Weigert Elastin Staining Kit 

Elastic fibers are primarily found in the walls of arteries, alveolar walls, and skin. They appear yellow in fresh tissues and possess strong birefringence. Common methods for staining elastic fibers in histological studies include Gomori aldehyde fuchsin method, resorcin-fuchsin, Victoria Blue, and Weigert's iron hematoxylin method, among others.

The staining principle of Weigert's elastic fiber staining solution lies in the interaction between resorcinol fuchsin and iron ions, forming a Lake complex. The free amino groups of the complex tightly bind with the hydrogen bonds in elastic fibers, resulting in the fibers appearing black. This method effectively reveals the morphology and changes in elastic fibers within skin tissues, such as elastic fiber nevus, skin granulomas, and scleroderma. It is also useful in determining the condition of endocardium and arterial lesions, observing elastic fiber proliferation or destruction in diseased tissues, and differentiating tumor components such as elastic fiber tumors. After staining, mature elastic fibers within the tumor can be clearly visualized.

MCE Weigert Elastin Staining Kit combines Weigert Resorcinol Fuchsin Staining Solution with Van Gieson (VG) Staining Solution. Weigert Resorcinol Fuchsin Solution is mainly used for staining elastic fibers, Van Gieson (VG) Solution is used for collagen fiber staining. The principle of VG staining is based on differences in the size of anionic dye molecules and the permeability of tissues. Picric acid (PA) has the smallest molecular weight and preferentially enters dense structures. Ponceau Red or acid fuchsin has a relatively larger molecular weight and primarily binds to collagen fibers, while light green has the largest molecular weight and stains other tissue components. After VG staining, collagen fibers appear red, while muscle fibers and cytoplasm appear yellow, enabling a clear distinction between tissue components.

Weigert Resorcinol Fuchsin Staining Solution: 4°C, 1 year. Protected from light.

Acidic Ethanol Differentiation Solution, Fuchsin Staining Solution, Saturated Picric Acid Solution: RT, 1 year. Protected from light.

Reagents Preparation

Xylene, neutral mounting medium or mounting reagent, graded ethanol solutions, distilled water, etc.

Procedure

Note: It is recommended to perform a pre-test before formal staining to determine the optimal staining conditions for tissue sections.

1. Deparaffinization and Hydration: Deparaffinize the tissue sections using routine methods, and then rehydrate them in 95% ethanol for later use.

2. Weigert Resorcinol Fuchsin Staining: Immerse the tissue sections in Weigert Resorcinol Fuchsin Staining Solution for 1–3 h at room temperature or 0.5–1 h at 56°C. Subsequently, rinse briefly with water.

Note: Ensure the staining container is covered during immersion.

3. Differentiation: Treat the sections with 95% ethanol to remove the cytoplasmic background staining, and continue differentiating until the staining solution is removed. If differentiation is inadequate, further differentiate for 2–3 s using acidic ethanol differentiation solution, followed by rinsing with water for 5–10 min.

4. Van Gieson Staining

4.1 Preparation of Van Gieson staining solution: Mix Fuchsin Staining Solution and saturated Picric Acid solution at a ratio of 1:9 (v/v).

Note: It is recommended to prepare the Van Gieson staining solution fresh before use.

4.2 Van Gieson staining: Immerse the sections in the prepared Van Gieson solution for 30 s. Rinse briefly with water afterward.

Note: After Van Gieson staining, the water rinse and subsequent dehydration in 95% ethanol should be carried out rapidly to avoid the removal of fuchsin and picric acid.

5. Dehydration: Quickly dehydrate sections in 95% ethanol, followed by absolute ethanol three times, each for 5–10 s.

6. Clearing and Mounting: Clear the sections in xylene or a suitable clearing agent, then mount with neutral mounting medium. Observe under a microscope and acquire images as needed.

Interpretation of Staining Results

1. Elastic Fibers: Deep blue to black.

2. Collagen Fibers: Bright red.

3. Muscle Fibers, and Erythrocytes: Yellow.

1. Most fixatives are compatible with this staining method, but it is important to note that fixatives containing chromium salts may result in lighter staining and a tendency for the stain to diffuse.

2. Differentiation in acidified ethanol should be adjusted according to section thickness, tissue type, and the age of the section.

3. Reagents should be used as soon as possible after opening to avoid potential effects on experimental results.

4. This product is for R&D use only, not for drug, household, or other uses.

5. For your safety and health, please wear a lab coat and disposable gloves to operate.