Blogs

Dealing with Metal Adduct Ions in Electrospray: Part 1

This Edition of MS solutions is discussing ways to deal with metal adduct Ions in electrospray.
| 1 min read
byO. David Sparkman

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.

The most commonly observed metal adduct ions in positive-ion electrospray analyses are single-charge sodium and potassium adducts, symbolized [M+Na]+ and [M+K]+ respectively. However, ions in electrospray can form with many other adducting species, e.g., ammonium ions [M+NH4]+; metal ions abstracted from the electrospray needle at high voltages, for example, [M+Fe]+; adducted solvent molecules such as [M+H+H2O]+; and, in negative-ion analysis, negative-charged adducting species like [M+Cl]–. Adduct species other than protonated molecules may also occur in atmospheric pressure chemical ionization (APCI) interfaces. Adduct ions in APCI must be volatile which means the ammonium, chloride, and water adducts described above can occur in APCI but the metal adduct ions cannot.

By reading the full article you will learn how important it is to understand the source of metal adduct ions and to know how to control their formation, particularly for quantitative applications, using two strategies that work reliably for dealing with these ions.



Meet the Author(s):

  • O. David Sparkman

    O. David Sparkman is currently an Adjunct Professor of Chemistry at the University of the Pacific in Stockton, California; Contractor to the National Institute of Standards and Technology Mass Spectrometry Data Center; President of ChemUserWorld.com; and a former American Chemical Society Instructor (1978–2006) and American Society for Mass Spectrometry Member-at-large for Education (2004–2006). At the University of the Pacific, Prof. Sparkman teaches courses in mass spectrometry and analytical chemistry and manages the mass spectrometry facility. Over the past 28 years, he has developed and taught five different ACS courses in mass spectrometry; he holds positions on the Editorial Advisory Boards of the European Journal of Mass Spectrometry and the HD Science GC/MS Update – Part B; and is the Book Review Editor for the European Journal of Mass Spectrometry. He is the author of Mass Spectrometry Desk Reference (Global View Publishing: Pittsburgh, PA, 1st ed. 2000; 2nd ed. 2006). Prof. Sparkman is a member of the Editorial Boards of the John Wiley Encyclopedia of Environmental Analysis and Remediation and Encyclopedia of Analytical Chemistry, Editor of and a contributor to the Mass Spectrometry Section of the Encyclopedia of Analytical Chemistry, and a contributor to the Encyclopedia of Environmental Analysis and Remediation. Along with J. Throck Watson, he developed the Mass Spectral Interpretation Quick Reference Guide. He also provides general consulting service in mass spectrometry for a number of instrument manufacturers, manufacturing companies, and government agencies.

Here are some related topics that may interest you:

Loading Next Article...
Loading Next Article...