Understanding and managing biotin interference in immunoassays

Screening for interference in immunoassays.

Screening for interference in immunoassays.

BACKGROUND The presence of interfering substances in patient samples submitted for immunoassay cannot be reliably anticipated. We therefore evaluated three interference screening techniques and estimated the prevalence of interfering substances as defined by positive outcomes with these protocols. METHODS We evaluated 160 samples for the presence of substances that may interfere with four imm...

Metabolite and matrix interference in phenytoin immunoassays.

The major phenytoin metabolite, 5-(p-hydroxyphenyl)-5-phenylhydantoin glucuronide (HPPG), was primarily responsible for the positive bias noted when uremic specimens were assayed with the Abbott TDx Free Phenytoin fluorescence polarization immunoassay. The amount of bias depended on both HPPG and phenytoin concentration, increasing with increases in either concentration. The new Abbott TDx II a...

Interference in immunoassays: avoiding erroneous results

types of immunoassay interference are similar to interferences in other chemistry assays and some types are unique to immunoassays. The interfering substance (interferent) in the sample may be exogenous to the patient, for example a drug, or endogenous, for example antibodies produced by the patient. The bias caused by interference may be positive or negative and, in some cases, the degree and ...

False biochemical diagnosis of hyperthyroidism in streptavidin-biotin-based immunoassays: the problem of biotin intake and related interferences.

Immunoassays are now commonly used for hormone measurement, in high throughput analytical platforms. Immunoassays are generally robust to interference. However, endogenous analytical error may occur in some patients; this may be encountered in biotin supplementation or in the presence of anti-streptavidin antibody, in immunoassays involving streptavidin-biotin interaction. In these cases, the i...