Fujito Yuka, Hayakawa Yoshihiro, Izumi Yoshihiro, Bamba Takeshi
Division of Analytical and Measuring Instruments, Shimadzu Corporation, 1 Kuwabaracho Nishinokyo Nakagyo-ku, Kyoto 604-8511, Japan.
Division of Metabolomics, Research Center for Transomics Medicine, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
J Chromatogr A. 2017 Jul 28;1508:138-147. doi: 10.1016/j.chroma.2017.05.071. Epub 2017 Jun 2.
Supercritical fluid chromatography/mass spectrometry (SFC/MS) has great potential in high-throughput and the simultaneous analysis of a wide variety of compounds, and it has been widely used in recent years. The use of MS for detection provides the advantages of high sensitivity and high selectivity. However, the sensitivity of MS detection depends on the chromatographic conditions and MS parameters. Thus, optimization of MS parameters corresponding to the SFC condition is mandatory for maximizing performance when connecting SFC to MS. The aim of this study was to reveal a way to decide the optimum composition of the mobile phase and the flow rate of the make-up solvent for MS detection in a wide range of compounds. Additionally, we also showed the basic concept for determination of the optimum values of the MS parameters focusing on the MS detection sensitivity in SFC/MS analysis. To verify the versatility of these findings, a total of 441 pesticides with a wide polarity range (logP from -4.21 to 7.70) and pKa (acidic, neutral and basic). In this study, a new SFC-MS interface was used, which can transfer the entire volume of eluate into the MS by directly coupling the SFC with the MS. This enabled us to compare the sensitivity or optimum MS parameters for MS detection between LC/MS and SFC/MS for the same sample volume introduced into the MS. As a result, it was found that the optimum values of some MS parameters were completely different from those of LC/MS, and that SFC/MS-specific optimization of the analytical conditions is required. Lastly, we evaluated the sensitivity of SFC/MS using fully optimized analytical conditions. As a result, we confirmed that SFC/MS showed much higher sensitivity than LC/MS when the analytical conditions were fully optimized for SFC/MS; and the high sensitivity also increase the number of the compounds that can be detected with good repeatability in real sample analysis. This result indicates that SFC/MS has potential for practical use in the multiresidue analysis of a wide range of compounds that requires high sensitivity.
超临界流体色谱/质谱联用技术（SFC/MS）在高通量以及同时分析多种化合物方面具有巨大潜力，近年来已得到广泛应用。使用质谱进行检测具有高灵敏度和高选择性的优点。然而，质谱检测的灵敏度取决于色谱条件和质谱参数。因此，在将SFC与MS连接时，针对SFC条件优化质谱参数对于最大化性能而言是必不可少的。本研究的目的是揭示一种方法，用于确定在广泛的化合物中进行质谱检测时流动相的最佳组成和补充溶剂的流速。此外，我们还展示了在SFC/MS分析中专注于质谱检测灵敏度来确定质谱参数最佳值的基本概念。为了验证这些发现的通用性，总共研究了441种极性范围广泛（logP从-4.21至7.70）且具有不同pKa值（酸性、中性和碱性）的农药。在本研究中，使用了一种新的SFC-MS接口，该接口通过将SFC与MS直接耦合，能够将全部洗脱液体积转移到MS中。这使我们能够比较对于引入MS的相同样品体积，LC/MS和SFC/MS之间质谱检测的灵敏度或最佳质谱参数。结果发现，某些质谱参数的最佳值与LC/MS完全不同，并且需要针对SFC/MS进行特定的分析条件优化。最后，我们使用完全优化的分析条件评估了SFC/MS的灵敏度。结果，我们证实当分析条件针对SFC/MS完全优化时，SFC/MS显示出比LC/MS更高的灵敏度；并且高灵敏度还增加了在实际样品分析中能够以良好重复性检测到的化合物数量。这一结果表明，SFC/MS在需要高灵敏度的多种化合物的多残留分析中具有实际应用潜力。
