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Published on: February 23, 2017
Charge inversion via concurrent cation and anion transfer: application to corticosteroids.
Kerry M Hassell1, Yves LeBlanc, Scott A McLuckey
1Department of Chemistry, Purdue University, West Lafayette, IN 47907-1393, USA.
Rapid Communications in Mass Spectrometry : RCM
|January 25, 2011
Summary
A new charge inversion method uses polyamidoamine (PAMAM) dendrimer anions to selectively transfer anions to analyte ions. This process enables the selective screening of specific analytes like corticosteroids.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
- Ion Chemistry
Background:
- Ion/ion reactions are crucial in mass spectrometry.
- Developing selective ion/ion reactions is key for analyte detection.
- Charge inversion is a valuable tool for analyte characterization.
Purpose of the Study:
- To describe a novel charge inversion process for analyte analysis.
- To investigate the use of polyamidoamine (PAMAM) dendrimer anions as charge inversion reagents.
- To establish the requirements for selective charge inversion reactions.
Main Methods:
- Utilized polyamidoamine (PAMAM) half-generation dendrimer anions as reagents.
- Investigated ion/ion reactions involving analyte ions and dendrimer anions.
- Analyzed competing reaction pathways including neutralization and charge inversion.
- Examined the influence of reagent and analyte properties on reaction selectivity.
Main Results:
- A novel charge inversion process was achieved by removing a cation from an analyte and transferring an anion in a single encounter.
- Polyamidoamine (PAMAM) dendrimer anions were effective charge inversion reagents.
- Reaction selectivity was demonstrated, with corticosteroids being suitable analytes while estrone was not.
- Conditions for dominant charge inversion were identified, including reagent anion properties and analyte affinity for anions.
Conclusions:
- The described charge inversion reaction is highly selective.
- PAMAM dendrimer anions can be used for selective anion transfer to specific analyte cations.
- This method shows potential for the selective screening of appropriate analytes in complex mixtures.
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