Title: titer
Long Title: IUPAC Gold Book - titer
DOI: 10.1351/goldbook.13745
Status: current

Definition
Reciprocal of the highest dilution of a titration of an antigen with an antibody that gives a measurable effect (e.g., agglutination), and thus an empirical measure of the avidity of an antibody.

Example
If the effect is seen until a dilution of \(\pu{1\!{:}\! 1000}\), the antibody titer is \(\pu{1000}\).

Source
- PAC, 2012, 84, 1113. 'IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)' on page 1254 (https://doi.org/10.1351/PAC-REC-11-06-03)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/13745/html
- json: https://goldbook.iupac.org/terms/view/13745/json
- xml: https://goldbook.iupac.org/terms/view/13745/xml

Citation: Citation: 'titer' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.13745
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Accessed: 2026-06-28T15:03:16+00:00