Acetylcysteine-15N is a version of Acetylcysteine labeled with nitrogen-15 (\[^15N\]). Acetylcysteine (N-Acetylcysteine) functions as a mucolytic agent, effectively reducing mucus viscosity. As a reactive oxygen species (ROS) inhibitor, it serves as a cysteine precursor and prevents heme-induced ferroptosis by neutralizing toxic lipids produced via arachidonic acid-dependent 5-lipoxygenase activity. Additionally, Acetylcysteine can induce apoptosis and exhibits antiviral activity against influenza. It represents the most stable form of cysteine for drug delivery and is utilized in studies of disulfidptosis.