How Far Does Cold Plasma Reach in Tissues? A Study With Biocompatible Hydrogels

ABSTRACT This study presents a novel protocol to quantify the surface distribution, penetration depth and concentration of reactive oxygen and nitrogen species (RONS) generated by plasma in biocompatible hydrogels, serving as tissue surrogates. Using colorimetric probes, we visualized and quantified RONS interaction through color intensity analysis. Two types of hydrogels were used—agarose and gelatin—at different concentrations, to study how composition and concentration affect the interaction of plasma‐generated RONS. The results show that the surface distribution and penetration depth of RONS increase with treatment time and depend on the chemical structure and concentration of the hydrogel. This methodology offers a reproducible, animal‐free approach to optimize plasma‐based therapies by enabling precise assessment of ROS and RNS behavior in 3D tissue‐like environments.