Combined Analyzer Technologies

Abstract

There is no one single answer to the question of why different analyzer combinations are being used because the driving force to construct and use such instruments changes with time. Certainly one of the driving forces is the need for further technological development; for example, the need of better sensitivity and higher mass resolution for atomic [1] and molecular [2] mass determination and structure elucidation of natural compounds [3]. This was subsequently achieved by the introduction of double focusing sector instruments (combination of magnetic and electrostatic analyzers) [4,5]. The study of natural compounds, for instance, alkaloids and steroids [6], pushed mass spectrometry to a higher mass range (up to 1 kDa and more). The possibility to analyze larger molecules induced again the development of new ionization methods, thus adding “soft” ionization techniques to the commonly used electron impact ionization (EI). Methods like chemical ionization (CI), field desorption (FD), and fast atom bombardment (FAB) opened a wide research field for mass spectrometry [7–10].