimetry assessments were performed for the configurations exposed to the standing wave of R18 waveguides operated at 1950 MHz. The numerical dosimetry was verified by dosimetric temperature measurements. The non-uniformity of the specific absorption rate (SAR) distribution is 30% for monolayers, and 59 – 75% for suspension configurations.
The scientific and technical impact of this study can be summarized as:
- We addressed the special requirements for investigation of EM exposure of cells grown in the multilayer medium/oil cultures used in fertility research. Because the dielectric properties and thermal parameters of the oil differ from those of the culture medium, exposure in multi-layer configurations is significantly altered compared to media-only cultures.
- Detail numerical and experimental dosimetry assessments were performed for different configurations. The exposure system allows SAR levels up to 6W/kg/W for the suspension cells and 40 W/kg/W for monolayer cells to be measured.
- The largest temperature increase measured, in the suspension configurations, is less than 0.08°C/W/kg.
- The non-uniformity of the exposure for suspension configurations is relatively large, greater for medium only than for oil/medium multilayer. The implications of this non-uniformity for the outcomes of biological experiments need to be comprehensively addressed.