Adding Auxiliary Electrode—An Effective Method for Enhancing Signal‐to‐Noise Ratio in Nanospray Mass Spectrometry

Abstract

A simple arrangement for improving signal‐to‐noise ratio (S/N) in a nanoelectrospray procedure using an auxiliary electrode has been investigated. The auxiliary electrode (aluminium plate in the present experiments) with different size and shape was placed near the home‐made nanoelectrospray tip and various electrical potential was added, which could dramatically disturb nanoelectrospray properties. This arrangement was employed to enhance S/N of tips spraying reserpine solution at different concentrations under the control experimental conditions. The comparison of S/N of nanoelectrospray with and without auxiliary electrode gives an explicit trend that auxiliary electrode could improve sensitivity of nanoelectrospray to at least twofold.

Keywords:

• Nanoelectrospray
• Reserpine
• Mass spectrometry
• Auxiliary electrode

Acknowledgment

The authors are grateful to Dr. Gangqiang Li in Agilent Co. for his helpful discussions.

The research is supported by National Basic Research Priorities Programme (Grant No. 001CB510202) and National Nature Science Foundation (Grant No. 20299030).