Euromedlab: CONFIDENCE IN YOUR CALIBRATORS: ASSESSMENT OF MASSTRAK™ ENDOCRINE CALIBRATOR AND CONTROL SETS

Importance of the Topic

Routine measurement of steroid hormones is essential for clinical diagnostics and research into metabolic pathways governing sexual development, inflammation and cardiovascular regulation. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) has emerged as the preferred approach for steroid profiling due to its superior sensitivity, selectivity and capacity for multiplexed analysis. However, widespread adoption is hindered by the lack of harmonized calibrators and quality controls that ensure traceability and reproducibility across laboratories.

Objectives and Study Overview

This study aimed to evaluate the performance of the MassTrak Endocrine Steroid Calibrator and Quality Control Sets in a validated, in-house LC-MS/MS workflow. Specific goals included assessment of analytical sensitivity, linearity, precision, repeatability, accuracy and agreement with external quality assessment (EQA) samples across twelve clinically relevant steroid analytes.

Methodology

Serum samples (125 µL) were spiked with isotopically labeled internal standards, precipitated with methanol and water, then centrifuged. A fraction of supernatant underwent cleanup on an Oasis MAX µElution plate using sequential washes (1% formic acid in 10% acetonitrile; 1% ammonia in 10% acetonitrile). Analytes were eluted with 60% aqueous acetonitrile and neutralized with ammonium bicarbonate buffer to improve chromatographic peak shape for DHEAS.

Instrumentation Used

• Waters ACQUITY UPLC I-Class system
• Waters CORTECS C8 column (2.1 × 100 mm) with in-line frit
• Waters Xevo TQ-S micro triple quadrupole mass spectrometer
• Multiple Reaction Monitoring in positive and negative electrospray modes

Results and Discussion

Baseline chromatographic resolution was achieved for all twelve steroid hormones, including isomeric pairs. The lowest calibrator level demonstrated signal-to-noise ratios exceeding 10 PtP for each analyte. Calibration curves exhibited excellent linearity with mean correlation coefficients (r2) above 0.994. Precision and repeatability were evaluated over five days (n = 25) and yielded coefficients of variation ≤ 7.7%. Quality control accuracy across low, medium and high levels ranged from 91.0 to 112.4% of nominal values. Comparison with UK NEQAS EQA samples showed mean bias within ± 7.8% for key analytes such as testosterone, androstenedione, DHEAS, cortisol, 17-OHP and progesterone. These performance metrics demonstrate the reliability of MassTrak calibrators and controls in delivering traceable, standardized results.

Benefits and Practical Applications

• Metrological traceability supports compliance with ISO 15189 requirements for clinical laboratories.
• Lot-to-lot consistency enhances longitudinal method performance and comparability.
• Pre-manufactured calibrators and controls reduce hands-on time, labor and potential for preparation errors.
• Comprehensive analyte coverage simplifies multiplex steroid assays for endocrine panels.

Future Trends and Applications

Advances in high-throughput sample preparation and automation will further streamline steroid profiling. Integration of standardized calibrators with laboratory information management systems can enable real-time performance monitoring. Emerging mass spectrometry platforms with enhanced sensitivity may expand the dynamic range, enabling measurement of low-abundance steroids in neonatal screening or research applications. Harmonization of reference materials across global EQA programs will support wider adoption of mass spectrometry in routine clinical diagnostics.

Conclusion

The MassTrak Endocrine Steroid Calibrator and Quality Control Sets provide a robust, traceable solution for multiplex LC-MS/MS analysis of steroid hormones. Their excellent precision, accuracy and agreement with external standards deliver confidence in laboratory results while reducing resource burden associated with in-house preparation. Implementation of these IVD-labeled materials can support harmonized steroid measurements across clinical and research settings.

References

Hammond G, Calton L, Foley D, Breen N, Rossiter P, Bosch G, Donzelli S. Confidence in Your Calibrators: Assessment of MassTrak Endocrine Calibrator and Control Sets. Waters Corporation; 2022.