[Determination of amanita peptide toxins in human urine by TurboFlow online clean-up-liquid chromatography-tandem mass spectrometry].

ABSTRACT

Amanita peptide toxins are cyclic polypeptide mushroom toxins that can cause acute liver damage. The fatality rate associated with these toxins is very high. Monitoring the concentration of amanita peptide toxins in human urine can provide valuable information for early clinical diagnosis and treatment. Therefore, a TurboFlow online clean-up-liquid chromatography-triple quadrupole mass spectrometry (TF-LC-MS/MS) method was established for the simultaneous quantitative determination of five amanita peptide toxins (α-amanitin, ß-amanitin, γ-amanitin, phallacidin, and phalloidin) in human urine. After pre-treatment with high-speed centrifugation, urine samples were analyzed using TF-LC-MS/MS. The main factors influencing purification efficiency, including the TF column, loading solution, eluting solution, transfer flow, and transfer time, were optimized in this study. Under the optimized experimental conditions, the analytes were purified using a TurboFlowTM Cyclone column (50 mm×0.5 mm) and separated on a Hypersil GOLD C18 column (100 mm×2.1 mm) using the mobile phases of methanol and 4 mmol/L aqueous ammonium acetate solution with gradient elution. The analytes were detected in selected reaction monitoring (SRM) mode via positive electrospray ionization. Matrix-matched external standard calibration was used for quantitation. The linear range of the method ranged from 1.0 µg/L to 50.0 µg/L for all five amanita peptide toxins, with correlation coefficients (r2) higher than 0.997. The limits of detection were 0.15-0.3 µg/L and the limits of quantification (LOQs) were 0.5-1.0 µg/L for the five amanita peptide toxins in urine. The intra-day and inter-day recoveries of amanita peptide toxins were 87.0%-108.6% and 86.8%-112.7%, respectively, at the spiked levels of 2.0, 5.0, and 10.0 µg/L. The intra-day and inter-day relative standard deviations (RSDs) were less than 14.5%. The method is accurate, rapid, sensitive, easy to operate, and can satisfy the requirements of public health emergency testing or clinical poisoning testing.