Comprehensive assessment of biotin interference in immunoassays

Background. Biotinylated antibodies and analogues are currently used in many immunoassays while biotin is widely used as a dietary supplement. Thus, biotin interference is an emerging issue for clinical laboratories. Methods: Various concentrations of biotin solutions were prepared using pooled patient serum samples. All analytes were measured by sandwich or competitive immunoassay on the Roche Cobas 8000 e602 platform. Results: Some of the sandwich immunoassay results were falsely decreased to different extents by different biotin levels, while some of the competitive immunoassay results were falsely increased. The most notable false reductions were in high-sensitivity troponin T, thyroid-stimulating hormone, and follicle-stimulating hormone results, while the most notable false increases were in triiodothyronine and vitamin D results. Other immunoassay results were also affected to some extent by biotin interference. Conclusions: Biotin can interfere in immunoassays and result in aberrant test results. Clinicians should use caution in interpreting abnormal results in patients who ingest biotin.