Scientific analysis of tie luo, a Qing Dynasty calligraphy artifact in the Palace Museum, Beijing, China

Heritage Science

Table 3 Analysis of the extracted components from the reddish pigments

RT (min)	Measured value (m/z)	Theoretical value (m/z)	Formula and compound	High energy fragment ions	Collision energy (eV)	MS/MS fragment ions
3.191	303.0866	303.0869	C₁₆H₁₆O₆ Protosappanin B	243.0229\213.0493\109.0250	20–40	270.0533\243.0548\231.0620\213.0493\185.0561\159.0414\109.0207
3.254	285.0701	285.0763	C₁₆H₁₄O₅ Brazilin	267.0331\243.0357\163.0434\121.0280	15–25	267.0598\243.0261\197.1108\163.0355\135.0415\121.0257
3.889	283.0579	283.0606	C₁₆H₁₂O₅ Brazilein	265.0424\241.0445\109.0250	20–40	265.0457\241.0350\240.0377\196.0456\173.0529\109.0207