Assessing solvated electron uptake in low-temperature plasma-exposed solutions as a pathway to quantifying plasma...

Area of Science:

• Plasma Physics
• Chemical Kinetics
• Radiation Chemistry

Background:

• Low-temperature plasma (LTP) is an emerging radiation source with unique chemical properties.
• Reactive plasma species, particularly electrons, play a key role in plasma-induced chemical reactions.
• Accurate quantification of plasma-derived species is essential for understanding LTP applications, especially in biological systems.

Purpose of the Study:

• To quantify the uptake of solvated electrons transferred from low-temperature plasma (LTP) into aqueous solutions.
• To investigate the influence of different plasma conditions, other plasma species, and solution pH on electron uptake rates.

Main Methods:

• A fluorometric detection method was utilized, based on the two-electron reduction of nitrate to nitrite ions.
• Solvated electron uptake was measured under two distinct low-temperature plasma conditions.
• The impact of solution pH and co-existing plasma species on uptake kinetics was explored.

Main Results:

• The estimated uptake of solvated electrons was consistently below 0.1 mM under the tested conditions.
• This low concentration suggests a minimum transfer of plasma electrons to the solution.
• Solution pH and the presence of other plasma species were found to influence uptake rates.

Conclusions:

• The study establishes a method for quantifying solvated electron uptake from LTP, yielding low mM concentrations.
• Accurate measurement of electron transfer is critical for assessing the safety and efficacy of LTP in biological applications.
• Further research is needed to fully elucidate the mechanisms governing electron transfer and its impact on biomolecules.