Ultrasensitive ambient mass spectrometric analysis with a pin-to-capillary flowing atmospheric-pressure afterglow source.
Ultrasensitive ambient mass spectrometric analysis with a pin-to-capillary flowing atmospheric-pressure afterglow source.
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DOI：
10.1021/ac201053q
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发表时间：
2011-07-15
影响因子：
7.4
通讯作者：
Hieftje, Gary M.
中科院分区：
文献类型：
--
作者：
Shelley, Jacob T.;Wiley, Joshua S.;Hieftje, Gary M.
环境解吸/电离质谱的出现使得人们对能够直接对分析物进行采样和电离的电离源产生了浓厚兴趣。其中一种越来越受关注的电离源是流动大气压余辉（FAPA）。FAPA已被证明能够直接解吸/电离任何相态（固态、液态或气态）的样品，且具有令人瞩目的检测限（<100飞摩尔）。还表明FAPA比其他基于等离子体的电离源受竞争电离基质效应的影响更小。然而，最初的FAPA设计存在背景水平较高、负离子模式下背景光谱杂乱以及芳香族分析物显著氧化等问题，这些最终影响了分析物的鉴定和定量。在本研究中，发现将FAPA的结构从针 - 板几何形状改为针 - 毛细管几何形状可大幅提高性能。正离子和负离子电离模式下的背景信号分别降低了89%和99%。此外，毛细管阳极大大减少了可能导致分析物氧化的原子氧的量。通过红外热成像技术比较了两种电离源中与样品相互作用的气流温度，该温度对解吸能力有重大影响。通过测定正离子和负离子模式下的多种化合物（包括农用化学品和爆炸物）来评估新FAPA结构的性能。发现对农用化学品阿特拉津直接测定的检测限为4阿摩尔，并且似乎受限于光谱仪。还展示了使用针 - 毛细管FAPA快速筛选大量液态样品中分析物的能力。
The advent of ambient desorption/ionization mass spectrometry has resulted in a strong interest in ionization sources that are capable of direct analyte sampling and ionization. One source that has enjoyed increasing interest is the Flowing Atmospheric-Pressure Afterglow (FAPA). FAPA has been proven capable of directly desorbing/ionizing samples in any phase (solid, liquid, or gas) and with impressive limits of detection (<100 fmol). The FAPA was also shown to be less affected by competitive-ionization matrix effects than other plasma-based sources. However, the original FAPA design exhibited substantial background levels, cluttered background spectra in the negative-ion mode, and significant oxidation of aromatic analytes, which ultimately compromised analyte identification and quantification. In the present study, a change in the FAPA configuration from a pin-to-plate to a pin-to-capillary geometry was found to vastly improve performance. Background signals in positive- and negative-ionization modes were reduced by 89% and 99%, respectively. Additionally, the capillary anode strongly reduced the amount of atomic oxygen that could cause oxidation of analytes. Temperatures of the gas stream that interacts with the sample, which heavily influences desorption capabilities, were compared between the two sources by means of IR thermography. The performance of the new FAPA configuration is evaluated through the determination of a variety of compounds in positive- and negative-ion mode, including agrochemicals and explosives. A detection limit of 4 amol was found for the direct determination of the agrochemical ametryn, and appears to be spectrometer-limited. The ability to quickly screen for analytes in bulk liquid samples with the pin-to-capillary FAPA is also shown.
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影响因子：
7.4
作者：
Cody, RB;Laramée, JA;Durst, HD
通讯作者：
Durst, HD
DOI：
10.1016/j.jasms.2008.12.020
发表时间：
2009-05-01
影响因子：
3.2
作者：
Shelley, Jacob T.;Wiley, Joshua S.;Hieftje, Gary M.
通讯作者：
Hieftje, Gary M.
影响因子：
4.2
作者：
Jecklin, Matthias C.;Gamez, Gerardo;Zenobi, Renato
通讯作者：
Zenobi, Renato
影响因子：
1.8
作者：
Nilles, J. Michael;Connell, Theresa R.;Durst, H. Dupont
通讯作者：
Durst, H. Dupont
影响因子：
7.4
作者：
Shelley, Jacob T.;Ray, Steven J.;Hieftje, Gary M.
通讯作者：
Hieftje, Gary M.