Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP), Department of Environmental Science and Engineering, Fudan University, Shanghai, China.
State Key Laboratory of Marine Environmental Sciences, Xiamen University, Xiamen, China.
PLoS One. 2018 Nov 12;13(11):e0206488. doi: 10.1371/journal.pone.0206488. eCollection 2018.
A method was developed for simultaneous determination of 15 amino acids and 7 alkyl amines. The method was based on the employment of high performance liquid chromatography/fluorescence detection and online derivatization with o-phthaldiadehyde. The 22 derivatives were separated within 30 min including the equilibration time and detected by a fluorescence detector at an excitation wavelength of 230 nm and emission wavelength of 450 nm. The analysis procedure was satisfactorily validated by the reproducibility, recovery, linearity and detection limit of the analytes. The relative standard deviations (RSDs) of retention time and peak area for individual amino acids and alkyl amines were consistently less than 0.30% and 2.35%, respectively. Good recovery values ranging from 70% to 109% were obtained. The proposed method showed good linearity (R2≥0.99) in the range of 0.125-125 μM/L for amino acids and 2.5-5000 ng/L for alkyl amines. The detection limit ranged from 0.13 pM to 0.37 pM for individual amino acids and from 0.9 ng to 7.2 ng for individual alkyl amines. The developed and validated method was successfully applied to the quantitative analysis of amino acids and alkyl amines in continental and marine aerosols in China. Among the identified organic nitrogen compounds, 7 amino acids and 6 alkyl amines were detected in every aerosol sample. Glycine was the dominant amino acid, with the average of 130.93 pmol/m3 (accounting for 83% of the total amino acids) and 137.22 pmol/m3 (accounting for 66% of the total amino acids) in continental and marine aerosols in China, respectively. Methylamine and ethanolamine were the most abundant alkyl amines, contributing 87% and 64% to the total alkyl amines in continental and marine aerosols in China, respectively. This work provided an accurate, sensitive and simple method to determine simultaneously amino acids and alkyl amines, and applied the proposed method to the first investigation of amino acids in Shanghai and amino acids and alkyl amines in Huaniao Island in China. The finding of considerable amino acids and alkyl amines in continental and marine aerosols may exert significant implications on nitrogen cycling and atmospheric chemistry.
建立了一种同时测定 15 种氨基酸和 7 种烷基胺的方法。该方法基于高效液相色谱/荧光检测，并采用邻苯二醛在线衍生化。在包括平衡时间在内的 30 分钟内，分离了 22 种衍生物，并通过荧光检测器在 230nm 的激发波长和 450nm 的发射波长下进行检测。通过对分析物的重现性、回收率、线性和检测限的验证，证明了分析程序是令人满意的。单个氨基酸和烷基胺的保留时间和峰面积的相对标准偏差（RSD）始终小于 0.30%和 2.35%。回收率在 70%到 109%之间。所提出的方法在 0.125-125μM/L 范围内对氨基酸和 2.5-5000ng/L 范围内对烷基胺具有良好的线性（R2≥0.99）。单个氨基酸的检测限范围为 0.13pM 至 0.37pM，单个烷基胺的检测限范围为 0.9ng 至 7.2ng。该方法已成功应用于中国大陆和海洋气溶胶中氨基酸和烷基胺的定量分析。在所鉴定的有机氮化合物中，每个气溶胶样品中均检测到 7 种氨基酸和 6 种烷基胺。甘氨酸是主要的氨基酸，在中国大陆和海洋气溶胶中的平均浓度分别为 130.93pmol/m3（占总氨基酸的 83%）和 137.22pmol/m3（占总氨基酸的 66%）。甲胺和乙醇胺是最丰富的烷基胺，分别占中国大陆和海洋气溶胶中总烷基胺的 87%和 64%。该工作提供了一种准确、灵敏和简单的同时测定氨基酸和烷基胺的方法，并将所提出的方法应用于上海的氨基酸首次调查以及中国环鸟岛的氨基酸和烷基胺调查。在大陆和海洋气溶胶中发现相当数量的氨基酸和烷基胺可能对氮循环和大气化学产生重要影响。
