DHX-SP is a fluorescent probe utilized to visualize superoxide anion (O2·–) and peroxynitrite (ONOO–) during ferroptosis in PC12 cells and in Parkinson's disease models.

DHX-SP, when pre-incubated with superoxide anion (O2 ·–), emits red fluorescence with a peak excitation wavelength of 560 nm and a peak emission wavelength of 710 nm. In contrast, when pre-incubated with both superoxide anion (O2 ·–) and peroxynitrite (ONOO–), it exhibits green fluorescence, with a peak excitation wavelength of 470 nm and a peak emission wavelength of 560 nm.