Atmospheric pressure chemical ionization (APcI) liquid chromatography mass spectrometry: Characterization of natural antioxidants

The combination of liquid chromatography with mass spectrometry (LC-MS) allows non-volatile and thermally sensitive compounds to be handled. The key feature, regarding LC flowrate and MS vacuum requirements, is the LC-MS interface system. Atmospheric pressure chemical ionization (APcI) is a sensitive and widely applicable method which gives primarily molecular weight information with the ability to provide structural information if required. Applications concerning the characterization of natural antioxidants from rosemary, sage and barley are reported: the main functional groups of diterpenes (rosmanol and derivatives), the aglycone part of glycosylated flavones and the different units of polymers of flavan-3-ols (procyanidins, prodelphinidins) are shown.