Determination of animal species origin of blood in artworks by LC-MS/MS

For art historians, understanding the animal origin of blood used in artworks is crucial for interpreting materials, techniques, and historical practices. It provides insight into the cultural, and religious significance of the work and allows for a more nuanced interpretation of its symbolic meaning. In this work, sets of peptides of blood proteins, more specifically their amino acid sequences, that are responsible for the differences between seven animal species (cat, cow, dog, goose, hen, human, and pig) were identified by LC-MS/MS. Protein materials used for the preparation of six model blood coatings were confirmed and the animal origin of the used blood was found. Finally, the blood origin in four samples taken from a set of Japanese and Chinese lacquer artworks from 18th and 19th century was also determined.