Abstract:

A comprehensive analytical method based on ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-MS/MS) has been developed for the simultaneous determination of 33 primary aromatic amines (PAAs) in fine pigments such as gouache paint, oil painting pigment and acrylic paint. The primary aromatic amines in samples were extracted with acetonitrile. Then the extract was concentrated by centrifugation and nitrogen blow, finally diluted to 2 mL with methanol-water (1:9, v/v) and filtered through 0.22 μm membrane before UPLC-MS/MS analysis. The analytes were separated on a BEH Phenyl column (100 mm×2.1 mm, 1.7 μm) with 0.07% (v/v) formic acid in methanol-water as mobile phases in gradient elution. The PAAs were detected by UPLC-MS/MS under multiple reaction monitoring (MRM) mode and quantified by the internal standard method. The separation conditions, fragment voltages and collision energies were optimized. The impacts of extraction times, extraction solvents and concentration methods on recoveries were studied. The limits of detection and limits of quantitation for the 33 primary aromatic amines were 5-50 μg/kg and 15-150 μg/kg respectively. The mean recoveries of three different dye products at three spiked levels were 70.1%-115.8%. The relative standard deviations were 2.1%-15%. The experimental results indicated that the method is simple, rapid, sensitive, accurate and can meet the requirements for the determination.

Key words: fine pigments, primary aromatic amines (PAAs), ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-MS/MS)