Talk:Propidium iodide

Disorganized Article

This article was disorganized and contained many pieces of information that did not contribute to a quick and general understanding of what PI is and its applications. Some of the text I removed may be re-added at a later date but did not seem general enough for an introductory section. Additionally, as other users have pointed out, a significant portion of the material was plagiarized directly from vendors' websites, including ThermoFisher. For readers who want more technical information on PI, I have included references back to these vendor sites but eliminated the parroted text. Gtpase (talk) —Preceding undated comment added 13:51, 7 March 2017 (UTC)

Copy and paste?

This phrase "The counterstaining protocols below are compatible with a wide range of cytological labeling techniques" appears exactly on the following page where it is indeed followed by descriptions of some protocols. Since there are no protocol descriptions following that paragraph in this article I suspect the text has been lifted from that other source.

http://www.mpbio.com/detailed_info.php?family_key=02195458  — Preceding unsigned comment added by 142.150.147.120 (talk) 13:27, 10 August 2011 (UTC) 

In addition, a significant portion of the earlier text was lifted from Invitrogen's corporate insert for PI.

"Propidium iodide (PI) binds to DNA by intercalating between the bases with little or no sequence preference and with a stoichiometry of one dye per 4–5 base pairs of DNA.1 PI also binds to RNA, necessitating treatment with nucleases to distinguish between RNA and DNA staining. Once the dye is bound to nucleic acids, its fluorescence is enhanced 20- to 30-fold, the fluorescence excitation maximum is shifted ~30–40 nm to the red and the fluorescence emission maximum is shifted ~15 nm to the blue.2 Although its molar absorptivity (extinction coefficient) is relatively low, PI exhibits a sufficiently large Stokes shift to allowsimultaneous detection of nuclear DNA and fluorescein-labeled antibodies, provided the proper optical filters are used. PI is suitable for fluorescence microscopy, confocal laser scanning microscopy, flow cytometry, and fluorometry.

PI is membrane impermeant and generally excluded from viable cells. PI is commonly used for identifying dead cells in a population and as a counterstain in multicolor fluorescent techniques. The counterstaining protocols below are compatible with a wide range of cytological labeling techniques—direct or indirect antibody-based detection methods, mRNA in situ hybridization, or staining with fluorescent reagents specific for cellular structures. These protocols can be modified for tissue staining."

This should probably either be referenced back to Invitrogen, or altered so that it is not copyright infringement. — Preceding unsigned comment added by 132.183.104.230 (talk) 17:53, 22 March 2012 (UTC)

Agreed, significant portions of this article are copy pasted directly from the invitrogen manual for their Propidium Iodide stain192.108.242.8 (talk) 18:53, 3 October 2014 (UTC)

EX - EM

How about some excitation-emission data? Kalambaki2 06:58, 19 October 2007 (UTC)

Seem to be a wrong point without scitation

In the article, "Propidium iodide (PI) binds to DNA by intercalating between the bases with little or no sequence preference and with a stoichiometry of one dye per 4–5 base pairs of DNA.", citing [2](Suzuki T, Fujikura K, Higashiyama T, Takata K (1997). "DNA staining for fluorescence and laser confocal microscopy". J. Histochem. Cytochem. 45 (1): 49–53. PMID 9010468.  ). But in the cited article, "Because PI binds to the nucleotide pair of guanine and cytosine, PI stains not only the DNAs but also the RNAs.", which is contrary to the first declaration. I didn't look at [1] and [3], but I am not sure which is right. Probably the more detailed latter description is right. Anybody has any information? —Preceding unsigned comment added by 147.46.183.191 (talk) 04:40, 22 March 2008 (UTC)

Actually, I think that it is not contradicting... it's because it confused you. What this mean is that, because PI binds to G and T (but not only!!!) it also stains the RNAs! Did you get it? it's not saying, in the second statement, that PI binds only the pair of guanine and cytosine... but because it binds it, the RNA is also marked! — Preceding unsigned comment added by 141.161.213.234 (talk) 17:00, 2 June 2011 (UTC)

Mutagen

I am not sure how to update wiki pages so someone else have at it!  :-) That... and I should be setting up a fermentation or cinac...

PI should be considered a mutagen and be handeled with care. And for your viewing pleasure here are three sources for citation.

http://www.westernu.edu/bin/safety/msds/hpc/Propidium%20iodide.pdf http://tools.invitrogen.com/content/sfs/msds/P3566_MTR-NAIV_EN.pdf http://www.immunochemistry.com/products/media/pdf/msds/MSDSPI.pdf

Thanks! 63.144.66.174 (talk) 20:34, 31 May 2011 (UTC)

Dead links

References 1 and 4 are dead links — Preceding unsigned comment added by Minnsurfur2 (talk • contribs) 15:44, 18 October 2014 (UTC)