The measurement of charge for induction-based fluidic MALDI dispense event and nanoliter volume verification in real time

  • Brent Hilker
  • Kevin J. Clifford
  • Andrew D. Sauter
  • Andrew D. Sauter
  • Julie P. HarmonEmail author
Application Note


This study preliminarily investigates whether nanoliter volumes of concentrated polar liquids and organic monomers launched to targets using induction based fluidics (IBF) can be verified through the real time charge measurements. We show that using a nanoliter IBF dispensing device and nanocoulomb meter, charge measurements made on nanoliter drops in real time are correlated with surface area following Gauss’s Law. We infer the “induction only” formation of the double layer showing the ability to determine nanoliter volumes, nearly instantaneously, in real time. We discuss the implications that these observations may have for on improving/monitoring MALDI quantitation and its quality control.


Double Layer MALDI MALDI Mass Spectrometry Faraday Cage Charge Measurement 
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Supplementary material

13361_2011_200601064_MOESM1_ESM.doc (158 kb)
Supplementary material, approximately 161 KB.


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Copyright information

© American Society for Mass Spectrometry 2009

Authors and Affiliations

  • Brent Hilker
    • 2
  • Kevin J. Clifford
    • 2
  • Andrew D. Sauter
    • 1
  • Andrew D. Sauter
    • 1
  • Julie P. Harmon
    • 2
    Email author
  1. 1.Nanoliter LLCHendersonUSA
  2. 2.Department of ChemistryUniversity of South FloridaTampa

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