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.
Biotin ameliorates muscle cramps of hemodialysis patients: a prospective trial.
Patients with renal failure undergoing hemodialysis often have muscle cramps during and after the dialysis therapy. Muscle cramps are defined as the sudden onset of a prolonged involuntary muscle contraction accompanied with severe pain, resulting in early termination of a HD session and inadequate dialysis. The etiology of the cramps is unknown and effective anti-cramp medicine is not available. We have hypothesized that water-soluble vitamins are deficient in HD patients. Accordingly, we administrated biotin to 14 patients who had frequent muscle cramps during HD sessions. Oral administration of 1 mg/day biotin promptly reduced the onset and the severity of cramps in 12 patients both during and after HD. Then, the plasma biotin levels were measured by an enzyme-linked immunosorbent assay method (ELISA) in HD patients, including 14 patients with cramps and 13 patients without cramps, and 11 healthy volunteers. Plasma biotin levels were elevated in 27 HD patients at baseline compared with healthy volunteers [451 (377 - 649) vs. 224 (148 - 308) ng/l, median (lower-upper quartiles); p < 0.0001]. Unexpectedly, among the 14 cramp patients, the biotin levels were significantly higher in biotin-ineffective 7 patients than biotin-effective 7 patients [1,064 (710 - 1,187) vs. 445 (359 - 476) ng/l; p < 0.001]. Thus, the biotins measured by ELISA may consist of not only intact biotin but also its metabolites that do not function as a vitamin. In conclusion, biotin administration is one choice to relieve HD patients from muscle cramps regardless of their elevated plasma biotin levels.
The biotin content of breakfast cereals
Determination, par une methode microbiologique utilisant Lactobacillus plantarum, de la teneur en biotine de 66 marques de cereales pour petit dejeuner. Les variations observees sont dues a l'espece de cereale, ainsi qu'aux autres constituants du melange