Sun Diagnostics, LLC (New Gloucester, ME) strives to identify and develop unique products for the in vitro diagnostic (IVD) industry.

Sun Diagnostics simplifies interference testing with the ASSURANCE™ Interference Test Kit product line, including Test Kits for routine interferents (triglyceride-rich lipoproteins (lipemia), hemolysate, protein, conjugated and unconjugated bilirubin, HAMA, rheumatoid factor (RF), and common drugs. We are proud to introduce a new Assurance™ Biotin Interference Kit for assessing the impact of biotin on immunoassay interference.

Biotin binds to streptavidin with high affinity, making the biotin-streptavidin system useful for immunoassays. However, elevated concentrations of endogenous biotin can interfere with these immunoassays. In competitive assays, useful for small molecules and hormones such as thyroxine (T4), where the assay signal is inversely proportional to analyte concentration, biotin causes a falsely low signal and spuriously high result. In sandwich assays, like thyroid stimulating hormone (TSH), where the assay signal is proportional to analyte concentration, biotin interference causes a low signal and a falsely low result.

Older investigations of interference tested relatively low biotin concentrations of up to about 125 ng/mL and found no interference. Recently however, biotin nutritional supplements have been promoted for skin and hair benefits and for conditions such as diabetes and improvement of quality of life in multiple sclerosis. Individuals are taking supplemental biotin from about 20 mg/day to as much as 300 mg/day. Serum biotin concentrations up to 1200 ng/mL may be present in serum specimens collected from patients taking 300 mg biotin per day.

Assurance™ Biotin Interference Material is available in 1 mL aliquots at 20-fold the recommended test concentration of 1200 ng/mL (24,000 ng/mL). This concentration allows for use at a 1:20 dilution in the serum (or another matrix).