Serum Testosterone by Liquid Chromatography Tandem Mass Spectrometry for Routine Clinical Diagnostics

Author(s):  
Lennart J. van Winden ◽  
Olaf van Tellingen ◽  
Huub H. van Rossum
2008 ◽  
Vol 54 (8) ◽  
pp. 1290-1297 ◽  
Author(s):  
Linda M Thienpont ◽  
Katleen Van Uytfanghe ◽  
Stuart Blincko ◽  
Carol S Ramsay ◽  
Hui Xie ◽  
...  

Abstract Background: The recent interest of clinical laboratories in developing serum testosterone assays based on isotope dilution–liquid chromatography–tandem mass spectrometry (ID-LC-MS/MS) stems from the lack of accuracy of direct immunoassays. In this study, we assessed the accuracy and state of standardization (traceability) of 4 published ID-LC-MS/MS procedures in a method comparison with an ID–gas chromatography (GC)–MS reference measurement procedure listed in the database of the Joint Committee for Traceability in Laboratory Medicine. Methods: The study used 58 specimens from different patient categories. Each specimen was measured in triplicate (ID-LC-MS/MS) and quadruplicate (ID-GC-MS) in independent runs. Results: The testosterone concentrations by ID-GC-MS were 0.2–4.4 nmol/L (women), 0.2–2.0 nmol/L (hypogonadal man), and 10.1–31.3 nmol/L (normogonadal men). For ID-GC-MS, the CV was nearly constant, with a median of 1.0%; for ID-LC-MS/MS, it was concentration-dependent, with a median of up to 8%. Weighted Deming regression gave mean slopes, intercepts, and correlation coefficients of 0.90–1.11, −0.055–0.013 nmol/L, and 0.993–0.997, respectively. The % difference plot showed between 7% and 26% of the results outside a total error limit of 14%, with median deviations from ID-GC-MS between −9.6 and 0.4%. Conclusions: This study demonstrated fairly good accuracy and standardization of the tested ID-LC-MS/MS procedures. Performance differences between procedures were evident in some instances, due to improper calibration and between-run calibration control. This emphasizes the need for thorough validation, including traceability, of new ID-LC-MS/MS procedures.


2008 ◽  
Vol 54 (11) ◽  
pp. 1855-1863 ◽  
Author(s):  
Steve Shiraishi ◽  
Paul W N Lee ◽  
Andrew Leung ◽  
Victor H H Goh ◽  
Ronald S Swerdloff ◽  
...  

Abstract Background: Recent reports have described inherent problems with androgen immunoassays compared with mass spectrometry analyses. Methods: We developed a method for measuring serum testosterone (T) and 5α-dihydrotestosterone (DHT) simultaneously via liquid–liquid extraction followed by liquid chromatography–tandem mass spectrometry (LC-MS/MS) with positive-mode electrospray ionization. Results: The DHT and T calibrators showed a linear response from 0.069 nmol/L to 34.4 nmol/L and 69.3 nmol/L, respectively. T interference in the DHT assay and vice versa were negligible. Within- and between-run imprecision values were <5% for both analytes. Percent recoveries of T and DHT spiked into samples at concentrations spanning the calibration curve were 100%–113% and 98%–107%, respectively. The lower limit of quantification was 0.069 nmol/L for both steroids. Serum T concentrations measured by LC-MS/MS were different from those obtained by RIA, especially at lower T concentrations. Serum DHT concentrations measured by LC-MS/MS were markedly lower than those generated by RIA because of the nonselectivity of the RIA without chromatography. The reference intervals (mean ± 2 SDs) determined for T and DHT were 9.2–33.7 nmol/L and 0.47–2.65 nmol/L, respectively, for 113 healthy adult men and 0.33–2.02 nmol/L and 0.09–0.91 nmol/L, respectively, for 133 healthy premenopausal women. Conclusions: We have developed and validated a selective and precise method for simultaneous measurements of serum T and DHT that can be adopted for routine measurements of these androgens in health and disease in men and women.


Author(s):  
Faye B. Vicente ◽  
Frederick A. Smith ◽  
Rafael Sierra ◽  
Sihe Wang

AbstractLow levels of serum testosterone typically found in women and children cannot be reliably measured by immunoassay. We developed a simple and sensitive method using high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS). Sample preparation involved protein precipitation of serum (1.0mL) with acetonitrile containing the internal standard (testosterone-


Sign in / Sign up

Export Citation Format

Share Document