Agilent 5977C GC/MSD 单四极杆气质联用仪

前言 癌症是造成消防行业中发病和死亡的一个主要病因 [1,2]。在火场中，消防员暴露于烟雾和高浓度有机化学物中，例如来自家具、地毯等的阻燃剂及其燃烧副产物。使用全谱采集模式下的高分辨率质谱对复杂基质中的环境污染物进行非目标分析具有很大优势，鉴定痕量化合物时尤其如此。为鉴定多环芳烃 (PAH)、多溴联苯醚 (PBDE) 等燃烧产物，我们采用了新型的高分辨率Agilent 7250 GC/Q-TOF。

本应用简报评估了 Agilent 8890/5977C 气相色谱/质量选择检测器 (GC/MSD) 在传统和高灵敏度水平下分析半挥发性有机化合物 (SVOCs) 的性能。GC/MSD 系统的初始校准范围为 0.2–150 μg/mL，在评估的 76 种分析物中，有97% 满足平均响应因子 (RF) 曲线拟合的要求。对方法进行修改以提高灵敏度，挑战更低浓度的校准范围0.01–10 μg/mL。在这些修改后的条件下，97% 的测试化合物仍符合或超过美国国家环境保护局 (US EPA) 方法 8270E 的平均 RF 拟合标准。这些结果表明分析物可能实现更低的检出限。

Abstract Gas chromatography/mass spectrometry (GC/MS) is integral to the analysis of semivolatile organic compounds (SVOCs) in environmental matrices. Recent pressure on the helium (He) supply has required organizations to actively investigate hydrogen (H2) carrier gas, but most GC/MS analyses have reduced sensitivity and hydrogenation or dechlorination in the sources. The Agilent HydroInert source retains the ability to analyze a wide calibration range (0.1 to 100 μg/mL) and meet the U.S. Environmental Protection Agency (EPA) method 8270 calibration criteria when using H2 carrier gas.

Abstract An Agilent 8890/5977C GC/MSD system coupled with an Agilent 8697 headspace sampler was successfully used with hydrogen carrier gas for the analysis of volatile organic compounds (VOCs) in drinking water. Recent concerns with the price and availability of helium have led laboratories to look for alternative carrier gases for their GC/MS methods. For GC/MS, hydrogen is the best alternative to helium, and offers potential advantages in terms of chromatographic speed and resolution. However, hydrogen is not an inert gas, and may cause chemical reactions in the mass spectrometer electron ionization (EI) source. This can lead to disturbed ion ratios in the mass spectrum, spectral infidelity, peak tailing, and nonlinear calibration for some analytes. Therefore, a new EI source for GC/MS and GC/MS/MS was developed, and optimized for use with hydrogen carrier gas. The new source, named HydroInert, was used in the system evaluated here. In addition to the new source, the chromatographic conditions were optimized to provide separation of 80 volatile compounds in 7 minutes. Standards and samples were analyzed in both scan and SIM data acquisition modes. For the scan data, spectra were deconvoluted with MassHunter Unknowns Analysis software and searched against NIST 20 to assess the spectral fidelity. In both modes, quantitative calibration was performed for the 80 compounds over the range of 0.05 to 25 μg/L. As demonstrated in this note, the system gives excellent results for the analysis of VOCs in drinking water.

Abstract This application note evaluates the performance of an Agilent 8890/5977C gas chromatography/mass selective detector (GC/MSD) in the analysis of semivolatile organic compounds (SVOCs) at both traditional and enhanced sensitivity levels. The GC/MSD system was initially calibrated with a range of 0.2 to 150 μg/mL with 97% of the 76 evaluated analytes meeting the requirement for average response factor (RF) curve fits. Method modifications to enhance sensitivity were applied to challenge a lower calibration range of 0.01 to 10 μg/mL. Under these amended conditions, 97% of the tested compounds also met or exceeded the United States Environmental Protection Agency (US EPA) Method 8270E criteria for average RF fits. These results demonstrated a potential for lower detection of analytes.

本应用简报介绍了使用气质联用系统 (GC/MS)，以氢气作为载气对大麻中的萜烯进行分析。GC/MS 已成为表征各种市售大麻品种的味道和气味的重要工具。利用配备新型电子轰击电离 (EI) 离子源（即 Agilent Hydro 惰性离子源）的 Agilent 8890 气相色谱和 5977C 单四极杆气质联用系统对 40 种可通过色谱分离的萜烯进行分析。优化后的方法提供了与使用氦气时相似的洗脱曲线，并且在各种化合物的校准范围内具有出色的线性，R 2 ≥ 0.99。所有目标分析物的准确度均在 92.5%–115.9% 之间，所有精密度相对标准偏差 (%RSD) 均低于 2.7%。对于希望使用更具可持续性的氢气载气进行萜烯分析的实验室，配备 9 mm 提取透镜的 Hydro 惰性离子源和小内径(0.18 mm) 色谱柱能够实现该目标，并获得同样出色的性能。

利用 Agilent 8860 GC 与 Agilent 5977B GC/MSD 系统对草莓中的农药进行筛查。这套经济有效的系统与适当的样品前处理、操作条件和软件工具相结合，为鉴定复杂基质（如食品）中的农药及其他污染物提供了一种实用的方法。该仪器配置将脉冲不分流进样、不锈钢 EI 离子源和保留时间纳入农药和环境污染物数据库中。完整分析分两个步骤完成。首先使用 Agilent MassHunter 未知物分析软件对样品进行筛查。该软件提供了自动化解卷积和谱库搜索功能，可鉴定任何目标农药或其他相关化学物质。然后，基于筛查结果分析样品以定量发现的任何目标化合物。利用购自当地杂货店的草莓样品来证明该方法的能力。