Table 1. Theoretical and measured masses of PD-gal and DD-gal from mass spectrometry analysis

	PD-gal	DD-gal
Theoretical mass1)	289.28 (= 104.15 + 180.156 − 18.015 + 22.989)	359.41 (= 174.28 + 180.156 − 18.015 + 22.989)
Measured mass2)	289.1261	359.2046
Molecular formula3)	C11H22O7Na	C16H32O7Na

The molecular weights of PD and DD are 104.15 and 174.28, respectively. Galactose and water are 180.15 and 18.018, respectively.
Mass spectrometry analysis measured these values (Figure 2 and Figure 3).
Mass spectrometry analysis deduced these molecular formulas.