电喷雾萃取电离质谱法检测1-羟基芘

Detection of 1-Hydroxypyrene by Extractive Electrospray Ionization Mass Spectrometry

采用电喷雾萃取电离质谱(EESI-MS)分析致癌性环境有机污染物多环芳烃(PAHs)生物标志物1-羟基芘(1-OHP),探究1-OHP在EESI源中电离的可行性,考察ESI溶剂和样品溶液组成对方法灵敏度的影响,初步建立1-OHP的EESI-MS半定量分析方法。结果表明,溶液中1-OHP能够在EESI源中有效电离,生成准分子离子[M-H]-(m/z217),并得到其二级质谱特征碎片离子[M-H-CO]-(m/z189);水、甲醇、乙醇、正丙醇和正丁醇5种ESI溶剂中,使用甲醇时,离子峰m/z217信噪比最大。样品溶液中甲醇含量越高,离子峰m/z217强度越强。离子峰m/z217强度与1-OHP浓度在10～200μg/L内的线性相关性相对最好;相关系数(R)0.982;相对标准偏差(RSD)为3.4%～14.0%(n=5);定量下限约为10μg/L(S/N=10);单次检测时间小于0.5min。

A method for the detection of 1-hydroxypyrene（1-OHP） using extractive electrospray ionization mass spectrometry（EESI-MS） has been investigated,including the ionization of 1-OHP in a home-made EESI source,effects of the composition of ESI solvent and sample solvent on signal intensity,and semi-quantification analysis.The results indicated that,1-OHP can be effectively extracted and ionized in the EESI source,producing the quasi-molecular ion -（m/z 217） and MS/MS fragment ion [M-H-CO]-（m/z 189）;when water,methanol,ethanol,n-propanol and n-butanol were used as ESI solvents,respectively,the highest signal to noise ratio（S/N） was achieved while using methanol as ESI solvent;with the increase of methanol content in sample solution,the signal intensity increased significantly,and the signal intensity of m/z 217 in methanol was more than 200 times higher than that in water.The signal intensity of m/z 217was linearly related with the concentration of 1-OHP in methanol within the concentration range of 10-200 μg/L;the correlation coefficient（R） was 0.982,the relative standard deviations（RSD） were 3.4%-14.0%（n=5）,the quantitative detection limit（LOD） for 1-OHP in methanol was about 10 μg/L（S/N=10）,and the analytical time of each detection was less than 0.5 min.