Selective and sensitive LC-MS determination of avenanthramides in oats

A new liquid chromatographic - mass spectrometric (LC-MS) method suitable for the determination of avenanthramides in oats has been developed. The avenanthramides were detected using positive ion electrospray with selective ion monitoring of protonated ions [M+H](+). The separation of avenonthramides was achieved on Genesis C-18 column by using acetonitrile aqueous formic acid as mobile phase and gradient elution. The effects of buffer nature and concentration on separation, peak shape and intensity of mass spectrometric signal were investigated. The detection limits ranged between 10 and 30 ng mL(-1) for standard solutions when using 1 mu L injection. The developed LC-MS method was found to be superior over commonly used liquid chromatographic methods with UV detection in terms of selectivity and sensitivity. The applicability of the method to real samples (oat groats) was demonstrated.