OPEN ACCESS pISSN 2234-3806
eISSN 2234-3814

Table. 7.

Table. 7.

Examples of LC-MS/MS assay components that require verification prior to assay execution with suggested verification materials and data components for possible review

Reagent(s) being changed/replaced Material(s) used for verification Data for acceptance
LC column SST Retention time, response, relative resolution (if known, isobars are included in SST solution)
Mobile phase replacement SST Retention time, response, relative resolution (if known, isobars are included in SST solution), response of analyte
LC hardware change (e.g., replacement tubing or pump seal) SST Retention time, response, relative resolution (if known, isobars are included in SST solution)
Autosampler wash solution High calibrator followed by blank Response of analyte in blank following high calibrator (or other carryover check)
Autosampler hardware change (e.g., new needle or rotor seal) High calibrator followed by blank and SST Response of analyte in blank following high calibrator (or other carryover check) Retention time and response of SST
LC preventive maintenance SST Retention time, response, relative resolution (if known, isobars are included in SST solution)
MS component replacement (e.g., electrode) SST Response
MS preventive maintenance SST Response
New IS solution Extracted blank with IS Response of analyte in extracted blank Expected response of IS (more important for SPE/LLE analyses)
New calibrators Calibrators, QCs, and patient samples. Previous PT’s or certified reference materials if available and within stability range Agreement between old and new calibrators.
Sample/QC results measured by old and new calibrators independently agree within expectations for assay
Certified reference or proficiency testing material demonstrates recovery within expected/allowed error.
New QCs Replicates of QCs Accuracy/trueness of results (if necessary)
CV (%) of QCs and established range
New assay material (e.g., new vendor of plates or pipette tips) Calibrators, QCs, blanks, and patient samples Response, accuracy, imprecision, interfering signals
Critical assay reagents (e.g., hydrolysis enzyme or precipitation solvent) Calibrators, QCs, blanks, and patient samples Response, accuracy, imprecision, interfering signals
Critical assay material (e.g., new lot of SPE media) Calibrators, QCs, blanks, and patient samples Response, accuracy, imprecision, interfering signals

Abbreviations: LC, liquid chromatography; SST, system suitability test; MS, mass spectrometer; PT, proficiency test; SPE, solid phase extraction; LLE, liquid-liquid extraction.

Ann Lab Med 2022;42:531~557 https://doi.org/10.3343/alm.2022.42.5.531

© Ann Lab Med