4-AMINO-TEMPO is widely used as a spin label in electron paramagnetic resonance (EPR) spectroscopy to study molecular dynamics and structural changes in biological systems. Its primary application lies in labeling proteins, nucleic acids, and membranes, allowing researchers to monitor conformational changes, folding, and interactions at the molecular level. Due to the stable nitroxide radical, it provides a sensitive probe for detecting local environmental changes such as pH, polarity, and viscosity.

It is also employed in polymer science as a mediator in controlled radical polymerization techniques, enabling precise tuning of molecular weight and architecture of polymers.

Additionally, 4-AMINO-TEMPO serves as a catalyst in selective oxidation reactions, particularly for the oxidation of alcohols to aldehydes or ketones in organic synthesis. It functions as a recyclable mediator in these processes, often in combination with co-oxidants, and its good water solubility makes it suitable for eco-friendly aqueous media.

Furthermore, it acts as an intermediate in synthesizing functionalized nitroxides for use in catalysis, sensors, and antioxidant studies. Its amino group allows for easy conjugation with biomolecules and surfaces, expanding its utility in bioconjugation and material science applications.