Optimization of solid phase microextraction - capillary zone electrophoresis - mass spectrometry for high sensitivity protein identification

Electrophoresis. 1998 Oct;19(13):2338-47. doi: 10.1002/elps.1150191314.


We have previously described the use of a solid phase extraction (SPE) - capillary zone electrophoresis (CZE) - tandem mass spectrometry (MS/MS) system for protein analysis at the low femtomole to subfemtomole level. Here we describe the systematic optimization of a number of parameters which facilitate the use of the SPE-CZE-MS/MS system and further enhance its performance. Specifically, we describe a robust SPE cartridge design which can be assembled without the use of glue, the evaluation of procedures to chemically modify the inner wall of the fused-silica capillaries used in the system to improve separation and reproducibility, and the comparison of different reverse-phase (RP) resins used for the SPE cartridge. We also explored the effects of transient isotachophoresis with respect to system performance and compatibility with different fused-silica surface coatings, the RP resins used, and MS/MS. The enhanced performance of the optimized system is demonstrated by the analysis of calibrated tryptic digests of bovine serum albumin (BSA).

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acetonitriles
  • Electrolytes
  • Electrophoresis, Capillary / instrumentation
  • Electrophoresis, Capillary / methods*
  • Hydrogen-Ion Concentration
  • Mass Spectrometry / methods*
  • Peptide Fragments / analysis
  • Peptide Fragments / metabolism
  • Proteins / analysis*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Serum Albumin, Bovine / analysis
  • Serum Albumin, Bovine / metabolism
  • Trypsin


  • Acetonitriles
  • Electrolytes
  • Peptide Fragments
  • Proteins
  • Serum Albumin, Bovine
  • Trypsin
  • acetonitrile