Greg Wells

Greg Wells is with Varian, Inc., Palo Alto, California.


Why Use Signal-To-Noise As a Measure of MS Performance When It Is Often Meaningless?

May 01, 2011

Signal-to-noise of a chromatographic peak from a single measurement has been used determine the performance of two different MS systems, but this parameter can no longer be universally applied and often fails to provide meaningful estimates of the instrument detection limits (IDL).

The Analysis of Semivolatile Compounds in Environmental and Crude Vegetable Extracts by Ion-Trap Mass Spectrometry

November 01, 2007

Today's ion traps use advanced scanning techniques such as automatic gain control, axial modulation, and triple resonance scanning, resulting in efficient control of both ionization and optimal storage of ions in the trap during analysis. These instruments provide excellent sensitivity and quantitative data, even in "dirty" samples.