Ph. Eur. 2.2.29. Liquid Chromatography
Summary
Ph. Eur. 2.2.29 (Liquid Chromatography) defines LC principles, apparatus, and general procedural elements used by monographs for assay, identification, and related substances testing. It is applied with the specific conditions in each monograph. System-suitability definitions, default criteria, and allowed adjustments are provided in Ph. Eur. 2.2.46 (PDG-harmonized with USP <621>/JP).
Key Principles & Scope
Principle: Separation by differential distribution between a liquid mobile phase and solid stationary phase within a column; analytes elute at characteristic retention times enabling identification and quantification.
Apparatus: Pump, injector, column/stationary phase, detector (e.g., UV-Vis), and data system; exact configurations and conditions are set in the monograph. Instrument performance/SST expectations and terminology are standardised in 2.2.46.
System suitability & adjustments (see 2.2.46): Prior to analysis, verify performance according to 2.2.46 and any monograph-specific criteria. The harmonized chapter clarifies that retention times are informational, sets the default symmetry factor 0.8–1.8, defines the S/N baseline (20× peak width at half-height; ≥5× if needed), and specifies allowed adjustments (isocratic/gradient tolerances, column dimensions scaling, flow/injection changes), provided selectivity and elution order are maintained and SST passes.
How 2.2.29 is used
Cited broadly across Ph. Eur. monographs (e.g., assays, related substances, identification). The monograph sets the LC conditions; 2.2.46 supplies the harmonized SST/adjustment framework required for compliant execution.