Related Experiment Video
Updated: Jun 6, 2026

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Deprotonation of glutamic acid induced by weak magnetic field: an FTIR-ATR study
A De Ninno1, A Congiu Castellano
1C.R. ENEA Frascati Department UTAPRAD-DIM, via E. Fermi 27, 00044 Frascati, Italy. antonella.deninno@enea.it
Abstract:
It has been claimed that weak extremely low frequency electromagnetic fields (ELF-EMFs) can affect biochemical reactions and a wide-ranging body of literature is available on this topic. Nevertheless, the physical nature of these effects remains largely unknown. We investigated the influence of ELF-EMF on glutamic acid solutions using Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectra. Samples were exposed for 10, 20, or 30 min to a weak EMF generated by Helmoltz coils, and then placed in a spectrometer. After exposure, those solutions that had a pH lower than the isoelectric point tended to show a shift toward the deprotonation of the carboxylic group, while solutions having a pH greater than the isoelectric point showed the deprotonation of the residual amine group. Moreover, at low pH values, we also detected a shift of the δ(antisym) band of the amine. The effects lasted a few minutes after exposure before the native configuration was restored. The spectral modifications were observed after each independent exposure to EMFs, and the same effects were seen by varying the frequencies in the range of 0-7 kHz. Therefore, the hypothesis of the existence of a resonant frequency that has been proposed elsewhere cannot be supported by the results of this study. The most surprising characteristic of this effect is the long-lasting nature of the perturbation, which is hard to be explained in terms of short-living excitations in biological matter.
More Related Videos
07:08Fast Micro-iontophoresis of Glutamate and GABA: A Useful Tool to Investigate Synaptic Integration
Published on: July 31, 2013
13:56The Use of Magnetic Resonance Spectroscopy as a Tool for the Measurement of Bi-hemispheric Transcranial Electric Stimulation Effects on Primary Motor Cortex Metabolism
Published on: November 19, 2014
Related Concept Videos
π Electron Effects on Chemical Shift: Overview
Proton (¹H) NMR: Chemical Shift
Absorption signals of all the protium nuclei in a...
¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
NMR Spectroscopy Of Amines
NMR and Mass Spectroscopy of Carboxylic Acids
While α protons of carboxylic acids absorb at 2–2.5 ppm, β protons absorb further upfield.
Carboxylic acids are easily identified by dissolving them in deuterium oxide, which results in a rapid exchange of the acidic protons with deuterium. This leads to the disappearance of the acidic...
¹H NMR of Labile Protons: Temporal Resolution
The –OH proton in alcohols typically appears in the range of δ 2 to 5 ppm but can vary depending on the specific...