Abstract:

A method of high performance liquid chromatography-linear ion trap/orbitrap high-resolution mass spectrometry (HPLC-LTQ/Orbitrap MS) was used to screen and confirm banned azo colorants in textiles rapidly. The analytes were reduced to carcinogenic aromatic amines with sodium dithionite in citrate buffer solution. The reduced solution was extracted by diatomite, and loaded onto an Acquity UPLC BEH C18 column (50 mm×2.1 mm, 1.7 μm)with a gradient elution of methanol and 0.1%(v/v) methane acid aqueous solution, and finally detected by linear ion trap/orbitrap high-resolution mass spectrometry in positive ESI mode. In mass spectrometry method, the MS spectrum of high-resolution and the collision induced dissociation (CID) spectrum of data-dependent scan mode were used for screening analysis and conformation, respectively. The calibration curves showed a good linearity in the range of 0.05-2.00 mg/L, and the correlation coefficients (r) were higher than 0.99. By detecting spiked samples, the limits of quantification were 0.08 mg/kg for all the residues and the recoveries were in the range of 65.5%-111.5% with the relative standard deviations (RSDs) between 0.87% and 2.49%. The results indicate that the method is simple, rapid, sensitive and suitable for the qualitative and quantitative analysis of carcinogenic aromatic amines in textiles.

Key words: banned azo colorants, carcinogenic aromatic amines, high performance liquid chromatography-linear ion trap/orbitrap high-resolution mass spectrometry (HPLC-LTQ/Orbitrap MS), textiles