DRAQ5™ (ab108410)

Merci de nous avoir contactés. D'après les données expérimentales DRAQ5 est excitable à 488nm mais comme le montre le spectre, la longueur d'onde optimale est 647 nm. Malgré la faible absorbance, l'excitation à 488nm permet d'offrir un bon coefficient de variation pour une utilisation en cytométrie en flux. J'espère que ces informations vous seront utiles. N'hésitez pas à nous contacter de nouveau si vous avez d'autres questions.  

Thank you for contacting us with your question. The cell permeable fluorescent DNA dye DRAQ5, ab108410, can be used to analyze the ploidy of a cell population- https://www.abcam.com/DRAQ5™-50-µl-5mM-ab108410.html DNA dyes are a common tool for cell cycle and ploidy analysis, and there are several publications explaining the method and protocol, such as the following articles- http://www.horizonpress.com/cimb/v/v3/v3n303.pdf http://onlinelibrary.wiley.com/doi/10.1002/cyto.a.10051/full I hope this information will be useful, but please let me know if you have any questions and I'll be happy to help.

Thank you for your inquiry. DRAQ5 labels dsDNA. It intercalates DNA at the A-T sites and will do so stoichiometrically. Although DRAQ5 probably does label some RNA, in practice this is not seen – mainly due to the very low quantum yield of DRAQ5 and the distributed presence of RNA in a cell. So for all intents and purposes, DRAQ5 can be considered as a dsDNA dye. You may wish to refer to McGrath et al, JIM 2008.   They helpfully used a combination of DRAQ5 (DNA) and Thiazole Orange (RNA) to analyze the lineage progression of erythropoiesis (analysed on the Amnis ImageStream). http://www.ncbi.nlm.nih.gov/pubmed/18539294 I hope this information helps. Please contact us with any other questions.

Thank you for your inquiry. DRAQ7 is a LIVE cell impermeant far-red DNA dye. It can be used to identify permeable cells in a mix of live and dead cells (i.e. the dead cells) – but in a preparation of fixed cells, all of the cells will be permeant and therefore all will be stained with DRAQ7. If you are trying to differentiate between live and dead cells in a sample (before fixation), then you could simply add DRAQ7 prior to fixation and identify (count) the number of DRAQ7 labelled cells – they will be the dead cells. After fixation, the DRAQ7 will enter all of the cells – and you can now get a total count. Subtraction of dead cell count from total count will give the live cell count.  There are of course issues here – especially if the same sample cannot be used prior to and after fixation. Another idea might be to use DRAQ7 and DRAQ5 (ab108410) in sequence prior to fixation. Adding DRAQ7 first will give the dead cell count. Adding DRAQ5 will then give the total count – and usefully both dyes are in the far-red (same emission). Subtraction of dead count from total count will give the live count. The sample could then be fixed. I hope that this is helpful. Please let me know if you have any other questions.

Thank you for contacting us. DRAQ5 can be used as replacement for Hoechst for staining live or fixed cell. In case of apoptotic differentiation we would recommend using DRAQ7 dye, this dye does not penetrate living cells so it will only stain dead and membrane-compromised cells. The catalogue number of DRAQ7 is ab109202; https://www.abcam.com/DRAQ7™-1ml-0-3mM-ab109202.html I hope this information is helpful to you. Please do not hesitate to contact us if you need any more advice or information.

Thank you for contacting us. I have received the following response from the lab: We would suggest to approach this as follows ... Treat the cell culture with 1-3 uM DRAQ7 during the incubation, image to enumerate the dead/leaky cells at the required end-point and then immediately add 3-5 uM DRAQ5, allow to stain for 5 -10 min and measure again for ALL events, IN THE SAME CHANNEL. The two images will show: 1) dead/apoptotic cells, DRAQ7+ 2) all nucleated cells, DRAQ5+ The two images can be artificially colored to reveal the live cells, when merged. The DRAQ7 positive events can be monitored by imaging in real time during the culture period to observe the progression and dynamics of cell damage and death. Red excitation will limit the risk of DNA damage that is common to UV excited probes. The Draq5 would need being added at the very end of the 24 hour time point, after the last DRAQ7 read. It is tricky to measure the live cells at the beginning of the experiment (i.e. around 0 or 1 hour). We would consider using phase contrast to estimate total cells and subtract the initial DRAQ7 positives. There is no real way to remove Draq5 after incubation for 10 min or so. Once it’s labelled to DNA then it’s there “irreversibly” due to high affinity. As Draq7 is not cytotoxic, an incubation with Draq7 for 24 hours would be fine. DRAQ7 only enters cells that are membrane-compromised. Our data show effectively no toxicity after 96 hours of proximity to proliferative cells. I hope this information is helpful to you. Please do not hesitate to contact us if you need any more advice or information.

Thank you for your enquiry. The following publications have used DRAQ5™ dye: Smith PJ. Blunt N. Wiltshire M. Hoy T. Teesdale-Spittle P. Craven MR. Watson JV. Amos WB. Errington RJ. Patterson LH. Characteristics of a novel deep red/infrared fluorescent cell-permeant DNA probe, DRAQ5™, in intact human cells analyzed by flow cytometry, confocal and multiphoton microscopy. Cytometry. 40(4):280-91, 2000. Wiltshire M. Patterson LH. Smith PJ. A novel deep red/low infrared fluorescent flow cytometric probe, DRAQ5NO™, for the discrimination of intact nucleated cells in apoptotic cell populations. Cytometry. 39(3):217-23, 2000. Smith PJ. Wiltshire M. Davies S. Patterson LH. Hoy T. A novel cell permeant and far red-fluorescing DNA probe, DRAQ5™, for blood cell discrimination by flow cytometry. Journal of Immunological Methods. 229(1-2):131-9, 1999 There is a protocol available on the protocols tab on the online datasheet:   https://www.abcam.com/ps/products/108/ab108410/documents/ab108410%20DRAQ5%20protocol%20(Website).pdf With regards to ordering from Greece, we do not have a Greek distributor and you can place your order directly with our UK office. Email orders@abcam.com. I hope this will be helpful to you. If you have any further questions, please do not hesitate to contact us.