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Buffers & Dyes
Cellular Dyes

X-34 #74193

Citations (0)
  1. IF
Confocal analysis of cortex from the 5XFAD mouse model of Alzheimer's disease, labeled with X-34 (left, cyan) and co-labeled with TMEM119 (E4B9S) Mouse mAb #98778 (right, green) and DRAQ5 #4084 (right, red).

Product Usage Information

Supplied Reagents:

1. X-34: Create a 5 mM stock solution of X-34 (200X) using the X-34 diluent. Create a 25 µM staining solution by further diluting the 5 mM stock solution using the X-34 diluent.
Note: X-34 diluent (40% EtOH, pH 10) is the recommended solvent for staining. A slight precipitate may be present, but will not interfere with the product's performance.

Additional Reagants (Not Supplied)

1. X-34 diluent (40% EtOH, pH 10): Combine 20 mL of EtOH in 29.5 mL of dH2O. Add 1 µL of 5M NaOH dropwise until the solution reaches pH 10. Bring the final volume of X-34 diluent to 50 mL with dH2O.
2. Differentiation buffer: 50 mM NaOH, 80% EtOH

1. Stain slides in 25 µM X-34 staining solution for 30 min at room temperature in the dark.
2. Rinse slides three times in dH2O.
3. Incubate for 2 min in the differentiation buffer.
4. Rinse slides three times in dH2O.
5. If desired, proceed with immunostaining.
6. Mount and image.


Store lyophilized at 4ºC, desiccated. In lyophilized form, the product is stable for 12 months.

Fluorescent Properties

  • Excitation maximum = 367 nm/Emission Maximum = 497 nm

Product Description

X-34 is a lipophilic and highly fluorescent marker used to examine pathological changes in Alzheimer’s disease (AD). This cellular dye was developed as a derivative of Congo red to be more compatible with in vivo applications. By replacing the azo groups (nitrogen-to-nitrogen double bonds) in Congo red with carbon-to-carbon double bonds and having more lipophilic salicylic acid groups, X-34 has proven to be highly fluorescent and have increased membrane permeability. X-34 detects β-sheet structures and labels amyloid plaques, neurofibrillary tangles (NFTs), neuropil threads, and vascular amyloid in AD brains (1).
Molecular Weight 402.4 g/mol
Purity ≥ 90%
Molecular Formula C24H18O6
CAS 215294-98-7
Solubility Soluble in DMSO at 2 mg/mL.

Limited Uses

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For Research Use Only. Not for Use in Diagnostic Procedures.
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To Purchase # 74193
Cat. # Size Qty. Price
5 mg