Overview
ISO 12772:1997: Laboratory glassware - Disposable microhaematocrit capillary tubes establishes international requirements for two types of disposable glass capillary tubes used in laboratory settings. Designed for single use, these microhaematocrit tubes are primarily intended for microhaematocrit tests and other analyses that require the separation of plasma and cells. The standard covers classification, construction, dimensions, anti-coagulant coatings, labelling, and colour coding to ensure safety, consistency, and reliability in laboratory diagnostics.
Key Topics
- Classification: ISO 12772 specifies two types of tubes:
- Type I: Coated with anti-coagulant (e.g., lithium heparin, sodium heparin)
- Type II: Uncoated
- Material and Construction:
- Glass must meet prescribed hydrolytic resistance standards (conforming to ISO 719, class HGB 3 or better)
- Tubes must be free from visible defects and internal stresses
- Both ends of the tube should be open, and walls uniformly thick
- Dimensions:
- Defined specifications for length, internal diameter, and wall thickness
- Bore variability is limited to ensure analytical reliability
- Anti-Coagulant Coatings (Type I):
- Inner surfaces must be evenly coated with an effective anti-coagulant
- Activity and efficacy of coatings must be verified as described in the annexes
- Colour Coding and Marking:
- Type I tubes use specific colours to denote anti-coagulant type (e.g., orange for lithium heparin)
- Type II (uncoated) tubes may be blue
- Packaging and tubes must be clearly labelled for identification, traceability, and compliance
Applications
ISO 12772:1997 is essential for manufacturers, laboratories, and healthcare facilities that require reliable microhaematocrit measurement and other blood separation analyses. Common applications include:
- Microhaematocrit Testing: Used to determine the proportion of red blood cells in blood samples
- Plasma and Cell Separation: Suitable for tests involving blood fractionation
- Quality Assurance in Diagnostics: Ensures consistency and safety in laboratory results by standardizing materials and procedures
- Single-Use Laboratory Supplies: Reduces contamination risk and supports infection control in clinical, research, and medical facilities
Adhering to ISO 12772 promotes global compatibility, safety in blood handling, and reliable test outcomes. The standard also supports laboratory accreditation and regulatory compliance for glassware manufacturers and healthcare providers.
Related Standards
The implementation and requirements of ISO 12772:1997 are aligned with several complementary international standards, including:
- ISO 719: Hydrolytic resistance of glass grains - Method of test and classification
Ensures glass quality and chemical resistance, critical for laboratory safety.
- ISO 8417: Laboratory volumetric instruments - Principles for disposable volumetric articles
Guides the design and construction of single-use laboratory glassware for consistent performance.
- National Committee for Clinical Laboratory Standards (NCCLS) H24-T: Provides additional reference methods for evaluating anti-coagulant effectiveness.
Practical Value
Applying the guidelines in ISO 12772:1997 supports:
- Quality manufacturing of disposable microhaematocrit capillary tubes
- Accurate and reproducible blood testing, supporting healthcare diagnostics
- Enhanced user safety through proper labelling and design requirements
- International trade by harmonizing specifications for laboratory glassware
For laboratories and manufacturers, compliance with ISO 12772 ensures products meet global expectations for performance, safety, and quality in medical diagnostics and research.
Keywords: ISO 12772, disposable microhaematocrit tubes, laboratory glassware, capillary tubes, anti-coagulant coating, single-use laboratory equipment, blood separation, clinical diagnostics, quality standards