Optimization of capillary electrophoretic-electrospray ionization-mass spectrometric analysis of catecholamines

Katariina Vuorensola, Juha Kokkonen, Heli Sirén (Corresponding Author), Raimo A. Ketola

Research output: Contribution to journalArticleScientificpeer-review

69 Citations (Scopus)

Abstract

The capillary electrophoretic‐mass spectrometric analysis (CE‐MS) of catecholamines was optimized with coaxial sheath flow interface and electrospray ionization (ESI). The parameters studied included the sheath liquid composition and its flow rate, separation conditions in ammonium acetate buffer together with the ESI and cone voltages as mass spectrometric parameters. In addition, the effect of ESI voltage on injection as well as the siphoning effect were considered. The optimized conditions were a sheath liquid composition of methanol‐water (80:20 v/v) with 0.5% acetic acid, with a flow rate of 6 νL/min. The capillary electrophoretic separation parameters were optimized with 50 mM ammonium acetate buffer, pH 4.0, to +25 kV separation voltage together with a pressure of 0.1 psi. The most intensive signals were obtained with an ESI voltage of +4.0 kV and a cone voltage of +20 V. The nonactive ESI voltage during injection as well as avoidance of the siphoning effect increased the sensitivity of the MS detection considerably. The use of ammonium hydroxide as the CE capillary conditioning solution instead of sodium hydroxide did not affect the CE-MS performance, but allowed the conditioning of the capillary between analyses to be performed in the MS without contaminating the ion source.
Original languageEnglish
Pages (from-to)4347-4354
JournalElectrophoresis
Volume22
Issue number20
DOIs
Publication statusPublished - 2001
MoE publication typeA1 Journal article-refereed

Fingerprint Dive into the research topics of 'Optimization of capillary electrophoretic-electrospray ionization-mass spectrometric analysis of catecholamines'. Together they form a unique fingerprint.

  • Cite this