High Resolution Mass Spectrometry (HRMS)

Microscale characterization of marine organic matter, E. C. Minor 1996

An understanding of the nature of marine dissolved and particulate organic material (DOM & POM), dissolved organic carbon (DOC) is needed if we are to be able to fully describe and quantitate the cycling of carbon between the atmosphere, water column and sediments. Even a semi-quantitative analysis capable of highlighting differences and similarities between the matter in these various pools may prove useful in determining where to focus more detailed investigations. Much of Dr. Elizabeth Minor’s thesis work involved utilizing the low energy ionization capabilities of the Facility’s Autospec-Q MS to develop and apply a rapid analysis for just this purpose [refs]. Her continuing studies of these materials have made ongoing use the Facility’s Autospec-Q [Minor et al., 1996].

LC/MS of free radical adducts, C. G. Johnson 1996

Free radicals have an important role in many biological and environmental processes, but their identification and detection is difficult specifically due to their highly reactive nature. We had previously used a probe based analysis on our Finnigan 4500 to demonstrate the successful stabilization of these species as their adducts of a fluorescamine derivatized nitroxide (Kieber et al., 1992). Dynamic liquid secondary ion mass spectrometry on the Autospec-Q provided the platform to develop an LC-HRMS method for simultaneously separation and identification (and potential quantification) of the trapped radical adducts (Johnson et al., 1996).

Determination of alkenone unsaturation indices, C. G. Johnson 2003

The extent of unsaturation of certain long chain (C37) alken-2-ones (“alkenones”) biosynthesized by a class of marine algae (Haptophyceae) has become one of the principal paleoceanographic quantities measured since the discovery of its correlation with sea surface temperature. This measurement is classically made by purifying a sediment lipid extract, and separating and quantifying the resulting alkenone mixture by GC. CGJ demonstrated that by using the high mass resolving power of the Autospec-Q, it was possible to determine the alkenone ratio directly from the crude lipid extract without a wet chemical or chromatographic separation (Johnson et al., 2003).