PMAxx™ dye is a DNA modifier used for viability PCR, invented by scientists at Biotium. PMAxx™ is a new and improved version of our popular viability dye PMA (propidium monoazide).
PMAxx™ dye is a DNA modifier used for viability PCR, invented by scientists at Biotium. PMAxx™ is a new and improved version of our popular viability dye PMA (propidium monoazide). Like PMA, PMAxx™ is a photo-reactive dye that binds to dsDNA with high affinity. Upon photolysis with visible light, PMAxx™ dye becomes covalently attached to dsDNA. The PMAxx™-modified dsDNA cannot be amplified by PCR. PMAxx™ dye is designed to be cell membrane-impermeable. Thus, in a population of live and dead cells, only dead cells are susceptible to DNA modification due to compromised cell membranes. This unique feature makes PMAxx™ highly useful in selective detection of live bacteria by qPCR.
PMAxx™ was designed by Biotium scientists to be a superior alternative to PMA. While PMA is generally effective at differentiating between live and dead bacteria by qPCR, it does not completely eliminate PCR products from dead cell DNA. This could potentially give false positive results. Biotium’s new dye PMAxx™ is much more effective at eliminating PCR amplification of dead cell DNA, and therefore provides the best discrimination between live and dead bacteria.
Since Biotium first developed PMA dye, there have been numerous publications on the use of the dye in pathogenic bacterial detection related to food and water safety, medical diagnosis and biodefense (download the PMA Reference List). PMAxx™ should be compatible with all existing PMA protocols, but with superior activity. Of course we also still sell the classic PMA dye, in water (40019) or lyophilized format (40013).