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Updated: May 23, 2026

Synthesis of Plant Phenol-derived Polymeric Dyes for Direct or Mordant-based Hair Dyeing
Published on: December 1, 2016
[Effect of ascorbic acid (vitamin C) on the EPR spectra from the black and red hair]
E Chikvaidze1, A Miminoshvili, T Gogoladze
1I. Javakhishvili Tbilisi State University, Georgia.
Abstract:
The EPR spectra of melanin's free radicals in natural black and red hair have been investigated. It is show that the EPR spectrum of black hair is slightly asymmetric singlet with g=2,0035 and ΔH=0,5 mTl. The EPR spectrum of red hair with g=2,0053 differs from the spectrum of black hair. Under the influence of visible (blue with λ(max)=450 nm) in both types of hair (black and red), the protoinduced free radicals appear, which indicates an increase in the intensity of already existing EPR spectrum of hair. It should be noted that the EPR spectra of red hair from various donors are different. The antioxidant ascorbic acid has the different effect on the photoinduced free radicals. In particular, in the case of black hair, the concentration of photoinduced free radicals is slightly reduced, whereas in red hair, the disappearance of the triplet in the spectrum is observed, and at the same time, the spectrum becomes a singlet, the intensity of which increases sharply.
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