WBC Diluting Fluid: Principle And Procedure

WBC diluting fluid is a specialized solution used in hematology laboratories to dilute blood samples for white blood cell analysis. It plays a vital role in ensuring accurate and reliable results by creating an environment that preserves the integrity of the cells during the staining process.

PRINCIPLE of WBC Diluting Fluid

WBC diluting fluid is utilized for playing out the WBC (Leucocyte) count. Glacial acidic corrosive lyses the red cells. Gentian violet somewhat stains the cores of the leucocytes. The blood example is weakened 1:20 in a WBC pipette with the diluting fluid and the cells are counted under the low force of the magnifying instrument by utilizing an including chamber. The quantity of cells in undiluted blood is accounted for per cumm (µl) of the entire blood.

Composition of WBC Diluting Fluid

1. Glacial acetic acid2.00 mL
2. Gentian Violet1.00 gm
3. Distilled water97.00 mL
4. Final pH2.2±0.2

PROCEDURE of WBC Diluting Fluid

  1. Draw fresh EDTA anticoagulated blood to the 0.4 mark.
  2. Draw diluting fluid up to the 11 mark.
  3. Mix the contents in the pipette and after 5 minutes discard a few drops.
  4. Fill the counting chamber and allow the cells to settle for 2-3 minutes.
  5. Focus on 1 of the “W” marked areas (each having 16 small squares) by turning the objective to low powder 10X.
  6. Count cells in all 4 “W” marked corner squares.

STORAGE of WBC Diluting Fluid

Store at 15°C-25°C away from bright light. The stability of the WBC diluting fluid is as per the expiry date mentioned on
the label.

calculation of WBC Diluting Fluid

Total WBC/cu mm(μl) = No. of White cell counted x dilution/Area counted x depth of fluid


(1) dilution = 20
(2) Area counted = 4 x 1sq.mm = 4 sq mm
(3) Depth of fluid = 0.1 mm (constant)

Hence no. of White cells/cu mm of whole blood = No. of cells counted x 20/4x 0.1

No. of cells counted x 50


Importance of WBC Diluting Fluid in Haematology

Accurate and reliable white blood cell analysis is crucial for diagnosing and monitoring various haematological conditions. WBC diluting fluid is a key component in achieving accurate results by providing the ideal environment for preserving cellular integrity and minimizing cell shrinkage and distortion.

By using a high-quality WBC diluting fluid, haematology laboratories can ensure that the different types of white blood cells are visible and recognizable, enabling healthcare professionals to make informed decisions about patient care.

Components of WBC Diluting Fluid

WBC diluting fluid is carefully formulated to maintain the integrity of white blood cells during the staining process. It typically consists of a buffered saline solution containing various components to optimize cell morphology and differentiation.

One essential component of WBC diluting fluid is a buffering agent, which helps maintain the pH of the solution and provides a stable environment for the cells. This is crucial for accurate staining and differentiation of white blood cells.

Another important component is a preservative, which prevents the growth of microorganisms in the diluting fluid, ensuring the longevity and reliability of the solution. Additionally, some WBC diluting fluids may contain stabilizers or anticoagulants to further enhance the preservation of cellular integrity.

How WBC Diluting Fluid is Used in the Laboratory

WBC diluting fluid is used in hematology laboratories as part of the process of preparing blood samples for white blood cell analysis. After collecting a blood sample, laboratory technicians mix a small portion of the sample with the WBC diluting fluid in a specific ratio.

The diluted sample is then placed onto a microscope slide and stained using appropriate stains to differentiate the various types of white blood cells. The WBC diluting fluid creates an optimal environment for accurate staining and differentiation, allowing for precise analysis of the white blood cells.

Common Types of WBC Diluting Fluid

There are several types of WBC diluting fluid available on the market, each with its unique formulation and characteristics. The choice of WBC diluting fluid may depend on the specific requirements of the laboratory and the preferences of the healthcare professionals using it.

One common type of WBC diluting fluid is an isotonic saline solution. This solution closely mimics the osmotic pressure of blood, providing an ideal environment for maintaining cell integrity during the staining process. Isotonic saline solution is widely used and readily available in most haematology laboratories.

Another type of WBC diluting fluid is buffered saline solution. This solution contains a buffering agent to maintain the pH of the solution, ensuring consistent and accurate staining of white blood cells. Buffered saline solution is particularly useful when analyzing blood samples that require precise pH control.

Factors to Consider When Choosing WBC Diluting Fluid

When selecting a WBC diluting fluid for your laboratory, several factors should be taken into consideration to ensure optimal results and reliability.

Firstly, compatibility with the staining system used in your laboratory is crucial. Different staining systems may require specific types of WBC diluting fluid to achieve the best results. It is important to consult the manufacturer’s guidelines or seek expert advice to ensure compatibility.

Secondly, the stability and shelf life of the WBC diluting fluid should be considered. A reliable WBC diluting fluid should have a long shelf life and consistent performance throughout its lifespan. Proper storage and handling also play a significant role in maintaining the stability of the solution.

Lastly, the cost-effectiveness and availability of the WBC diluting fluid should be evaluated. While quality is paramount, it is important to find a balance between quality and cost. Choosing a WBC diluting fluid that meets the stringent standards of haematology laboratories worldwide while being economically viable is essential.

Proper Storage and Handling of WBC Diluting Fluid

To ensure the longevity and stability of WBC diluting fluid, proper storage and handling procedures should be followed.

WBC diluting fluid should be stored in a cool and dry environment, away from direct sunlight and extreme temperatures. It is important to check the expiration date and discard any expired or deteriorated solution.

When handling WBC diluting fluid, appropriate personal protective equipment, such as gloves, should be worn to prevent contamination. The solution should be handled carefully to avoid spills or contact with skin or mucous membranes.

Troubleshooting and Common Issues with WBC Diluting Fluid

While WBC diluting fluid is designed to provide accurate and reliable results, certain issues may arise during its use. Understanding and troubleshooting these issues can help ensure consistent performance and accurate analysis.

One common issue is the presence of clots or debris in the WBC diluting fluid. This can interfere with accurate cell counting and differentiation. Regularly inspecting the WBC diluting fluid for any signs of contamination and filtering the solution if necessary can help address this issue.

Another issue that may occur is an improper dilution ratio. Using an incorrect dilution ratio can lead to inaccurate results. It is important to carefully follow the manufacturer’s instructions and use the recommended dilution ratio for optimal performance.

Alternatives to WBC Diluting Fluid

While WBC diluting fluid is the standard solution used in hematology laboratories, there may be alternative methods or solutions available for white blood cell analysis.

Some laboratories may use automated cell counters that do not require manual dilution with WBC diluting fluid. These systems use specialized reagents and technology to achieve accurate results without the need for manual dilution.

However, it is important to note that the use of alternative methods or solutions should be carefully evaluated and validated to ensure accuracy and reliability comparable to WBC diluting fluid.

What is WBC Diluting Fluid?

WBC Diluting Fluid is a solution used in haematology to dilute blood samples for accurate white blood cell count.

Why is WBC Diluting Fluid necessary in blood analysis?

WBC Diluting Fluid ensures that blood samples are appropriately diluted, allowing for accurate and reliable white blood cell counts.

How is WBC Diluting Fluid different from other diluents?

WBC Diluting Fluid is specifically formulated to preserve white blood cells and provide optimal conditions for their accurate enumeration.

What are the components of WBC Diluting Fluid?

The formulation typically includes a mixture of reagents designed to maintain the integrity of white blood cells during the dilution process.

How is WBC Diluting Fluid used in a laboratory setting?

It is added to a blood sample in a controlled manner to dilute the sample, making it suitable for analysis using automated haematology analyzers.

Does the choice of WBC Diluting Fluid impact test results?

Yes, the choice of diluting fluid can affect the accuracy of white blood cell counts. WBC Diluting Fluid is selected based on its compatibility with specific laboratory instruments.

Is WBC Diluting Fluid suitable for all haematology analyzers?

No, different analyzers may require specific types of diluting fluids. It’s crucial to use the fluid recommended by the analyzer’s manufacturer.

Can WBC Diluting Fluid be stored for extended periods?

Storage conditions vary, but generally, WBC Diluting Fluid should be stored according to the manufacturer’s instructions to maintain its effectiveness.

Are there any safety precautions when handling WBC Diluting Fluid?

Follow standard laboratory safety protocols. Wear appropriate personal protective equipment and handle the fluid in a well-ventilated area.

Can WBC Diluting Fluid be used in point-of-care testing?

In most cases, it is designed for use in centralized laboratories with automated haematology analyzers. Point-of-care testing may require different protocols and solutions.

Spread the love

Leave a Comment