isotype control

https://doi.org/10.1351/goldbook.13348
Antibody exhibiting the non-specific characteristics of the antibody-isotype but lacking any specificity for the antigen in question; used as a negative control in antibody-antigen detection assays, notably in flow cytometry.
Source:
PAC, 2012, 84, 1113. (IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)) on page 1197 [Terms] [Paper]