- (DNA) A fragment of known size used as reference for analytical purposes.
- (genetic) A gene with known phenotype and mapped position.
- (chromatography) A reference substance co-chromatographed with the sample to assist in identifying the components.
Orange Book, 2nd ed., p. 97 (https://media.iupac.org/publications/analytical_compendium/)
PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 159 (https://doi.org/10.1351/pac199264010143)
PAC, 1993, 65, 819. 'Nomenclature for chromatography (IUPAC Recommendations 1993)' on page 837 (https://doi.org/10.1351/pac199365040819)