Quality
Reference standards, system suitability and controls
The materials and checks that allow an analytical run to be interpreted with confidence.
A reference standard should be sufficiently characterised for its use. The required knowledge of identity, purity or content depends on whether…
02System suitabilitySystem-suitability tests check before or during a run that the complete system can produce acceptable data. Examples include repeatability, resolution, tailing…
03Blanks, positive and negative controlsA blank can reveal contamination or background, while positive and negative controls test whether the procedure distinguishes expected states. A failed…
Reference standards
A reference standard should be sufficiently characterised for its use. The required knowledge of identity, purity or content depends on whether it supports identification, quantitation or performance control. Origin and storage conditions should be documented.
System suitability
System-suitability tests check before or during a run that the complete system can produce acceptable data. Examples include repeatability, resolution, tailing or response. Criteria should have a scientific basis and be predefined.
Blanks, positive and negative controls
A blank can reveal contamination or background, while positive and negative controls test whether the procedure distinguishes expected states. A failed control is not fixed by selecting favourable results; it requires investigation and a documented decision on the run.
LABORATORY APPLICATION
Turning the principle into an auditable record
Maintain a standard register with origin, identity, opening date, storage, expiry or retest and stated use. In the analytical run, connect each standard and control to the criterion it checks. This allows the acceptance decision to be reconstructed later.
PRIMARY & OFFICIAL SOURCES
Sources and further reading
COMMON QUESTIONS
Questions specific to this topic
What does a reference standard do?
It provides a characterised comparison point for identity, quantitation or performance control, depending on use.
What is system suitability?
Prespecified checks that the complete setup can produce acceptable data in that run.
Why include a blank?
It helps detect background, contamination or carry-over not originating from the sample.