Oil Red O Staining Kit for Cell Smears 

Lipids refer to neutral fats, lipids, and their derivatives, which share a common physical property: they are insoluble in water but soluble in organic solvents. Common dyes used for lipid staining in histology include Sudan I, Sudan III, Sudan IV, Sudan Black B, and Oil Red O. While traditional methods often use Sudan dyes, Oil Red O provides better visualization, offering clearer and more distinct staining, making it more suitable for fat staining.

Oil Red O (ORO) is a lipid-soluble azo dye that dissolves in and binds to fats (such as triglycerides), forming orange-red lipid droplets. The staining principle is based on the fact that lipid-soluble dyes have a higher solubility in tissue lipids than in the solvent, allowing the dye to transfer from the solution into the lipid droplets in tissues. Oil Red O is primarily used to display fat degeneration and abnormal lipid deposition in tissues and organs. It is particularly useful for the following applications: Fatty degeneration in solid organs such as the liver, heart, and kidneys; Accumulation of neutral fat droplets within cells; Lipid deposition beneath endothelial cells; Lipid identification in fat emboli; Tumor diagnosis and differentiation in adipose tissue.

MCE Oil Red O Staining Kit for Cell Smears effectively stains lipid droplets of various sizes, including smaller lipid droplets, and preferentially adsorbs dye from the solvent. It is suitable for staining oil red O in cell smears, bone marrow smears, fluid smears, blood smears, and other samples. When using the kit, specimens should not be fixed with fixatives containing ethanol. If fixation is required, 10% formalin can be used. The positive staining result for fat typically appears orange-yellow to red, with the exact color varying depending on the lipid concentration.

Fixative Solution, ORO Staining Solution A, Mayer Hematoxylin Solution, ORO Wash Buffer: 4°C, 1 year. Protected from light.

ORO Staining Solution B: RT, 1 year. Protected from light.

Reagents Preparation

60% Isopropanol, Distilled Water, Glass Slides, etc.

Procedure

1. Sample Fixation: Prepare fresh bone marrow, blood, or cell smears and fix them with Fixative Solution for 10-15 min.

2. Air Drying: Remove the smears and allow them to air dry for 10-15 min.

3. Oil Red O Staining

3.1 Preparation of Oil Red O Working Solution: ORO Staining Solution A and ORO Staining Solution B in a 3:2 (v/v) ratio to prepare the working solution.

Note: The Oil Red O working solution is unstable and may precipitate. It is recommended to prepare it fresh before use. After preparation, let it stand for 20-40 min or centrifuge at 3,000 rpm for 10 min and use the supernatant for staining.

3.2 Oil Red O Staining: Immerse the smear in the prepared Oil Red O working solution for 10-15 min.

4. Isopropanol Treatment: Rinse the smear with 60% isopropanol for 20-30 s, followed by a rinse with distilled water.

5. Mayer Hematoxylin Staining: Counterstain the nuclei with Mayer Hematoxylin Solution for 2-5 min.

Note: Do not over-stain with hematoxylin.

6. (Optional) Washing: Wash the smear with ORO wash buffer for 1 min.

7. Rinsing and Observation: Rinse the smear with distilled water for 8-10 min, allow them to air dry, and then observe under the microscope.

Note: Staining results should not be stored for long periods; observe and capture images as soon as possible.

Interpretation of Staining Results

1. Neutral Fat: Orange-red or Red-orange.

2. Phospholipids: Pink.

3. Cell Nuclei: Blue.

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

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

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