Implementation of liquid chromatography/mass spectrometry into the clinical laboratory

BackgroundFor certain clinical chemistry and toxicology analytes, liquid chromatography (LC) coupled with tandem mass spectrometry (MS/MS) offers significant advantages over traditional testing by immunoassay.MethodsPublished reports comparing the performance of immunoassays against LC–MS/MS were reviewed. The tested analytes include testosterone, estradiol, thyroid hormones, vitamin D, immunosuppressants, steroids for newborn screening programs, and clinical and forensic toxicology.ResultsWhile immunoassays are widely used in the clinical laboratory, the analytical sensitivity and specificity are inferior for many of the analytes tested in routine clinical laboratories. Moreover, LC–MS/MS can be multiplexed for high testing throughput and multiple analyte detection. The disadvantages of LC-MS/MS include the absence of Food and Drug Administration (FDA) and Conformité Européenne (CE) Mark approved tests, the high cost of analytical instrumentation, and the technical expertise needed to operate and maintain analyzers.ConclusionsThe implementation of LC–MS/MS will increase in the next few years as this technology continues to improve and the advantages become more well known.

► Immunoassays are widely used in clinical practice but suffer from methodologic problems.
► LC-MS/MS is an emerging analytical technology for various clinical applications.
► Improved analytical sensitivity and specificity over immunoassays are attributes of LC-MS/MS.