Development and validation of a 34-analyte urine quantitative LC-MS/MS toxicology panel

Expeditious and accurate drug testing of urine specimens supports clinical operations ranging from pain management to emergency medicine. Tandem mass spectrometry when used in conjunction with chromatography (LC-MS/MS) is a highly specific and sensitive technique that can simultaneously quantify numerous analytes of interest, providing notable advantages in sensitivity and specificity over other technologies such as immunoassays. We describe the development and validation of a clinical LC-MS/MS toxicology panel for quantitation of 34 drugs and metabolites that combines two predecessor methods, simplifying our workflow and adding several analytes not previously detected in either method. Validation work encompassed an alternative matrix mixing study and characterization of potential matrix effects as well as determination of analytical measurement range, analytical sensitivity, analytical specificity, carryover, precision, stability, accuracy, and hydrolysis efficiency. Limits of quantitation achieved ranged from 1 to 25 ng/mL at the lower end and 2000 to 5000 ng/mL at the upper end.