Reduced EI Source Contamination and Improved System Longevity with the Intuvo 9000 GC for Environmental Analysis

New Environmental Monitoring Techniques for Organics
Oral Presentation

Prepared by R. Veeneman, M. Giardina, T. Anumol, J. Hedrick
Agilent Technologies, 2850 Centerville Rd, Wilmington, DE, 19808, United States


Contact Information: [email protected]; 302-419-8909


ABSTRACT

As certain semivolatile organic compounds are considered environmental contaminants there are established methods by world regulatory agencies, like the United States Environmental Protection Agency. These methods have set performance criteria that must be met before reporting on this type of contamination. One of these criteria is the stability of internal standard response. A comparison of ISTD response between an Agilent 9000 GC coupled to a mass spectrometer equipped with an EI source and an Agilent 7890 GC with the same detector configuration showed a significant difference in the number of soil extract injections required to cause a 50% reduction in ISTD response. The 7890 GC/MS was challenged twice with matrix, starting with a clean ion source and new column each time. In the first study, a total of 240 matrix injections was performed before the internal standard responses dropped below 50% compared to the initial calibration. For the second study, a total of 120 matrix injections was performed before the internal standard response dropped below 50%. For the Intuvo 9000 GC/MS a total of 680 injections were performed without the internal standard response dropping below 50%. Internal standard response was restored on the 7890 GC/MS when the contaminated ion source was replaced by a clean source indicating source contamination was directly responsible for loss of response. With the unique microfluidic flow path of the Intuvo GC/MS, ISTD response stability can be improved over traditional GC systems.