DAPI (4',6-diamidino-2-phenylindole, dihydrochloride), 10 mg, 10 mg - FAQs

View additional product information for DAPI and Hoechst Nucleic Acid Stains - FAQs (H21491, H21492, H3569, H1398, D3571, H1399, D21490, D1306, 62248, 62249, H3570)

8 product FAQs found

我注意到，当我在click反应后用DAPI染色细胞并检测EdU的掺入时，相比于我的无click反应对照样品，DAPI信号非常低。是什么原因导致DAPI信号降低？

click反应中的铜离子使得DNA少量变性（虽然没有BrdU检测所需要的程度），这会影响到包括DAPI和Hoechst染色剂在内的DNA染料的结合亲和力。这种影响只会在传统的EdU试剂盒中出现，而Click-iT Plus EdU试剂盒由于采用的铜离子浓度低，不会出现这种现象。 

DAPI和Hoechst 染料非常相似，该如何选用？

DAPI是一种非常普通的蓝色核复染荧光染料，能对固定和通透的细胞和组织的细胞核进行非常明亮的标记。遗憾的是，人们普遍认为它是介于半通透性到非通透性之间的染色剂，对活细胞的染色效果也不一致。Hoechst 33342染料是细胞通透性染料，与DAPI染色有相似的染色结合机制和荧光颜色；它是活细胞成像的首选，且对固定细胞的标记效果和DAPI一样好。

My DAPI labeled samples have a strong blue background signal immediately after mounting. What can I do to fix this?

Some mounting medias can have strong blue autofluorescence. If you are seeing a high blue background, it could be coming from the mountant. Try labeling the sample and view it before (using a wet mount in buffer) and after mounting to determine if the background signal is coming from the mounting media or the sample itself.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

Is DAPI a good live-cell nuclear label?

DAPI is considered a semi-permeant/impermeant nucleic acid stain. Staining of nucleic is dependent upon the cell line in its performance. Some cell lines will label with DAPI, others not at all, and others label inconsistenly. Instead, we recommend using either Hoechst 33342 or Hoechst 33258, which have the same wavelength and binding mode as DAPI (at the A-T minor groove) but are readily cell-permeant.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

I want to label the nuclei of live cells and track them over time. Can I use DAPI for this?

We do not recommend doing this. DAPI is considered to be a semi-permeant/impermeant nucleic acid stain. DAPI staining of live cells may be inconsistent. It is best used as a counterstain for fixed samples. Other cell permeable nucleic acid stains, such as Hoechst or the SYTO dyes may affect cellular function.

For mammalian cells, we recommend using the CellLight Nucleus transduction reagents, available in CFP, GFP and RFP. With these reagents, the cells are transduced overnight in a single labeling step and the next day the nuclei will fluoresce. The label may be retained for 3-5 days and should not affect cell function. Cytoplasmic cell tracking dyes such as the CellTracker dyes may also be used.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

Can DAPI (4',6-Diamidino-2-Phenylindole, Dihydrochloride) (Cat. No. D1306) solution be filtered with a 0.22 µm membrane filter?

DAPI (4',6-Diamidino-2-Phenylindole, Dihydrochloride) (Cat. No. D1306) solutions can be filtered with an inert or low-binding 0.22 µm membrane filter if the stock solution is in water or buffer.

Find additional tips, troubleshooting help, and resources within our Cell Viability, Proliferation, Cryopreservation, and Apoptosis Support Center.

I notice that when I post-stain my cells with DAPI after performing the click reaction to detect EdU incorporation, my DAPI signal is lower compared to my no-click reaction control samples. What causes the reduction in DAPI signal?

The copper in the click reaction denatures DNA to a small extent (although not as much as is required for efficient BrdU detection), which can affect the binding affinity of DNA dyes including DAPI and Hoechst stain. This effect should only be apparent with the classic EdU kits and not the Click-iT Plus EdU kits, which use a lower copper concentration.

Find additional tips, troubleshooting help, and resources within our Cell Viability, Proliferation, Cryopreservation, and Apoptosis Support Center.

DAPI and Hoechst dyes are quite similar to each other. Why would I choose one over the other?

DAPI is a very common blue-fluorescent dye for nuclear counterstaining and gives very bright labeling on nuclei in fixed and permeabilized cells and tissues. However, it is considered to be a semi-permeant to impermeant stain and provides inconsistent staining of live cells. Hoechst 33342 dye is cell-permeant and stains with the same binding mechanism and fluorescent color; it is preferred for live-cell imaging and is just as good as DAPI for fixed cell labeling.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.