EDTA (Ethylenediaminetetraacetic acid) tubes are the unsung heroes of diagnostic laboratories, ensuring accurate blood sample collection and preservation. You’ve probably seen them—those vibrant tubes used for blood testing. But did you know there are different EDTA tube sizes and colors, each designed for specific purposes? This guide covers everything from the basics to advanced details on EDTA Tube Sizes and Uses, and applications.
What Are EDTA Tubes?
EDTA tubes are specially designed vacuum-sealed tubes that contain an anticoagulant—EDTA. The purpose? To prevent blood from clotting during sample collection, making it easier to analyze whole blood or plasma. These tubes are indispensable in hematology, biochemistry, and immunology labs.

Why EDTA?
So, why EDTA? This anticoagulant binds to calcium ions in the blood, preventing clot formation. It ensures the blood sample remains unchanged, which is crucial for accurate testing. Common applications include:
- Complete Blood Count (CBC) tests.
- Blood Typing and Cross-Matching.
- DNA and RNA Analysis.
EDTA Tube Sizes and Colors
Did you know EDTA tubes come in different sizes and cap colors? Let’s break it down:
EDTA Tube Sizes
The volume of EDTA tubes typically ranges between 2 mL to 10 mL. Here’s a quick overview of the common sizes:
- 2 mL Tubes: Ideal for pediatric use or when only a small sample is required.
- 5 mL Tubes: Standard size used in most diagnostic labs.
- 10 mL Tubes: Used when larger volumes of blood are needed for tests.
Note: For detailed product information, visit EDTA Tube Products and Siny Medical EDTA Tubes.
EDTA Tube Colors and Their Uses
The color of the tube’s cap indicates its specific use. Here’s what each color means:
- Lavender/Purple Cap: Used for CBC and hematology tests.
- Pink Cap: Preferred for blood banking and cross-matching.
- White/Plasma Separator Tubes (PST): Ideal for plasma-based tests like molecular diagnostics.
- Tan Cap: Specialized for lead testing.
- Royal Blue Cap: Used for trace element and heavy metal analysis.
The color-coded caps are standardized across the industry, making it easier for medical staff to use the correct tube.
The Use of Different Vacuum EDTA Blood Collection Tube
Volume/ml | Size/mm | Additive | Separator | Material | Cap Color | Closure |
2ml | 13X75 | EDTA K2 / EDTA K3 | / | PET/GLASS | Purple Cap Tube | Safety Cap+Rubber or Rubber Stopper |
3ml | 13X75 | EDTA K2 / EDTA K3 | / | |||
4ml | 13X75 | EDTA K2 / EDTA K3 | / | |||
5ml | 13X75 | EDTA K2 / EDTA K3 | / | |||
6ml | 13X100 | EDTA K2 / EDTA K3 | / | |||
7ml | 13X100 | EDTA K2 / EDTA K3 | / | |||
8ml | 16X100 | EDTA K2 / EDTA K3 | / | |||
9ml | 16X100 | EDTA K2 / EDTA K3 | / | |||
10ml | 16X100 | EDTA K2 / EDTA K3 | / | |||
If You Need Customized Vacuum Blood collection tube, Please Contact Us |
Uses of EDTA Tubes
EDTA tubes have an impressive range of uses in the medical and research fields. Here’s where they shine the most:
Hematology
- Complete Blood Count (CBC): Measures red and white blood cells, hemoglobin, hematocrit, and platelets.
- Erythrocyte Sedimentation Rate (ESR): Helps detect inflammation in the body.
Molecular Diagnostics
- EDTA tubes are perfect for isolating DNA and RNA for genetic testing. Their anticoagulant properties help preserve nucleic acids for accurate analysis.
Blood Banking
- Tubes with pink caps are commonly used for cross-matching and blood typing, ensuring compatibility for transfusions.
Specialized Testing
- Lead testing (tan cap tubes) and trace element analysis (royal blue cap tubes) require precision, and EDTA tubes fit the bill.
Features of EDTA Blood Collection Tubes
Additives: The primary additive in these tubes is either EDTA K2 or EDTA K3, both of which effectively prevent blood coagulation by binding calcium ions.
Material: Most tubes are made from PET (Polyethylene Terephthalate) or glass, ensuring durability and resistance to breakage.
Cap Color: The standard color for EDTA tubes is purple, which helps in easy identification during laboratory processes.
Closure Type: These tubes typically feature a safety cap with a rubber stopper, providing a secure seal to prevent leakage and contamination.
Where to Source EDTA Tubes?
Looking for high-quality EDTA tubes? Two trusted suppliers are:
- EDTA Tube: A reliable provider offering a wide range of tube sizes and colors.
- Siny Medical: Known for their medical-grade EDTA tubes and accessories.
Both platforms provide detailed product descriptions and support, making your purchase decisions easier.
Final Thoughts
EDTA tubes are an essential part of diagnostic testing, offering reliability and versatility across various medical applications. Understanding their sizes, colors, and uses can significantly improve accuracy in labs and healthcare settings. If you’re looking to stock up on EDTA tubes, visit trusted suppliers like EDTA Tube and Siny Medical.
For additional resources, you can explore:
Remember, choosing the right EDTA tube is crucial for test accuracy and sample preservation. Always double-check the specifications before making a selection.
FAQs
What’s the shelf life of EDTA tubes?
Most EDTA tubes have a shelf life of 12–24 months if stored correctly.
Can I reuse an EDTA tube?
No, EDTA tubes are single-use only to prevent contamination and ensure test accuracy.
Are EDTA tubes safe for pediatric patients?
Yes, smaller sizes like 2 mL are specifically designed for pediatric use.
What’s the difference between lavender and pink EDTA tubes?
Lavender tubes are used for hematology tests, while pink tubes are designed for blood banking and cross-matching.
How do I choose the right EDTA tube for my needs?
Refer to the tube’s cap color and volume to match the test requirements. Consult with your supplier for further guidance.