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This paper studies the effects of electromagnetic fields (EMF), specifically with circular electric field polarization, on the structure of Hemoglobin. Nearly all of the previous studies are based on linearly-polarized waves. But our comparative study based on a novel dual-polarized waveguide exposure device, shows that the EMF effects on macromolecules such as hemoglobin are polarization-dependent, and that circularly-polarized EMFs with the same incident power density can have significantly stronger effects on the structure of Hemoglobin. A novel dual-polarized exposure device is employed, followed by intrinsic fluorescence spectroscopy, UV–Vis spectroscopy, and far UV Circular Dichroism Spectroscopy, to show that the helical content is significantly reduced under circular as compared to linear polarization. This corresponds to a certain unwinding effect through the circularly-polarized EMF. The physical basis for the observed results is discussed together with implications for further research.
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... In modern life, electromagnetic fields are widely employed, influencing living organisms. The functionality of protein systems (including enzymatic ones) can be altered under the action of magnetic [2] and electromagnetic fields [3][4][5][6][7][8][9][10]. In this way, in previous studies, we demonstrated that electric fields, triboelectrically induced by liquid flow through polymeric pipes of thermal stabilization coils, influence the adsorbability of the horseradish peroxidase (HRP) enzyme protein onto mica substrates [5][6][7]. ...
... Lopes et al. [9] found that 2450 MHz [11] microwave radiation can cause a significant (up to >80%) loss in the HRP enzymatic activity after a 0.5 h treatment at 60 • C and 60 W microwave power. Hamedi et al. demonstrated partial unfolding of adult hemoglobin (HbA) after exposure to a 940 MHz circularly polarized electromagnetic field [8]. As regards HRP, a 52 mT static magnetic field was also shown to impact its enzymatic activity and optimum pH by inducing changes in its structure [2]. ...
... Namely, background electromagnetic radiation is concentrated upon its reflection from the interior surface of the half-sphere, leading to a change in the spatial topology of this radiation. Electromagnetic fields are known to influence proteins [1,[3][4][5][6][7][8][9][10]. Previously, we demonstrated that even ultra-weak electromagnetic fields, whose intensity is comparable to that of the background (of 10 −12 W/cm 2 power density) electromagnetic fields of a non-standard specific topology-such as knotted electromag-netic fields-can induce substantial alterations in protein adsorption properties [4]. ...
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... Electric [26][27][28][29][30][31], magnetic [32][33][34][35][36] and electromagnetic [37][38][39][40][41][42][43][44][45][46][47] fields are known to affect enzymes. In many papers, the effects of pulsed electric [26][27][28][29][30][31] and electromagnetic [42] fields on enzymes are considered. ...
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Book
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Currently, the biological effects of nonionizing electromagnetic fields (EMFs) including radiofrequency (RF) radiation have been the subject of numerous experimental and theoretical studies. The aim of this study is to evaluate the possible biological effects of mobile phone RF (940MHz, 15V/m and SAR=40mW/kg) on the structure of calf thymus DNA (ct DNA) immediately after exposure and 2h after 45min exposure via diverse range of spectroscopic instruments. The UV-vis and circular dichroism (CD) experiments depict that mobile phone EMFs can remarkably cause disturbance on ct DNA structure. In addition, the DNA samples, immediately after exposure and 2h after 45min exposure, are relatively thermally unstable compared to the DNA solution, which was placed in a small shielded box (unexposed ct DNA). Furthermore, the exposed DNA samples (the DNA samples that were exposed to 940MHz EMF) have more fluorescence emission when compared with the unexposed DNA, which may have occurred attributable to expansion of the exposed DNA structure. The results of dynamic light scattering (DLS) and zeta potential experiments demonstrate that RF-EMFs lead to increment in the surface charge and size of DNA. The structure of DNA immediately after exposure is not significantly different from the DNA sample 2h after 45min exposure. In other words, the EMF-induced conformational changes are irreversible. Collectively, our results reveal that 940MHz can alter the structure of DNA. The displacement of electrons in DNA by EMFs may lead to conformational changes of DNA and DNA disaggregation. Results from this study could have an important implication on the health effects of RF-EMFs exposure. In addition, this finding could proffer a novel strategy for the development of next generation of mobile phone.