Towards predicting intracellular radiofrequency radiation effects

Abstract

Recent experiments have reported an effect of weak radiofrequency magnetic fields in the MHz-range on the concentrations of reactive oxygen species (ROS) in living cells. Since the energy that could possibly be deposited by the radiation is orders of magnitude smaller than the energy of molecular thermal motion, it was suggested that the effect was caused by the interaction of RF magnetic fields with transient radical pairs within the cells, affecting the ROS formation rates through the radical pair mechanism. It is, however, at present not entirely clear how to predict RF magnetic field effects at certain field frequency and intensity in nanoscale biomolecular systems. We suggest a possible recipe for interpreting the radiofrequency effects in cells by presenting a general workflow for calculation of the reactive perturbations inside a cell as a function of RF magnetic field strength and frequency. To justify the workflow, we discuss the effects of radiofrequency magnetic fields on generic spin systems to particularly illustrate how the reactive radicals could be affected by specific parameters of the experiment. We finally argue that the suggested workflow can be used to predict effects of radiofrequency magnetic fields on radical pairs in biological cells, which is specially important for wireless recharging technologies where one has to know of any harmful effects that exposure to such radiation might cause.

Molecular Oxygen Binding in the Mitochondrial Electron Transfer Flavoprotein

“…In particular, the approach could be used in a subsequent study to chart the dynamics and binding of superoxide, once produced through oxidation by FADH 4 A ROS branching point exists where the reaction has two separate pathways, which -under specific magnetic field conditionscan be controlled by singlet-triplet interconversion. [59][60][61] At the most fundamental level, one should investigate how such a radical pair reaction can be controlled by perturbing spin interconversion through applied optimal magnetic fields to control the outcome of ROS production in the ETF enzyme. Crucially, this will lead to predictive power of the computational model, which could, possibly along with in silico mutational analysis (e.g.…”

“…In this general reaction scheme, an electron is transferred from reduced flavin to triplet O 2 , which results in O 2 •– and a flavosemiquinone (FADH • ) spin-correlated caged radical pair . A ROS branching point exists where the reaction has two separate pathways, whichunder specific magnetic field conditionscan be controlled by singlet–triplet interconversion. − At the most fundamental level, one should investigate how such a radical pair reaction can be controlled by perturbing spin interconversion through applied optimal magnetic fields to control the outcome of ROS production in the ETF enzyme. Crucially, this will lead to predictive power of the computational model, which could, possibly along with in silico mutational analysis (e.g., β-D128N and β-R191C known to influence ROS production), allow for experimental validation of the approach.…”

MolSpin—Flexible and extensible general spin dynamics software

“…4, such that the quantum yields depend on the amplitude, frequency, phase, and polarization of the oscillating magnetic field. In some very special cases of oscillating magnetic fields, the time-dependence of the spin system Hamiltonian can be removed by transforming it to a rotating reference frame, 9,42 but normally one would have to deal with a timedependent Hamiltonian when working with oscillating magnetic fields, and in such cases, Eqs. (1) and (4) can be solved by numerical integration.…”

“…involved in simulating realistic spin systems, 9 MolSpin still has the ability to simulate even the most complex spin dynamics, and in fact, the name MolSpin-molecular spin dynamics-originates from a desire to perform realistic spin dynamics simulations by directly including the thermal fluctuations in interaction parameters that may be obtained from MD simulations.…”

“…[5][6][7][8] Radical pairs have also been proposed to influence formation of reactive oxygen species inside biological cells when exposed to radiofrequency radiation. [9][10][11][12] All of the aforementioned radical pair processes rely on the interaction of the spin of unpaired electrons with magnetic fields applied externally and created internally by the atomic constituents of the radicals involved. Magnetic field effects are, however, not limited to radical pairs as it has been shown how the presence of a third radical might drastically affect the spin dynamics of a multiradical system, 13,14 and the use of nitrogen-vacancy centers in nanodiamonds as magnetic sensors demonstrates how spin interactions with external magnetic fields can play a role even without any radicals present.…”