Effects of the addition of sodium chloride to a tetrameric protein in water solution during exposure to high frequency electromagnetic field

Abstract

Background: Previous studies have shown that exposure to high frequency electromagnetic fields induces alterations in simple organic systems such as proteins in bidistilled water solution. Objective: The aim of this study was to test the shielding action of sodium chloride in bidistilled water solution against exposure to a high frequency electromagnetic field, in order to evaluate if the addition of NaCl in proteins aqueous solution can be considered a valuable bioprotector against electromagnetic fields. Method: Samples of 250 μl of different hemoglobin aqueous solutions, in the absence or presence of sodium-chloride, were exposed for 3 hours to an electromagnetic field at 1750 MHz at a power density around 1 W/m 2 emitted by an operational mobile phone. Fourier Transform Infrared Spectroscopy was used to study the effects of exposure on the secondary structure of hemoglobin also in the presence of sodium-chloride. Results: Spectral analysis evidenced that significant increase in intensity of the Amide I and II vibration bands in hemoglobin bidistilled water solution occurred after exposure to the electromagnetic field. This result can be due to the increase of dipole moment of the protein due to the alignment of α-helix towards the direction of the field. In contrast, no appreciable change was observed in hemoglobin in sodium-chloride water solution after exposure. This protective effect of sodium-chloride can be explained by the orientation of water molecules due to the strong electric field around each ion that reduces the possibility of rotation of the protein in response to an applied electromagnetic field.