PMA (propidium monoazide) is a high affinity photoreactive DNA binding dye invented by scientists at Biotium for viability PCR of bacteria and other organisms. It preferentially binds to dsDNA with high affinity. Upon photolysis, the dye covalently reacts with DNA, thus resulting in permanent DNA modification. The dye is cell membrane-impermeable, and thus can be selectively used to modify only exposed DNA from dead cells while leaving DNA from viable cells intact. This feature allows selective detection of viable pathogenic cells by quantitative real-time PCR in the presence dead cells whose DNA has been PMA-modified and thus can not be amplified. PMA has been used extensively in bacterial detection related to food and water safety, medical diagnosis and biodefense. 1 mg Molecular weight: 511 Abs = 464 nm (before photolysis) Abs/Em = 510/610 nm (following reaction with DNA/RNA) Dark red solid soluble in DMSO or DMF Store at 4C and protect from light at all times
