High speed capillary zone electrophoresis-mass spectrometry via an electrokinetically pumped sheath flow interface for rapid analysis of amino acids and a protein digest.
While capillary zone electrophoresis (CZE) has been used to produce very rapid and efficient separations, coupling these high-speed separations with mass spectrometry (MS) has been challenging. Now, with much faster and sensitive mass spectrometers, it is possible to take full advantage of the CZE speed and reconstruct the fast migrating peaks. Here are three high-speed CZE-MS analyses via an electrokinetically pumped sheath-flow interface. The first separation demonstrates CZE-ESI-MS of an amino acid mixture with a 2-min separation, >50,000 theoretical plates, low micromolar concentration detection limits, and subfemtomole mass detection limits (LTQ XL mass spectrometer). The second separation with our recently improved third-generation CE-MS interface illustrates a 20 amino acid separation in ∼7min with an average over 200,000 plate counts, and results in almost-baseline resolution of structural isomers, leucine and isoleucine. The third separation is of a BSA digest with a reproducible CZE separation and mass spectrometry detection in 2min. CZE-MS/MS analysis of the BSA digest identified 31 peptides, produced 52% sequence coverage, and generated a peak capacity of ∼40 across the 1-min separation window (Q-Exactive mass spectrometer).
Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
Nicole M
NM
Schiavone
Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
Scott A
SA
Sarver
Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
Liangliang
L
Sun
Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
Roza
R
Wojcik
Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA. Electronic address: ndovichi@nd.edu.
Norman J
NJ
Dovichi
D000596:Amino Acids / Q000032:analysis* / Q000302:isolation & purification; D000818:Animals; D002417:Cattle; D019075:Electrophoresis, Capillary / Q000191:economics / Q000379:methods*; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000191:economics / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000191:economics / Q000379:methods*; D013997:Time Factors
D000596:Amino Acids; D012710:Serum Albumin, Bovine
Amino acids; Capillary zone electrophoresis; Electrokinetically pumped nanospray; High-speed separation; Tandem mass spectrometry; Tryptic digest