Rapid determination of underivatized amino acids in fertilizers by ultra high performance liquid chromatography coupled to tandem mass spectrometry

[摘要] The analysis of 19 underivatized protein amino acids by ultra high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) is studied. Amino acids were separated by reversed phase, adding to the mobile phase pentadecafluorooctanoic acid as ion pairing reagent. The selected amino acids were eluted in less than 8 min. MS/MS parameters were optimized, using electrospray ionization (ESI) in positive mode for the detection of the amino acids. A simple solid-liquid extraction with water and heptafluorobutyric acid was used for the extraction of the compounds from the fertilizer. All amino acids were extracted with recoveries higher than 70% and relative standard deviation (RSD) lower than 22.5% (inter-day precision). Limits of quantification were always lower than 100 mg kg−1 of sample, for all the compounds. The validated method is simple, fast and sensitive and it has been applied for the determination of amino acids in fertilizers...

[学科分类] 分析化学