Test Catalog

Test Id : BIOTN

Biotin, Serum

Useful For
Suggests clinical disorders or settings where the test may be helpful

Measurement of biotin in serum


Assessment of biotin concentrations in individuals taking biotin supplements


Investigation of unexpected results from immunoassays that utilize biotin-streptavidin detection methods


This test is not useful as a screen for biotinidase deficiency.


Serum biotin is usually at relatively low endogenous concentrations but can be found at high concentrations if vitamin and herbal supplements containing biotin are taken.


This test measures free biotin concentrations in serum and can be used to determine if a patient's high biotin concentrations are likely from biotin supplementation or treatment.

Method Name
A short description of the method used to perform the test

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) Stable Isotope Dilution Analysis

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Biotin, S

Lists additional common names for a test, as an aid in searching

Vitamin B7

Vitamin H

Specimen Type
Describes the specimen type validated for testing


Ordering Guidance

If testing for biotinidase deficiency is requested, order BIOTS / Biotinidase, Serum.

Shipping Instructions

Freeze specimens within 3 days of collection and send frozen.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Collection Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

0.5 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis  OK
Gross lipemia  OK
Gross icterus  OK

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Serum Frozen (preferred) 30 days
Refrigerated 7 days
Ambient 24 hours

Useful For
Suggests clinical disorders or settings where the test may be helpful

Measurement of biotin in serum


Assessment of biotin concentrations in individuals taking biotin supplements


Investigation of unexpected results from immunoassays that utilize biotin-streptavidin detection methods


This test is not useful as a screen for biotinidase deficiency.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Biotin is a water soluble B complex vitamin (vitamin B7 or vitamin H) that is an essential cofactor for the synthesis of fatty acids, catabolism of branched chained amino acids, and for gluconeogenesis. It is usually found at relatively low endogenous concentrations in patients on a normal diet. However, biotin can be found in over-the-counter multi-vitamins, prenatal vitamins, and dietary supplements marketed for hair, skin, and nail growth. Additionally, treatment of certain progressive multiple sclerosis patients with high doses of biotin has been reported to be beneficial. Biotin supplementation from either over-the-counter or prescription sources can result in extremely elevated circulating biotin. Some immunoassays in the clinical laboratory use chemistry that utilizes the high affinity and avidity that biotin has for binding avidin (or streptavidin). As a result, high serum biotin concentrations can yield inaccurate laboratory results in laboratory assays that utilize this biotin-streptavidin chemistry. Specifically, specimens with high biotin can yield falsely decreased results when the testing methodology utilizes sandwich-based methods or falsely increased results when the methodology utilizes competitive binding methods. Each clinical laboratory method that utilizes biotin-streptavidin chemistry has a defined biotin concentration limit above which serum biotin can interfere with assay results. This test measures free biotin concentrations in serum and can be used to determine whether a patient has high biotin concentrations that are likely from biotin supplementation/treatment.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

> or =18 years: < or =0.3 ng/mL

Reference values have not been established for patients who are <18 years of age.

Provides information to assist in interpretation of the test results

Biotin results that are significantly higher than the reference interval indicate biotin supplementation.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

It is unknown how long biotin will remain elevated in patients taking biotin supplements. Variables include the dose taken, the duration of supplementation, and the time of blood draw after ingestion.

Supportive Data

An internal study of volunteers taking 1 dose of 5,000 to 20,000 micrograms of biotin showed elevated serum biotin concentrations of between 10 to 50 ng/mL at 1 to 2 hours post supplementation.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Elston MS, Sehgal S, Du Toit S, Yarndley T, Conaglen JV: Factitious Graves’ disease due to biotin immunoassay interference-a case and review of the literature. J Clin Endocrinol Metab. 2016 Sep;101(9):3251-3255

2. Grimsey P, Frey N, Bendig G, et al: Population pharmacokinetics of exogenous biotin and the relationship between biotin serum levels and in vitro immunoassay interference. Int J Pharmacokinet. 2017 Sep 14;2:247-256

3. Katzman BM, Lueke AJ, Donato LJ, Jaffe AS, Baumann NA: Prevalence of biotin supplement usage in outpatients and plasma biotin concentrations in patients presenting to the emergency department. Clin Biochem. 2018 Sep;60:11-16

Method Description
Describes how the test is performed and provides a method-specific reference

Biotin (Vitamin B7) is quantified in serum by liquid chromatography-tandem mass spectrometry (LC-MS/MS).(Unpublished Mayo method)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.


Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

2 to 7 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

7 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

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  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their account representative. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.


LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
BIOTN Biotin, S 1980-2
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
606867 Biotin, S 1980-2

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports