Peptide enrichment by microfluidic electrocapture for online analysis by electrospray mass spectrometry |
| |
Authors: | Vollmer Susanne Astorga-Wells Juan Alvelius Gunvor Bergman Tomas Jörnvall Hans |
| |
Institution: | Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden. |
| |
Abstract: | Identification of peptides from a complex mixture can be difficult because of the wide concentration range and the different ionization efficiencies of peptides during analysis by electrospray ionization (ESI) mass spectrometry (MS). Preconcentration methods are necessary to allow low-abundance and low-intensity peptides to reach the ionization threshold of the mass spectrometer. Here we demonstrate peptide enrichment based on electroimmobilization. Peptides are immobilized without the use of solid support or chemical binding by application of an electric field along a microflow stream in an electrocapture cell. Once enriched/preconcentrated inside the cell, they are released by removal of the electric field and via an interface with an electrospray emitter are submitted to online mass spectrometric analysis. Tandem mass spectrometric analysis of a peptide mixture containing hemoglobin, myoglobin, bovine serum albumin (BSA), and cytochrome c was successful. Amplification factors up to 16-fold were achieved with improvement of the signal-to-noise values for the preconcentrated sample. The limit of detection for one of the preconcentrated peptides was 3.6 fmol. |
| |
Keywords: | Peptide enrichment Preconcentration Microfluidic electrocapture Electrospray ionization (ESI) mass spectrometry (MS) Undersampling Ionization efficiency Peptide identification Signal-to-noise (S/N) ratio Limit of detection (LOD) |
本文献已被 ScienceDirect PubMed 等数据库收录! |