Accuracy
Closeness of agreement between a measured result and a value regarded as true or used as a reference. Accuracy is a qualitative concept and is not another word for precision.
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Terms that unlock the method.
A compact working vocabulary. Definitions are written for orientation and link back to formal terminology when exact metrological language matters.
Analyte
The chemical species or component being measured or characterized.
Background electrolyte
The conducting solution that fills an electrophoretic separation system and establishes chemical conditions such as pH and ionic strength.
Band broadening
The spreading of a sample zone as it travels through a separation system, reducing the ability to distinguish neighboring components.
Chromatogram
A record of detector response or another measured quantity against elution time, volume, or distance in chromatography.
Electropherogram
A record of detector response or another measured quantity against migration time or distance in an electrophoretic separation.
Electrophoretic mobility
The velocity of a charged species per unit electric field under stated medium conditions.
Electroosmotic flow
Bulk liquid movement caused by an electric field acting at a charged liquid–solid interface; its direction and magnitude depend on the surface, electrolyte, and field.
Efficiency
A description of band dispersion, commonly expressed through plate-based quantities; it is not the same as resolution.
Hold-up time
The time required for an unretained mobile-phase component to pass from injection to detection in a chromatographic system.
Limit of detection
The smallest signal or analyte quantity that can be declared detected using a stated decision rule and probabilities of error. It is specific to the complete measurement procedure and conditions.
Limit of quantification
The lowest analyte level that can be quantified with performance acceptable for the intended use; it should not be treated as another name for the detection limit.
Matrix effect
A change in analytical response caused by other sample components, including effects on recovery, separation, or detection.
Measurement uncertainty
A non-negative parameter describing the dispersion of values that could reasonably be attributed to the measurand using the available information. It is not the same thing as measurement error.
Migration time
The time required for a component to travel from introduction to detection in an electrophoretic system.
Mobile phase
The fluid that moves through a chromatographic system and carries sample components past the stationary phase.
Precision
Closeness of agreement among repeated measured values under stated conditions, commonly summarized by a standard deviation or related quantity. Precision alone does not establish accuracy.
Recovery
The fraction or percentage of an analyte carried through specified sampling or preparation steps and measured under stated conditions.
Repeatability
Measurement precision under a defined set of closely matched conditions, such as the same procedure, system, location, and short time interval.
Reproducibility
Measurement precision under stated conditions that deliberately differ, such as laboratory, operator, instrument, or time. The changed conditions must be identified.
Resolution
A measure of how distinctly two neighboring peaks or zones are separated, combining spacing and peak width.
Retention time
The elapsed time between sample introduction and the recorded maximum or reference point of a retained component.
Selectivity
In analysis, the extent to which other substances interfere with determining the target using a stated procedure. The word needs context when used quantitatively.
Sensitivity
The change in measured response per change in analyte quantity under stated conditions, often represented by a calibration slope. It is not a synonym for a low detection limit.
Separation factor
In column chromatography, the ratio of adjusted retention quantities for two peaks, conventionally written so it exceeds one. It is sometimes called chromatographic selectivity, but the less ambiguous term is separation factor.
Stationary phase
The phase fixed in place in a chromatographic system and involved in differential retention.
System suitability
Checks that an analytical system meets predefined performance criteria before or during intended use.
Test portion
The amount of material taken from a test sample for one measurement procedure.
Formal terminology: IUPAC Gold Book and IUPAC metrological and quality concepts. AI-assisted technical revision; human scientific review is required before production publication.