School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Boulevard d'Yvoy 20, 1211 Geneva 4, Switzerland.
School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Boulevard d'Yvoy 20, 1211 Geneva 4, Switzerland.
J Chromatogr A. 2014 Apr 25;1339:174-84. doi: 10.1016/j.chroma.2014.03.006. Epub 2014 Mar 11.
The recent market release of a new generation of supercritical fluid chromatography (SFC) instruments compatible with state-of-the-art columns packed with sub-2μm particles (UHPSFC) has contributed to the reemergence of interest in this technology at the analytical scale. However, to ensure performance competitiveness of this technique with modern analytical standards, a robust hyphenation of UHPSFC to mass spectrometry (MS) is mandatory. UHPSFC-MS hyphenation interface should be able to manage the compressibility of the SFC mobile phase and to preserve as much as possible the chromatographic separation integrity. Although several interfaces can be envisioned, each will have noticeable effects on chromatographic fidelity, flexibility and user-friendliness. In the present study, various interface configurations were evaluated in terms of their impact on chromatographic efficiency and MS detection sensitivity. An interface including a splitter and a make-up solvent inlet was found to be the best compromise and exhibited good detection sensitivity while maintaining more than 75% of the chromatographic efficiency. This interface was also the most versatile in terms of applicable analytical conditions. In addition, an accurate model of the fluidics behavior of this interface was created for a better understanding of the influence of chromatographic settings on its mode of operation. In the second part, the most influential experimental factors affecting MS detection sensitivity were identified and optimized using a design-of-experiment approach. The application of low capillary voltage and high desolvation temperature and drying gas flow rate were required for optimal ESI ionization and nebulization processes. The detection sensitivity achieved using the maximized UHPSFC-ESI-MS/MS conditions for a mixture of basic pharmaceutical compounds showed 4- to 10-fold improvements in peak intensity compared to the best performance achieved by UHPLC-ESI-MS/MS with the same MS detector.
新一代与最先进的亚 2μm 颗粒装填柱（UHPSFC）兼容的超临界流体色谱（SFC）仪器最近在市场上推出，这促使人们重新对分析规模的这项技术产生兴趣。然而，为了确保这项技术与现代分析标准的性能竞争力，必须将超高效 SFC 与质谱（MS）进行稳健的联用。UHPSFC-MS 联用接口应能够管理 SFC 流动相的可压缩性，并尽可能保持色谱分离的完整性。虽然可以设想几种接口，但每种接口都会对色谱保真度、灵活性和用户友好性产生明显影响。在本研究中，根据对色谱效率和 MS 检测灵敏度的影响，评估了各种接口配置。发现包括分流器和补加溶剂入口的接口是最佳折衷方案，在保持超过 75%的色谱效率的同时，显示出良好的检测灵敏度。该接口在适用的分析条件方面也具有最大的通用性。此外，还创建了该接口流体动力学行为的准确模型，以更好地理解色谱设置对其工作模式的影响。在第二部分中，使用实验设计方法确定并优化了影响 MS 检测灵敏度的最具影响力的实验因素。需要采用低毛细管电压、高去溶剂化温度和干燥气流速，以实现最佳的 ESI 离子化和雾化过程。与使用相同 MS 检测器的 UHPLC-ESI-MS/MS 获得的最佳性能相比，使用优化后的 UHPSFC-ESI-MS/MS 条件对碱性药物混合物进行检测时，峰强度提高了 4 至 10 倍。
