A 3-min UPLC-MS/MS method for the simultaneous determination of plasma catecholamines and their metabolites: Method verification and diagnostic efficiency

OBJECTIVE: To verify a rapid and sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the quantification of catecholamines and their metabolites, and to validate its efficiency for the diagnosis of phaeochromocytomas and paragangliomas (PPGLs). METHODS: Plasma samples were pretreated with solid-phase extraction, followed by a 3-min UPLC-MS/MS analysis to quantify epinephrine (E), norepinephrine (NE), dopamine (DA), metanephrine (MN), normetanephrine (NMN) and 3-methoxytyramine (3-MT), simultaneously. The UPLC-MS/MS method was comprehensively verified and its diagnostic efficiency on PPGLs was tested using 7 PPGLs and 408 non-PPGLs patient plasma samples. RESULTS: Using the developed method, the limit of detections (LODs) of the 6 analytes ranged from 0.0002 nmol/L (MN) to 0.0250 nmol/L (NE), while the lower limit of measuring intervals (LLMIs) ranged from 0.05 nmol/L (E, MN and NMN) to 0.10 nmol/L (NE and DA). The reportable ranges were 0.05-30.00 nmol/L for E, MN and NMN, 0.10-30.00 nmol/L for NE and DA, 1.00-300.00 pg/mL for 3-MT. No significant matrix effect was detected after correcting using internal standard. Besides, intra-day and inter-day precision were also within acceptance criteria with coefficient of variations (CVs) ≤ 15% and recoveries ranged from 95% to 115% for all the 6 analytes. The carryover effect was lower than 10%. Its diagnostic efficiency for PPGLs was significantly increased, the areas under the receiver operating characteristic (ROC) curves were increased from 68.7% to 89.1% (using E, NE and DA) to 75.2%-99.9% (using MN, NMN and 3-MT). CONCLUSION: This study verified a rapid UPLC-MS/MS method for the determination of catecholamines and their metabolites in human plasma. It showed high diagnostic efficiency and will serve as an important tool to avoid the risk for missing patients with PPGLs.