Article

Journal of the American Society for Mass Spectrometry

, Volume 20, Issue 3, pp 529-538

First online:

The evaluation and comparison of trigonal and linear tricationic ion-pairing reagents for the detection of anions in positive mode ESI-MS

  • Molly M. WarnkeAffiliated withDepartment of Chemistry and Biochemistry, University of Texas Arlington
  • , Zachary S. BreitbachAffiliated withDepartment of Chemistry and Biochemistry, University of Texas Arlington
  • , Edra DodbibaAffiliated withDepartment of Chemistry and Biochemistry, University of Texas Arlington
  • , Eranda WanigasekaraAffiliated withDepartment of Chemistry and Biochemistry, University of Texas Arlington
  • , Xiaotong ZhangAffiliated withDepartment of Chemistry and Biochemistry, University of Texas Arlington
  • , Pritesh SharmaAffiliated withDepartment of Chemistry and Biochemistry, University of Texas Arlington
  • , Daniel W. ArmstrongAffiliated withDepartment of Chemistry and Biochemistry, University of Texas Arlington Email author 

Abstract

A general and sensitive method for detecting divalent anions by ESI-MS and LC/ESI-MS as positive ions has been developed. The anions are paired with tricationic reagents to form positively charged complexes. In this study, four tricationic reagents, 2 trigonal and 2 linear, were used to study a wide variety of anions, such as disulfonates, dicarboxylates, and inorganic anions. The limits of detection for many of the anions studied were often improved by tandem mass spectrometry. Tricationic pairing agents can also be used with chromatography to enhance the detection of anions. The tricationic reagents were also used to detect monovalent anions by monitoring the doubly charged positive complex. The limits of detection for some of the divalent anions by this method are substantially lower than by other current analytical techniques.