Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4-3-11, Takeda, Kofu, Yamanashi 400-8511, Japan.
Analyst. 2018 Nov 5;143(22):5552-5558. doi: 10.1039/c8an01113c.
High-pressure electrospray ionization (HP-ESI) performed under super-atmospheric pressure allows a stable and efficient electrospray of pure aqueous and/or superheated solutions even under a μL min-1 flow rate regime. In this paper, we report the direct coupling of the HP-ESI source to high-temperature liquid chromatography (HT-LC) operated at ≤30 μL min-1 flow rates. In addition to ESI, the ion source functions as a back-pressure regulator to keep the mobile phase in the liquid phase when the column is heated to >100 °C. Under an ion source pressure of 7 bar, the LC column can be operated up to 160 °C. LC is performed under isocratic elution, and besides the isothermal mode, the temperature of the column can also be programmed to increase the selectivity while keeping the ion source at a constant temperature. For a given solution flow rate, the analytical time can be shortened by increasing the column temperature. HT-LC-ESI-MS using pure water as the mobile phase with a capillary column is also demonstrated.
在超大气压下进行的高压电喷雾电离 (HP-ESI) 可实现稳定、高效的纯水溶液和/或过热溶液的电喷雾，即使在 μL min-1 的流速下也能如此。本文报道了在 ≤30 μL min-1 的流速下，将 HP-ESI 源与高温液相色谱 (HT-LC) 直接耦合。除了 ESI 之外，该离子源还可用作背压调节器，当色谱柱加热到 >100 °C 时，可使流动相保持液相。在离子源压力为 7 bar 的情况下，LC 柱可在 160 °C 下运行。LC 采用等度洗脱，除了等温模式外，还可以对柱温进行编程，在保持离子源温度恒定的情况下增加选择性。对于给定的溶液流速，可以通过提高柱温来缩短分析时间。还展示了使用纯水作为流动相的毛细管柱的 HT-LC-ESI-MS。
