Thienpont Linda M, Beastall Graham, Christofides Nicholas D, Faix James D, Ieiri Tamio, Jarrige Véronique, Miller W Greg, Miller Richard, Nelson Jerald C, Ronin Cathérine, Ross H Alec, Rottmann Michael, Thijssen Jos H, Toussaint Brigitte
Laboratory for Analytical Chemistry, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.
Clin Chem Lab Med. 2007;45(7):934-6. doi: 10.1515/CCLM.2007.155.
In the present paper the IFCC WG-STFT recommends and provides the rationale to establish metrological traceability of serum free thyroxine (FT4) measurements to a candidate international conventional reference measurement procedure. It is proposed that this procedure be based on equilibrium dialysis combined with determination of thyroxine in the dialysate with a trueness-based reference measurement procedure. The measurand is thus operationally defined as "thyroxine in the dialysate from equilibrium dialysis of serum prepared under defined conditions". With regard to the trueness-based reference measurement procedure, the WG-STFT recommends use of an isotope dilution-liquid chromatography/tandem mass spectrometry (ID-LC/tandem MS) procedure for total thyroxine that has been optimized towards measurement at picomolar concentration levels and that is listed in the database of the Joint Committee for Traceability in Laboratory Medicine (JCTLM). For calibration, the purified thyroxine material IRMM-468 (resulting from a project funded by the European Commission and recently submitted to the JCTLM) is proposed. The WG-STFT stresses that according to this recommendation it is a prerequisite to strictly adhere to the defined equilibrium dialysis procedure, whereas it is permissible to introduce variants in the ID-LC/tandem MS procedure.
在本论文中，国际临床化学与检验医学联合会（IFCC）的短期工作组（WG-STFT）推荐并给出了将血清游离甲状腺素（FT4）测量的计量溯源性建立至候选国际常规参考测量程序的基本原理。建议该程序基于平衡透析，并结合使用基于正确度的参考测量程序测定透析液中的甲状腺素。因此，被测量在操作上被定义为“在规定条件下制备的血清平衡透析所得透析液中的甲状腺素”。关于基于正确度的参考测量程序，WG-STFT建议使用一种针对皮摩尔浓度水平测量进行优化的总甲状腺素的同位素稀释-液相色谱/串联质谱（ID-LC/串联MS）程序，该程序列于实验室医学溯源联合委员会（JCTLM）的数据库中。对于校准，建议使用纯化的甲状腺素物质IRMM-468（这是一个由欧盟委员会资助的项目成果，最近已提交给JCTLM）。WG-STFT强调，根据该建议，严格遵守规定的平衡透析程序是一个先决条件，而在ID-LC/串联MS程序中引入变体是允许的。
