Phenoxazines

Resazurin (7-Hydroxy-3H-phenoxazin-3-one 10-oxide) is a phenoxazine dye that is weakly fluorescent, nontoxic, cell-permeable, and redox‐sensitive. Resazurin has a blue to purple color above pH 6.5 and an orange color below pH 3.8. It is used in microbiological, cellular, and enzymatic assays because it can be irreversibly reduced to the pink-colored and highly fluorescent resorufin (7-Hydroxy-3H-phenoxazin-3-one). At circum-neutral pH, resorufin can be detected by visual observation of its pink color or by fluorimetry, with an excitation maximum at 530-570 nm and an emission maximum at 58

Phenoxazine is a heterocyclic compound. The structure of phenoxazine consists of an oxazine fused to two benzene rings. It occurs as the central core of a number of naturally occurring chemical compounds such as dactinomycin and litmus. The dyes Nile blue and Nile red are also based on a phenoxazine core.

chemical compound

Gallocyanin is a chemical compound classified as a phenoxazine dye. In combination with certain metals, it is used to prepare gallocyanin stains that are used in identifying nucleic acids.