Fig. 1.

Generation of multiple molecular ions from a single PC molecular species was reduced by adding an alkali-metal salt to the matrix solution. A: Spectra obtained from sections of mouse brain-homogenate using matrix solution with/without potassium acetate. The use of the salt-added matrix solution allowed multiple molecular ion-forms of PCs to be reduced to a single potassiated molecular ion form. B: Ion intensities of two PC species, PC (diacyl-16:0/16:0) and PC (diacyl-16:0/18:1), in three molecular ion forms, protonated, sodiated, and potassiated molecules. Error bars indicate SD.