Effects of Extremely Low Frequency Magnetic Field on the Secondary Structures of β-Amyloid and Human Serum Albumin

Human serum albumin and β-amyloid were exposed to extremely low frequency (ELF) magnetic field of 1.5 mT intensity and 50 Hz frequency. The effects of exposure were investigated in the mid-infrared region by means of Fourier selfdeconvolution spectroscopic analysis. The experimental results suggest that exposure to the ELF magnetic field has reversible effects on the out of phase combination of N–H in plane bending and C–N stretching vibrations of the secondary structures of the two proteins. The exposure of β-amyloid and human serum albumin to ELF magnetic field affected the absorption spectra of the vibration bands by changes in peak positions for the amide II bands and changes of intensities in most of the bands in the amide I and amide II regions. In the fingerprint region, the most sensitive vibrations to the magnetic field are found to be in the (720-600) cm-I range. After removing the magnetic field, it took the vibration bands more than 10 minutes of a gradual change toward returning to their original spectra, obtained before the exposure. It is suggested that hydrogen bonds can alter the frequency of a stretching vibration depending on the increase or decrease of strain on the vibrations.This work is supported by the German Research Foundation DFG Grant No. DR228/24-2