Overview
ISO 7550:1985 defines international standards for disposable micropipettes used in laboratory settings. This standard specifies the requirements for two distinct types of disposable glass micropipettes used for precise volumetric measurements:
- Type I: Micropipettes with a graduation line and colour code, calibrated to contain a specific volume when filled to the graduation line.
- Type II: Micropipettes without markings, calibrated to contain the nominal volume when filled completely.
These micropipettes are designed for single use and provide a cost-effective and reliable means for accurate liquid handling in laboratories. The standard details requirements on dimensions, construction, capacity definitions, performance testing for accuracy and repeatability, as well as appropriate marking and colour coding.
Key Topics
Types and Capacities
- Type I micropipettes feature a visible graduation line and colour band; volumes are measured by filling to the graduation line.
- Type II micropipettes have no markings and are filled completely to reach the nominal volume.
- Capacities range across typical laboratory volumes - Type I: 5 to 200 µl, Type II: 1 to 100 µl, with additional volumes possible per manufacturing needs.
Construction & Materials
- Made from class HGB 3 or better glass to ensure chemical resistance and prevent contamination.
- One-piece glass construction with strict controls on shape, wall thickness, and bore dimensions.
- Graduation lines and colour codes on Type I pipettes are durable and applied according to ISO 1769 guidelines.
Volumetric Performance
- Accuracy is defined as the closeness of the mean delivered volume to the nominal volume.
- Repeatability measures the consistency of individual volume deliveries.
- Testing involves weighing pipettes before and after filling with distilled water at a reference temperature of 20°C.
- Pipettes must meet manufacturer-defined limits for accuracy and repeatability using standardized test methods.
Markings and Colour Coding
- Packaging must display key information including reference temperature, nominal volume, manufacturer details, volumetric performance, batch number, and ISO standard reference.
- Colour coding follows ISO 1769 to facilitate easy identification of volume capacities.
- Type I pipettes have permanent black graduation lines, while Type II rely on package markings.
Applications
The ISO 7550 standard micropipettes are essential tools for:
- Biomedical Research – accurate transfer of microliter volumes in molecular biology and chemistry.
- Clinical Laboratories – disposable micropipettes reduce contamination risk during assays and diagnostics.
- Quality Control Laboratories – consistent volumetric measurements for analytical procedures.
- Educational Laboratories – training with standardized micropipettes ensures reproducibility and technique precision.
Using disposable, ISO-compliant micropipettes supports laboratory safety, minimizes cross-contamination, and improves measurement reliability for critical experiments and protocols.
Related Standards
- ISO 8417 – Volumetric instruments for accurate liquid measurement.
- ISO 1769 – Colour coding for pipettes to standardize capacity identification.
- ISO 719 – Glass hydrolytic resistance testing ensuring chemical durability of laboratory glassware.
- ISO 3534 – Statistical principles relevant for accuracy and repeatability assessments.
By aligning with these complementary ISO standards, laboratories ensure micropipettes meet global safety, quality, and performance requirements, facilitating international consistency in scientific workflows.
For laboratory professionals, quality managers, and manufacturers, adherence to ISO 7550:1985 ensures disposable micropipettes deliver precise, reliable volumes in a single-use format tailored for modern laboratory needs.
