Real-time In Situ Electron Spin Resonance Measurements on Fungal Spores of Penicillium digitatum during Exposure of Oxygen Plasmas

TL;DR

This study uses real-time in situ electron spin resonance to analyze free radicals on fungal spores exposed to oxygen plasma, revealing radical behavior linked to spore inactivation.

Contribution

First application of real-time in situ ESR to monitor plasma-induced radical reactions on fungal spores during oxygen plasma exposure.

Findings

ESR signals observed from fungal spores, assigned to semiquinone radicals

Signal decay correlates with fungal spore inactivation

ESR effectively elucidates plasma-surface biological interactions

Abstract

We report the kinetic analysis of free radicals on fungal spores of Penicillium digitatum interacted with atomic oxygen generated plasma electric discharge using real time in situ electron spin resonance (ESR) measurements. We have obtained information that the ESR signal from the spores was observed and preliminarily assignable to semiquinone radical with a g-value of around 2.004 and a line width of approximately 5G. The decay of the signal is possibly linked to the inactivation of the fungal spore. The real-time in situ ESR has proven to be a useful method to elucidate plasma-induced surface reactions on biological specimens.