A multicenter comparison of whole blood vitamin B6 assays

2016 ◽  
Vol 54 (4) ◽  
Author(s):  
Bertrand D. van Zelst ◽  
Roseri J.A.C. Roelofsen de Beer ◽  
Marjolein Neele ◽  
Snježana Kos ◽  
Ido P. Kema ◽  
...  
Keyword(s):  
Pilot Study ◽  
Whole Blood ◽  
Analytical Methods ◽  
Vitamin B6 ◽  
Method Comparison ◽  
Reference Method ◽  
Hplc Method ◽  
Blood Samples ◽  
Whole Blood Samples ◽  
Suitable Reference

AbstractThe aim of this study was to compare different analytical methods that are currently in use in the Netherlands for the measurement of whole blood vitamin B6.This method comparison study consisted of two separate parts. (1) Four laboratories participated in a pilot study in which the commercial Chromsystems and INstruchemie method, and a laboratory developed liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and HPLC method were compared. Sixty-nine frozen whole blood samples and six lyophilized whole blood samples were used for comparison. (2) In the nationwide part of the study, 49 laboratories participated in the analysis of three identical sets of two whole blood samples of which one set was freshly analyzed, one set was analyzed after storage at −20 °C and one set was analyzed after lyophilization.In both parts of the study, the HPLC and LC-MS/MS methods showed equivalent results for all sample types tested. The Chromsystems method showed a positive bias of 45% (pilot study) and 30% (nationwide study) towards the LC-MS/MS method when fresh or frozen samples were used. The measurement of lyophilized samples showed no differences between the methods. The results of the INstruchemie method were inconclusive due to the low number of participants.The different analytical methods for measuring vitamin B6 produce different results when whole blood patient samples are measured. The recognition of a reference method or the development of suitable reference materials and quality control materials might serve as a first step towards improved standardization or harmonization of the whole blood vitamin B6 assay.

Analytical Performance of EMITTM Cyclosporine Assay Evaluated

1991 ◽  
Vol 37 (12) ◽  
pp. 2130-2133 ◽  
Author(s):  
Amitava Dasgupta ◽  
Sylvia Saldana ◽  
Manju Desai
Keyword(s):  
Whole Blood ◽  
Hplc Method ◽  
Palo Alto ◽  
Blood Samples ◽  
Transplant Patients ◽  
Analytical Recovery ◽  
Liver And Kidney ◽  
Kidney Transplant Patients ◽  
Whole Blood Samples ◽  
High Control

Abstract We evaluated the EMITTM Cyclosporine Assay (Syva Co., Palo Alto, CA), using the Cobas-Mira analyzer to assess the precision, accuracy, and analytical recovery from whole-blood samples supplemented with cyclosporine. We also performed comparative analysis of whole-blood samples containing cyclosporine from liver and kidney transplant patients by using EMIT, HPLC, and RIA (IncStar Cyclo-Trac, SP assay). Before assay by EMIT or RIA, cyclosporine was extracted from whole blood with methanol. For the HPLC method, whole blood containing cyclosporine was hemolyzed with 300 mL/L acetonitrile in water; cyclosporine was extracted from the hemolysate with acetonitrile. The within-run and between-run CVs for the EMIT assay of cyclospoprine were 9.9% (means = 72.6, SD = 7.2 μg/L; n = 20) and 13.5% (means = 75.0, SD = 10.1 μg/L; n = 26) for the low control; 3.5% (means = 194.7, SD = 6.8 μg/L; n = 20) and 8.1% (means = 189.0, SD = 15.3 μg/L; n = 26) for the medium control; and 7.0% (means = 332.5, SD = 23.3 μg/L; n = 20) and 7.1% (means = 340.0, SD = 24.2 μg/L; n = 24) for the high control (Bio-Rad, whole-blood controls). Analytical recovery of cyclosporine from drug-supplemented samples averaged 99% for EMIT, 104% for HPLC, and 90% for RIA over a concentration range of 50-500 μg/L. Analysis of 196 specimens by HPLC (x) vs EMIT (y) gave the following regression statistics: y = 1.27x + 16.44; IncStar‘s RIA (x‘) vs EMIT: y = 1.12x‘ - 2.50; HPLC vs RIA: x‘ = 1.10x + 23.87.

Standardization of glycohemoglobin results and reference values in whole blood studied in 103 laboratories using 20 methods

1995 ◽  
Vol 41 (1) ◽  
pp. 82-86 ◽  
Author(s):  
C W Weykamp ◽  
T J Penders ◽  
K Miedema ◽  
F A Muskiet ◽  
W van der Slik
Keyword(s):  
Reference Values ◽  
Analytical Method ◽  
Whole Blood ◽  
Reference Method ◽  
Diabetes Control ◽  
Blood Samples ◽  
Interpretation Criteria ◽  
Whole Blood Samples

Abstract We investigated the effect of calibration with lyophilized calibrators on whole-blood glycohemoglobin (glyHb) results. One hundred three laboratories, using 20 different methods, determined glyHb in two lyophilized calibrators and two whole-blood samples. For whole-blood samples with low (5%) and high (9%) glyHb percentages, respectively, calibration decreased overall interlaboratory variation (CV) from 16% to 9% and from 11% to 6% and decreased intermethod variation from 14% to 6% and from 12% to 5%. Forty-seven laboratories, using 14 different methods, determined mean glyHb percentages in self-selected groups of 10 nondiabetic volunteers each. With calibration their overall mean (2SD) was 5.0% (0.5%), very close to the 5.0% (0.3%) derived from the reference method used in the Diabetes Control and Complications Trial. In both experiments the Abbott IMx and Vision showed deviating results. We conclude that, irrespective of the analytical method used, calibration enables standardization of glyHb results, reference values, and interpretation criteria.

Steadiness/stability of antiepileptic drugs in serum, plasma and whole-blood samples under various storage methods

2010 ◽  
Vol 41 (02) ◽  
Author(s):  
N Shazi ◽  
A Böss ◽  
HJ Merkel ◽  
F Scharbert ◽  
D Hannak ◽  
...  
Keyword(s):  
Antiepileptic Drugs ◽  
Whole Blood ◽  
Blood Samples ◽  
Storage Methods ◽  
Whole Blood Samples

scholarly journals Determination of 19 Psychoactive Substances in Premortem and Postmortem Whole Blood Samples Using Ultra-High-Performance Liquid Chromatography–Tandem Mass Spectrometry

Separations ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 78
Author(s):  
Sevasti Karampela ◽  
Jessica Smith ◽  
Irene Panderi
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Formic Acid ◽  
Whole Blood ◽  
High Performance ◽  
Tandem Mass ◽  
Psychoactive Substances ◽  
Blood Samples ◽  
Whole Blood Samples

An ever-increasing need exists within the forensic laboratories to develop analytical processes for the qualitative and quantitative determination of a broad spectrum of new psychoactive substances. Phenylethylamine derivatives are among the major classes of psychoactive substances available on the global market and include both amphetamine analogues and synthetic cathinones. In this work, an ultra-high-performance liquid chromatography-positive ion electrospray ionization tandem mass spectrometric method (UHPLC-ESI-MS/MS) has been developed and fully validated for the determination of 19 psychoactive substances, including nine amphetamine-type stimulants and 10 synthetic cathinone derivatives, in premortem and postmortem whole blood. The assay was based on the use of 1 mL premortem or postmortem whole blood, following solid phase extraction prior to the analysis. The separation was achieved on a Poroshell 120 EC-C18 analytical column with a gradient mobile phase of 0.1% formic acid in acetonitrile and 0.1% formic acid in water in 9 min. The dynamic multiple reaction monitoring used in this work allowed for limit of detection (LOD) and lower limit of quantitation (LOQ) values of 0.5 and 2 ng mL−1, respectively, for all analytes both in premortem and postmortem whole blood samples. A quadratic calibration model was used for the 12 quantitative analytes over the concentration range of 20–2000 ng mL−1, and the method was shown to be precise and accurate both in premortem and postmortem whole blood. The method was applied to the analysis of real cases and proved to be a valuable tool in forensic and clinical toxicology.

scholarly journals Isolation and characterization of circulating pro-vascular progenitor cell subsets from human whole blood samples

2021 ◽  
Vol 2 (1) ◽  
pp. 100311
Author(s):  
Daniella C. Terenzi ◽  
Ehab Bakbak ◽  
Justin Z. Trac ◽  
Mohammad Al-Omran ◽  
Adrian Quan ◽  
...  
Keyword(s):  
Whole Blood ◽  
Progenitor Cell ◽  
Blood Samples ◽  
Human Whole Blood ◽  
Isolation And Characterization ◽  
Whole Blood Samples
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