DAPI dilactate  (Synonyms: 4',6-Diamidino-2-phenylindole dilactate)

DAPI (dilactate) is a blue fluorescent dye that preferentially binds dsDNA and binds to minor groove AT clusters. DAPI (dilactate) is combined with dsDNA, and the fluorescence was enhanced about 20-fold. DAPI (dilactate) can be used to identify the cell cycle and specifically stains the nucleus but not the cytoplasm. DAPI (dilactate) form is more soluble in water than DAPI (dihydrochloride) form. ^[1][2]

General protocol
1. Preparation of DAPI dilactate working solution
1.1 Preparation of stock solution
Dissolve 5 mg DAPI dilactate in 1 mL ddH₂O to obtain 5 mg /mL stock solution (DAPI, dilactate 10.9 mM).
Note: It is recommended to store the stock solution at -20°C or -80°C in the dark and avoid repeated freezing and thawing.
1.2 Preparation of DAPI dilactate working solution
The stock solution was diluted 1:5000 in PBS to 1 μg/mL. Store the working solution at 4 °C.
Note: Please adjust the concentration of DAPI dilactate working solution as needed
2. Cell staining
2.1 Suspension cells (96-well plate)
a. Centrifuge at 1000 g for 3-5 min at 4°C and discard the supernatant. Wash with PBS twice, 5 minutes each time. The cell density is 1×10⁶/mL.
b. Add 1 mL of working solution and incubate at room temperature for 3-10 minutes.
c. Centrifuge at 400 g for 3-4 minutes at 4°C and discard the supernatant.
d. Wash 2 times with PBS, 5 min each.
e. Resuspend cells in serum-free cell culture medium or PBS. Fluorescence microscopy or flow cytometry observation.
2.2 Adherent cells
a. Adherent cells were cultured on sterile coverslips.
b. Remove the coverslip from the medium and aspirate excess medium. c. Add 100 μL of working solution, shake gently to completely cover the cells, and incubate at room temperature for 3-10 minutes.
d. Wash 2 times with medium, 5 min each. Fluorescence microscope or flow cytometry observation.
Precautions
For long-term storage the stock solution can be aliquoted and stored at ≤–20°C. For shortterm storage the solution can be kept at 2–6°C, protected from light. When handled properly, DAPI solutions are stable for at least six months.

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

457.48

C₂₂H₂₇N₅O₆

28718-91-4

O=C(C(C)O)O.N=C(C1=CC=C(C2=CC3=CC=C(C(N)=N)C=C3N2)C=C1)N.O=C(C(C)O)O

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Kapuscinski J. DAPI: a DNA-specific fluorescent probe. Biotech Histochem. 1995 Sep;70(5):220-33.  [Content Brief]

  [2]. Nazaroff CD, et al. Assessment of Lung Eosinophils In Situ Using Immunohistological Staining. Methods Mol Biol. 2021;2223:237-266.  [Content Brief]