Interpretation of electrospray and atmospheric pressure chemical ionization mass spectra of 10-formyl-7,8-dihydrofolic acid and 5-formyl-5,6,7,8-tetrahydropteroic acid.
Interpretation of positive- and negative-ion electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) mass spectra of 10-formyl-7,8-dihydrofolic acid (10-FDHFA) and 5-formyl-5, 6,7,8-tetrahydropteroic acid (5-FTHPA) is discussed. ESI mass spectra enable unambiguous molecular weight (MW) determination. In addition to the determination of MW, APCI mass spectra also make possible structure elucidation of 10-FDHFA and 5-FTHPA. ESI and APCI are complementary ionization techniques and appear to be useful alternatives to conventional electron ionization (EI) for the structure elucidation of non-volatile carboxylic acids. Prior to mass spectral analysis, the acids investigated were separated by reverse-phase high-performance liquid chromatography (HPLC).
Holcapek
M
M
Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Nám. Cs. Legií 565, 53210 Pardubice, Czech Republic.
Jandera
P
P
D001274:Atmospheric Pressure; D005492:Folic Acid / Q000737:chemistry*; D013058:Mass Spectrometry / Q000379:methods*; D011622:Pterins / Q000737:chemistry*; D055672:Static Electricity
C121082:5-formyl-5,6,7,8-tetrahydropteroic acid; D011622:Pterins; D005492:Folic Acid; C120486:10-formyl-7,8-dihydrofolic acid