Fuchsine base (monohydrochloride)  (Synonyms: Magenta base monohydrochloride; Basic Fuchsin monohydrochloride; Rosaniline Base monohydrochloride)

Fuchsine base (Magenta base; Basic Fuchsin) monohydrochloride is a triaminotriphenylmethane dye. Fuchsine base monohydrochloride has anesthetic, bactericidal and fungicidal properties. Fuchsine base monohydrochloride can be used for the staining of collagen, muscle, mitochondria and tuberculosis. Fuchsine base monohydrochloride is commonly used as a counterstain in Gram staining^[1][2].

Protocol (The following introduces the method of using this product for cell (suspected bacterial infection)/bacteria staining through Gram staining as an example. This plan only provides a guideline and should be modified according to your specific needs.)
1.1 Sample Collection
Samples were collected strictly following aseptic operation techniques to obtain isolated bacteria/cell samples.
1.2 Required Reagents
Primary staining agent: Crystal violet (HY-B0324A)
Mordanting agent: Gram's iodine solution
Decolorizing agent: Acetone/ethanol (50:50 volume ratio)
Recoloring agent: 0.1% alkaline fuchsine solution (Fuchsine base monohydrochloride)
2. Bacterial Staining
2.1 Use a inoculation loop to transfer the suspension culture onto a microscope slide.
2.2 Add crystal violet staining agent to the fixed culture.
2.3 Iodine solution is applied to cover the smear for 10 to 60 seconds. After removing the iodine solution, rinse the slide with running water. Then, blot off the excess water on the surface.
2.4 Add a few drops of decolorizing agent to the slide. Then rinse the slide with clean water for 5 seconds. To prevent excessive decolorization of Gram-positive bacteria, if the slide no longer shows color when the solvent flows over it, stop adding the decolorizing agent immediately.
2.5 The smear is re-stained with an alkaline brilliant red solution for approximately 40 to 60 seconds. Then, the brilliant red solution is washed off with clean water, and the excess moisture is absorbed using paper towels. Alternatively, the slide can be left to air dry naturally after removing the excess moisture.
3. Microscope Observation
3.1 Use the oil immersion method to observe the slide under the microscope. Initially, a 40× objective lens should be used to examine the slide to assess the distribution of the smear, and then a 100× oil immersion objective lens should be used for further inspection.
3.2 The staining of white blood cells and macrophages was Gram-negative.
3.3 The squamous epithelial cells show positive Gram staining.
Note: Organisms that appear purple-brown in color after primary staining under the microscope are Gram-positive bacteria, while those that do not absorb the primary staining agent and appear red under the microscope are Gram-negative bacteria.

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

337.85

C₂₀H₂₀ClN₃

632-99-5

Solid

NC1=CC=C(/C(C2=CC=C(N)C=C2)=C3C=CC(C=C\3)=N)C=C1C.[H]Cl

Room temperature in continental US; may vary elsewhere.

RT, sealed storage, away from moisture and light

*In solvent : -80°C, 6 months; -20°C, 1 month (RT, sealed storage, away from moisture and light)

* Please refer to the solubility information to select the appropriate solvent. Once prepared, please aliquot and store the solution to prevent product inactivation from repeated freeze-thaw cycles.
Storage method and period of stock solution: -80°C, 1 year; -20°C, 6 months. When stored at -80°C, please use it within 1 year. When stored at -20°C, please use it within 6 months.

• [1]. Gupta VK, et al. Adsorption of basic fuchsin using waste materials--bottom ash and deoiled soya--as adsorbents. J Colloid Interface Sci. 2008 Mar 1;319(1):30-9.  [Content Brief]

  [2]. Tripathi N, et al. Gram Staining. 2025 Mar 28. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan–.  [Content Brief]