Nitracrine (dihydrochloride hydrate), a 1-nitroacridine derivative, inhibits RNA synthesis, reversibly binds to DNA, and forms covalent adducts with DNA in vivo. It is a potent hypoxia-selective and antitumor agent in vitro, exhibiting cytotoxicity towards most cells [1] [2] [3].

Nitracrine (2 μM; 1 h) causes 50% mortality in human erythroleukemia K562 cells when exposed to light for 48 minutes, while it requires 8.5 hours in darkness [3]. The LD50 values for nitracrine in P388, NIH3T3, and K562 cells are 0.23 μM, 0.6 μM, and 0.16 μM, respectively, after 1 hour of incubation under light [3]. Cell Viability Assay [3] Cell Line: Human erythroleukemia K562 cells Concentration: 2 μM Incubation Time: 1h Result: Achieved 50% cell death under 48 minutes of illumination.