Methyl 5-DOXYL-stearate is widely used in electron paramagnetic resonance (EPR) spectroscopy as a spin label. It helps in studying the dynamics and structure of lipid membranes by incorporating into lipid bilayers, providing insights into membrane fluidity and organization. The compound is also utilized in research to investigate the behavior of free radicals in biological systems, aiding in the understanding of oxidative stress and related processes. Additionally, it serves as a tool in material science for analyzing molecular interactions and mobility in complex systems.