Ultra-low Flow Range Reduces Ion Suppression and Increases MS Assay Sensitivity

ORANGE COUNTY, CALIF. – (June 2, 2011) – The CESI 8000 High-Performance Separation-ESI Module with OptiMS Technology from Beckman Coulter, Inc. consists of the first commercial CESI sprayer combined with new capillary electrophoresis instrumentation specifically designed for mass spectrometry (MS). This gives researchers a robust, high-sensitivity interface of capillary electrophoresis (CE) with MS, while providing a broad range of analyte coverage complementary to LC-MS and GC-MS.

OptiMS Technology integrates an intrinsically low flow CE separation (as low as 10 nL/min.) with electrospray ionization (ESI) in a single, dynamic process that takes place within a capillary. The new process is referred to as CESI, reflecting the combination. To achieve CESI, the distal end of the capillary is porous to ion flow, allowing the electrophoresis circuit to be bridged and ESI to be initiated within the same device.

CESI-MS is capable of generating separations of peptides with a high peak capacity (>320), allowing the analysis of very complex samples at the proteome level. The ultra-low flow rates used by CE effectively reduce ion suppression and make it possible to detect post-translational modifications (PTMs) like phosphorylation and sialylation, which typically hamper efficient ionization. High-separation efficiency and sensitivity permit the detection of peptides present in low abundance at concentrations in the picoMolar range. The selectivity of CE in front-end separation further enables the characterization of intact proteins, their isoforms, cleaved fragments and complexes.

CESI 8000 with OptiMS Technology from Beckman Coulter also provides fast and efficient separations of drugs, drug metabolites, organic acids, amino acids, low molecular weight amines, peptides, nucleic acids and nucleosides. Molecules often missed or altogether undetectable by technologies like reversed phase LC-MS, now become visible with CESI 8000.

“The CESI 8000 was developed in collaboration with mass spectrometry researchers who work in a variety of applications and who sought to expand the range of analytes detected while improving overall assay sensitivity,” noted Jeff Chapman, director of Beckman Coulter Discovery Products. “The result is a front-end separation system that generates data complementary to HPLC and provides scientists with important, previously unavailable information.”

Easy switching between LC-ESI-MS and CESI-MS allows the addition of CESI to existing workflows. The CESI 8000 is installed on a height-adjustable, gear-driven portable lab bench so it can be rapidly set to the proper height of a mass spectrometer. Plug-and-spray adapters are available for top brand nanosources.