Simultaneous detection of a wide range of synthetic and natural dyes in artworks using UHPLC-PDA-HRMS.

This paper presents a validated method using ultra-high pressure liquid chromatography with photodiode array detection coupled to high-resolution mass spectrometry (UHPLC-PDA-HRMS) for the simultaneous analysis of a wide range of natural and synthetic organic colourants, including neutral, acidic and basic dyes. In total, 30 natural and 62 synthetic organic dye reference samples (which contain 118 compounds because some of the dyes are composed of mixtures) were analysed. The method demonstrated good linearity for the 12 dyes selected for method validation achieving correlation coefficients (R) exceeding 0.

Characterization of Dye Extracts from Historical Cultural-Heritage Objects Using State-of-the-Art Comprehensive Two-Dimensional Liquid Chromatography and Mass Spectrometry with Active Modulation and Optimized Shifting Gradients.

Unbiased characterization of dyes and their degradation products in cultural-heritage objects requires an analytical method which provides universal separation power regardless of dye classes. Dyes are small molecules that vary widely in chemical structure and properties, which renders their characterization by a single method challenging. We have developed a comprehensive two-dimensional liquid chromatography method hyphenated with mass spectrometry and UV-vis detection.