Retain Your Spectral Fidelity: Using H2 Carrier Gas and a Novel EI Source for EPA 8270 With GC/MS and GC-MS/MS Systems

New Organic Monitoring Techniques (Session 2)
Oral Presentation

Prepared by A. Smith Henry1, B. Mock2, A. Andrianova1, A. McQuay1, B. Quimby1
1 - Agilent Technologies Inc., 2850 Centerville Road, Wilmington, DE, 19808, United States
2 - Pace Analytical National Center for Testing & Innovation Laboratory, 12065 Lebanon Rd, Mt Juliet, TN, 37122, United States

Contact Information: [email protected]; 302-636-8252


Switching to hydrogen for gas chromatography (GC) and GC/MS analyses is a more frequently discussed topic as helium price and availability concerns have increased in recent years. Since hydrogen is a reactive gas, hydrogenation and dechlorination reactions can and do occur in the mass spectrometer electron ionization (EI) source. These reactions can make applying hydrogen carrier gas to EPA methods, like 8270, difficult due to altered mass spectral ion ratios, spectral infidelity, and peak tailing. The development of a new and novel EI source to address these hydrogen-related issues improves performance with hydrogen carrier gas in GC/MS and GC/MS/MS analysis, specifically EPA method 8270(E). The novel EI source also introduces the ability to shift to more efficient columns and a faster analysis time, allowing for EPA 8270 analysis in under 6 minutes with dynamic MRM (multiple reaction monitoring) on a GC-MS/MS system. Also, calibration performance is dramatically improved with a significant (>50%) decrease in the number of compounds requiring a quadratic fit, when compared to the conventional EI source equipped with a 9 mm lens over a calibration range of 0.1-100 ppm.