Long-lived metallized tips for nanoliter electrospray mass spectrometry
G A Valaskovic1, F W McLafferty
1Chemistry Department, Cornell University, Ithaca, New York, USA.
Journal of the American Society for Mass Spectrometry
|November 9, 2013
Summary
A new SiO x coating technique enhances the stability of gold electrodes used in sheathless electrospray mass spectrometry. This improves tip lifetime for analyzing proteins by mass spectrometry.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
- Surface Science
Background:
- Sheathless electrospray coupled with Fourier-transform mass spectrometry enables high-resolution analysis of proteins.
- The mechanical instability of gold film electrodes limits tip lifetime to 15-30 minutes.
- This limitation hinders the practical application of this advanced analytical technique.
Purpose of the Study:
- To develop a method for improving the mechanical stability and longevity of gold film electrodes for electrospray ionization.
- To enhance the operational stability of electrospray tips for mass spectrometry applications.
Main Methods:
- Fabrication of thin gold film electrodes (35-100 nm).
- Application of a silicon oxide (SiO x) coating to the gold electrodes.
- Testing electrode stability under electrospray conditions, including voltage interruptions and arcs.
Main Results:
- The SiO x coating significantly improved electrode mechanical stability.
- A steady ion current (±10 pA) was maintained for 1-2 hours.
- The coated electrodes demonstrated resilience to arcs and electrospray voltage interruptions.
Conclusions:
- SiO x coating is an effective strategy to enhance the durability of gold electrodes for sheathless electrospray mass spectrometry.
- This advancement extends tip operational lifetime, making high-resolution protein analysis more robust and reliable.
- The improved stability facilitates longer analytical runs and broader applicability of the technique.
