Deuterium Magnetic Resonance Imaging Tracking of Deuterium Gas Releasing from Microneedle Patches for Wound Healing as a Stable Isotope Analogue of Hydrogen Gas Therapy

Abstract Hydrogen gas therapy has attracted considerable attention for the treatment of oxidative stress-related diseases owing to its excellent biosafety, selective antioxidant activity, and anti-inflammatory effects. However, its small molecular size, rapid diffusion, and short tissue retention time make in vivo tracking extremely challenging. Molecular deuterium (D2) is a stable isotopic form of hydrogen and has physicochemical properties similar to those of H2. Its deuterated products can be detected by deuterium magnetic resonance imaging (DMRI). In this study, we established a deuterium gas therapy and systematically compared the physicochemical properties and therapeutic effects of D2 and H2 through in vitro and in vivo experiments. Using 11.7 T DMRI, we visualized the dynamic behavior of deuterated products at the wound site. The imaging results revealed their local retention, penetration into deeper tissues, and gradual clearance over time. This approach provides a valuable platform for investigating the in vivo dynamics and therapeutic mechanisms of hydrogen gas therapy and may facilitate the development of precision gas therapeutics.