Salbutamol (MW 239.31) is a selective β2-receptor agonist, main effect for the treatment of asthmatic bronchitis, bronchial asthma, and emphysema-induced bronchospasm. The protonated molecular ion at m/z 240 and fragment ions at m/z 222, 166, and 148 can be found in the full-scan mass spectrum (Supplementary Figure S-3i). The ionic fragments of m/z 222, 166, and 148 are generated by the loss of H2O, [H2O+C(CH3)2CH2], [2H2O+C(CH3)2CH2]. According to the data of collision-induced dissociation of protonated salbutamol (Supplementary Figure S-1i), MPT ionization technology can help to obtain abundant, accurate information of protonated molecular ion and fragment ions of analytes without a tandem mass spectrometer.