Mass Spectrometry

This technical article explains the confusion resulting from molecular weight and the nominal mass, monoisotopic mass and average molar mass.

An illustrative example of the use of isotope peak ratios to determine an elemental composition.

This technical article comprises a discussion of the role of isotope peak intensities obtained using mass spectrometry in determining an elemental composition.

Mass spectrometry has long been a valuable quantitative tool used across many industries for numerous applications including food [1], beverage [2], pharma [3] and environmental analysis [4]. Its utility ranges from use as an alternative detector to...

by Gary Mallard and O. David Sparkman

For AMDIS to be as effective as possible, it is essential to have high quality target libraries. These can either come from standards taken with the same instrument that the data is analysed on or from the NIST...

by Gary Mallard and O. David Sparkman

In the first two parts of the discussion of setting up AMDIS the basics of running an analysis with retention index filtering as well as a simple analysis were discussed. In this final part of the set up...

by Gary Mallard and O. David Sparkman

In the last part of this AMDIS discussion, the setting up and running of a simple analysis was discussed. However, to take full advantage of AMDIS it is far better to make use not only of the mass spectral...

by Gary Mallard and O. David Sparkman

AMDIS is designed to do analysis for target compounds in a GC/MS data file. To do the analysis you need a completed data file (AMDIS reads most current and many older instrument formats as well as standard...

by Gary Mallard and O. David Sparkman

The identification of components by GC/MS in complex mixtures has essentially two parts – extracting a spectrum that is due to a single component and then identifying the component, usually through a library...

An electrospray LC/MS interface consists of an enclosed, atmospheric pressure chamber whereby the HPLC effluent enters this chamber through a capillary tube. This is surrounded by a second, concentric tube through which a nebulizing gas is applied....

Previously we discussed the fundamental issue of metal adduct ion formation in electrospray LC/MS including method development strategies for dealing with adduct ions. This article will examine a real-world application which employs these...

In this technical article you will learn about the adduction of alkali metal ions (Na, K), to analyte molecules with the term “metal adduct ion” being used to refer to these species.

Reducing the internal diameter of your HPLC columns is an advantage for electrospray (ESI) LC/MS users. To understand this, two characteristics of ESI must be understood: (1) how response (i.e., peak area or height), is related to analyte...