[Determination of N-[4- (4-aminobenzyl) -phenyl] acetamide hemoglobin adduct in blood by ultra performance liquid chromatography-tandem mass spectrometry]

Objective: To establish the method for the determination of N-Acetyl-4, 4'-diaminodiphenylmethane (AcMDA) adduct in the hemoglobin by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) . Methods: The 20 mg hemoglobin sample was weighed into a 15 ml centrifuge tube, adding 20 μg/L internal standard solution AcMDA-D8 10 μl, then hydrolyzed with 1 ml 0.1 mol/L sodium hydroxide solution at 37°C for 0.5 hours, extracted with dichloromethane and concentrated by vacuum concentrator. The residue was dissolved in acetonitrile and detected by UPLC-MS/MS, then quantitative by internal standard method. Results: The linearity of the method was good at the range of 0.05-25.00 μg/L with a correlation coefficient of 0.9996, the detection limit (LOD) and limit of quantitation (LOQ) were 0.07 and 0.2 ng/g Hb, respectively. The recovery rate was ranged from 91.0%-95.4%; the relative standard deviation (RSD) of intra-and inter-batch precision were 4.5%-6.3% and 3.7%-4.4%, respectively. Conclusion: The determination method meet the requirement of GBZ/T 210.5-2008.

[Determination of methylenedianiline in urine by high performance liquid chromatography-tandemmass spectrometry]

Objective: To develop a method for determination of metabolites of diphenylmethane diisocyanate (MDI) in urine, i.e. methylenedianiline (MDA) by high performance liquid chromatography-tandem mass (LC-MS-MS) . Methods: Urine samples were prepared by hydrolyzation with sulfuric acid and extraction by acetonitrile, and then separated on a Shim-pack XR-ODS column, analyzed with high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) . The external solvent standard calibration were tested. Results: The linearity ranges were 0.05~20.00 μg/L, The related coefficients were 0.999 5. The limit of detection was 0.02 μg/L. The rats of recovery were 91.0%~103.4%. The relative standard deviations were between 2.7%~7.3%. Conclusion: The method was sensitive, accurate and suitable for the MDA determination in urine of MDI exposed population.