Tandem MS Library Development and Possible Screening Exercise Using the NIST/EPA Library
Monday, March 12th, 2012
04:30 - 06:30 PM Room: 312A
Lawrence B Zintek and Stephen Stein
Over the last decade there has been interest in the development of transferable LC/MS libraries. It has been demonstrated that after accounting for differences in collision energy, spectra for a compound are instrument independent. Moreover, while ion intensities may vary, major fragment ions are the same with few exceptions. Over the last few years NIST has extended its development of GC/MS Libraries and Search Programs to include Tandem MS Spectra. This library is now comprised of over 95,000 spectra for some 5,800 compounds. A range of other libraries are currently being constructed by other agencies and vendors. The EPA Chicago Regional Laboratory library database and protocol was multi-lab validated and used during the 2008 Democratic and Republican National Conventions. Such libraries may be effectively used for screening to assist in the identification of known/unknowns using high resolution mass spectrometry.
The U.S. Environmental Protection Agency may conduct an exercise utilizing the NIST/EPA Tandem MS Library Database to tentatively identify analytes of interest to EPA. This would employ a direct injection liquid chromatography mass spectrometry methodology. Direct injection does not require a time-consuming extraction step. The method will be used for initial rapid detection and screening for unknown contaminants. This method can be used by other laboratories involved in a response event (e.g., utility, state, EPA regional, and commercial laboratories). This methodology is for the detection of contaminants using the NIST/EPA library and may involve crude semi-quantitation based upon comparison of a surrogate response to the target analyte response. Anyone interested in LC/MS libraries, who would like to contribute to the database, or has interest in a volunteer multi-laboratory exercise to verify or validate methodologies should attend.