Differentiation between the Various Species of Free Radicals Appearing in Irradiated Keratin

Abstract

The various species of free radicals formed on irradiation of wool keratin are compared as a function of power during EPR measurements, and as a function of the shape of the EPR signals during decay. It is shown that the change of size of the signal as a function of power is different for some different species of radicals, even though they may usually appear under common envelopes. Thus a method is available to study separately the behavior of the various species of radicals in wool having a common EPR envelope. Inspection of spectra of irradiated wool during decay in the dark reveals that one species of glycine-type radical diminishes, while another species of glycine-tye radical increases. This suggests that the kinetics of various radical species in wool are interdependent.

Keywords

Wool fiber light irradiation free radicals EPR spectrum power saturation glycine-type signal cystine-type signal different radical species lower settings light intensity signal increase sulfur radicals kinetics interchange signal decay illumination time decay time interdependence interdependent species second order kinetics mixed terms.

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