中文摘要：

将新型电喷雾萃取电离源（EESI）和LTQ XL质谱仪耦合,在无需样品预处理情况下,建立了多种不同极性氨基酸的快速检测方法。新型EESI源优化后,检测模式为正离子模式,电离电压为4.0 kV,离子传输管温度150℃,喷雾气压为1.0 MPa。碰撞诱导裂解（CID）实验时,母离子隔离宽度1.5,碰撞能量17%～25%。本方法单个样品测定时间小于0.5 min,对多种氨基酸的检出限为0.14～26.2μg/L,且具有较宽的线性范围。直接检测复杂基体尿液中的丝氨酸和精氨酸时,平均回收率为82.6%～105.6%,测定结果的相对标准偏差（RSD）为2.2%～11.4%。本方法分析速度快,灵敏度高,基体影响小,适用于大量样品快速检测。

英文摘要：

A novel method,based on extractive electrospray ionization（EESI） tandem mass spectrometry（MS）,was developed for the direct detection of amino acids in biological fluids with minimal sample pretreatment.Based on our previous research,we constructed a new EESI ion source to improve the analytical performance and operation safety.We optimized EESI-MS conditions using representative amino acid standards.The reagent solvent（methanol ∶ water=1 ∶ 1） was electrosprayed at 5 μL/min at high voltage（＋4 kV,positive ion detection mode）.The temperature of the heated capillary was optimized to be 150 ℃.Collision induced dissociation（CID） experiments were done by applying 17%-25% of the collision energy to the precursor ions isolated with a window width of 1.5 mass/charge（m/z） units.The limit of detection（LOD） of these amino acids was in the range of 0.14–26.2 μg/L,and the linear dynamic range was larger than two orders of magnitude.The amino acid concentration in human urine samples was measured by the method,and the average time for a single sample analysis was less than 0.5 min.The recovery rates for different concentrations ranged from 82.6% to 105.6%,and the relative standard deviations（RSDs） ranged from 2.2% to 11.4%.This study showed that EESI-MS was a powerful tool for the rapid,sensitive,and quantitative detection of amino acids in complex biological samples.