EPR study of gamma induced radicals in amino and iminodiacetic acid derivatives

Abstract

In this study, electron paramagnetic resonance spectroscopy was used to investigate free radicals formed in gamma irradiated L-glutamine hydrochloride, iminodiacetic acid hydrochloride and N-(2-hyroxyethyl) iminodiacetic acid powders. The free radicals produced in L-glutamine hydrochloride powders were attributed to the CH 2Ċ HCOOH radical; and those in iminodiacetic acid hydrochloride and N-(2-hyroxyethyl) iminodiacetic acid powders to the HNCHCH 2 (COOH) 2 and HOCH 2 CH 2 NĊHCH 2 (COOH) 2 , respectively. The g-values of the radicals and the hyperfine structure constants of the free electron with the environmental protons and 14 N nucleus were determined. The samples were not displayed before they were not irradiated. The free radicals were found stable at room temperature for more than six months. Some spectroscopic properties and suggestions concerning possible structure of the radicals are discussed in this paper.

EPR and FT-IR spectroscopic studies of l-lysine monohydrochloride and l-glutamic acid hydrochloride powders

“…The radiation damage centers of these samples have been attributed to the HOOCCH 2 CH 2 Ċ HCOOH radical and the reported values of the hyperfine constants a LGAHCl. Moreover, the g value of the radical discussed here seems to be in agreement with the literature data for their analogs and various other alkyl type radicals [28][29][30].…”

Electron paramagnetic resonance study of free radicals in γ-irradiated L-glutamine and L-glutamine-t-butyl ester hydrochloride

“…When the magnetic field is along the a axis, the NCH 2Ċ H radical indicates only that the unpaired electron is interacted with nitrogen nucleus. The hyperfine coupling constant for the 14 The characterization of the radical is found by comparing the simulated and experimental spectra, and by addition of the derived hyperfine splittings with those obtained in similar radicals (17,19,20). The experimental and simulated EPR spectra were found to be in agreement well with each other, as shown in Figure 1(a) and 1(b).…”

“…Radiation damage center was attributed to theĊH andṄH 2 . Besides, the free radical produced in l-glutamine hydrochloride powders was attributed to the CH 2Ċ HCOOH (17). The single crystals of Nα-acetyl-l-glutamine were indicated by the formation of two types of radicals as a result of γ -irradiation at room temperature (9).…”

The effect of gamma radiation of amino acid derivatives in the solid state: an EPR study

“…The hyperfine constants and g value of the radical discussed here seem to agree well with the literature values of their analogous (27) and amine radicals. (30,31) Glycine is the simplest amino acid, and research shows it to be physiologically active and important to cell metabolism. DMG supplies methyl groups for modification, building and detoxifying many constituents in the body and acts as an antioxidant.…”