PMA dye



Product Description

PMA™ (propidium monoazide) is a high affinity photoreactive DNA binding dye invented by scientists at Biotium. The dye is weakly fluorescent by itself but becomes more fluorescent after binding to nucleic acids. It preferentially binds to dsDNA with high affinity. Upon photolysis, the photoreactive azido group on the dye is converted to a highly reactive nitrene radical, which readily reacts with any hydrocarbon moiety at the binding site to form a stable covalent nitrogen-carbon bond, thus resulting in permanent DNA modification. The dye is nearly completely 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 makes the dye highly useful in the 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. 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. Please also see PMA dye in H2O (40019), a convenient ready-to-use format. For viability PCR of gram-negative bacteria we highly recommend using our new PMA Enhancer (31038) in conjunction with PMA. PMA Enhancer for Gram Negative Bacteria was designed to improve PMA-mediated discrimination between live and dead gram-negative bacteria. When a sequence from a gram-negative bacteria is amplified by PCR, samples pre-treated with Enhancer show a decrease in the signal from dead cells, with no change in the signal from live cells. Biotium also provides strain-specific PMA Real-Time PCR Bacterial Viability kits with validated primers for 7 selected pathogens: M. tuberculosis, S. aureus, MRSA, Salmonella, E. coli, E. coli O157:H7 and Listeria. These kits provide everything that you need for the selective detection of your favorite species of live bacteria by real-time PCR.

PMA diagram
Principal of selective detection of live cells using PMA dye.
  • Molecular weight: 511
  • Abs = 464 nm (before photolysis)
  • Abs/Em = 510/610 nm (following photolysis and covalent attachment to DNA/RNA)
  • Dark red solid soluble in DMSO or DMF
  • Store at 4°C and protect from light at all times

Nocker, A., Cheung, C.Y., and Kamper, A.K. (2006). Comparison of propidium monoazide with ethidium monoazide for differentiation of live vs. dead bacteria by selective removal of DNA from dead cells. J. Microbio Meth. 67(2), 310-320.

Download the full PMA Reference List.

Flyer (PDF): FL-PMA-and-PMAxx-2015
MSDS (PDF): MSDS 40013_030712
Protocol (PDF): PI-40013, 40019

Reference List (PDF): PMA-References

Shipment Method: Shipping and handling methods will be assessed and calculated at time of shipment based upon item(s) storage temperature conditions.

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Please note that products will be shipped at ambient temperature. This will not affect performance if the products are kept at the indicated temperature for long term storage. Please refer to the package insert for correct storage conditions.

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