Methylene Violet 3RAX, a phenazine dye, is utilized for staining cell mitochondria and has the capability to alter DNA's molecular structure, disrupt DNA modules, and promote reactive singlet oxygen generation. It inhibits human erythrocyte AChE and human plasma BChE, with Ki values of 1.58 and 0.51 μM, respectively, highlighting its potential as a photosensitizer for mitochondrial targeting in photodynamic therapy (PDT) [1] [2].