A simple and rapid ultra-high-performance liquid chromatography-tandem mass spectrometry method to determine plasma biotin in hemodialysis patients.
A simple, rapid, and selective method for determination of plasma biotin was developed using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). After single-step protein precipitation with methanol, biotin and stable isotope-labeled biotin as an internal standard (IS) were chromatographed on a pentafluorophenyl stationary-phase column (2.1 × 100 mm, 2.7 μm) under isocratic conditions using 10 mm ammonium formate-acetonitrile (93:7, v/v) at a flow rate of 0.6 mL/min. The total chromatographic runtime was 5 min for each injection. Detection was performed in a positive electrospray ionization mode by monitoring selected ion transitions at m/z 245.1/227.0 and 249.1/231.0 for biotin and the IS, respectively. The calibration curve was linear in the range of 0.05-2 ng/mL using 300 μL of plasma. The intra- and inter-day precisions were all <7.1%. The accuracy varied from -0.7 to 8.2%. The developed UHPLC-MS/MS method was successfully applied to determine plasma biotin concentrations in hemodialysis patients. Copyright © 2016 John Wiley & Sons, Ltd.
Quantification of biotin in plasma samples by column switching liquid chromatography – tandem mass spectrometry
Abstract Biotin (or Vitamin B7) is a vitamin where deficiency can be caused by inadequate intake. Biotin deficiency is rare, as most people get enough biotin from diet, since many foods contain biotin. In addition to biotin from food, intestinal bacteria can synthesize biotin, which can then be absorbed by the body. Supplementation with biotin has been advocated, mainly due to proposed beneficial effects on skin, nail and hair growth. There is no evidence that high biotin intakes are toxic, but a high intake may interfere with diagnostic assays that use biotin-streptavidin technology. These tests are commonly used to measure plasma concentrations of a wide range of hormones. Erroneous results may lead to misdiagnosis of various endocrine disorders. Supplementation with high-dose biotin has been used experimental for the treatment of diseases (e.g. multiple sclerosis) and high doses are used to obtain effect on nail and hair growth. On this background a demand for tests to determine if there is a risk of obtaining false test results when using biotin-streptavidin based tests have appeared. In this paper we present a method based on column switching liquid chromatography tandem mass spectrometry for the quantification of biotin in plasma and serum and explore the effects of biotin on an immunoassay based on biotin strept(avidin) chemistry.
Lipoic acid (thioctic acid) analogs, tryptophan analogs, and urea do not interfere with the assay of biotin and biotin metabolites by high-performance liquid chromatography/avidin-binding assay☆
Abstract Lipoic acid, urea, and tryptophan show structural similarities to the vitamin biotin. If these compounds can successfully compete with biotin or a biotinylated protein for binding to avidin, their presence in serum and urine would cause artifacts in avidin-binding assays for biotin. We assessed the ability of lipoic acid and certain analogs, urea, and l -tryptophan and tryptophan derivatives to interfere with the measurement of 16 biotin analogs by a high-performance liquid chromatography (HPLC)/avidin-binding assay. In this assay, compounds are separated by reversed-phase HPLC, followed by assay of each fraction based on binding to avidin-horseradish peroxidase. At physiologic concentrations, neither lipoic acid analogs (d-lipoate, l-lipoate, d,l-lipoamide, bisnorlipoate, β-hydroxybisnorlipoate, and tetranorlipoate) nor tryptophan derivatives exhibited detectable avidin-binding. Minor avidin-binding was seen for urea and l -tryptophan; binding ratios relative to biotin were 1 × 10−9 and 3 × 10−6, respectively. Urea did not co-elute on HPLC with any of the 16 biotin analogs, but l -tryptophan did co-elute with bisnorbiotin methyl ketone. However, because the relative avidin affinity of l -tryptophan is five orders of magnitude smaller than that of bisnorbiotin methyl ketone, we conclude that none of the tested compounds are likely to interfere with the measurement of biotin or its metabolites by an HPLC/avidin-binding assay.