In-line desalting of proteins from buffer and synthetic urine solution prior to ESI-MS analysis via a capillary-channeled polymer fiber microcolumn.
PMID 23463546 · Journal of the American Society for Mass Spectrometry · 2013 · DOI 10.1007/s13361-013-0593-1
Authors: Carolyn Q Burdette; R Kenneth Marcus
Abstract
Presented here is a novel in-line solid phase extraction (SPE) method utilizing a capillary-channeled polymer (C-CP) fiber microcolumn prior to introduction to an electrospray ionization (ESI) source. The high permeability of the microcolumn allows for operation under syringe pump or HPLC driven flow, ultimately providing greater mass spectral clarity and accurate molecular weight determinations for different protein/buffer combinations. Studies presented here focus on the desalting of several target proteins from a standard phosphate buffered saline (PBS) matrix and a synthetic urine solution prior to ESI-MS determinations. In every case, responses for μM-level proteins in PBS improve from the situation of not permitting molecular weight determinations to values that are precise to better than ±10 Da, without internal standards, with relative improvements in the signal-to-background ratios (S/B) on the order of 3,000×. De-salting of a myoglobin-spiked (12 μM) synthetic urine results in equally-improved spectral quality.
Models, Chemical; Molecular Weight; Permeability; Polymers; Proteins; Sodium Chloride; Solid Phase Extraction; Spectrometry, Mass, Electrospray Ionization
Cite
Carolyn Q Burdette; R Kenneth Marcus. In-line desalting of proteins from buffer and synthetic urine solution prior to ESI-MS analysis via a capillary-channeled polymer fiber microcolumn. Journal of the American Society for Mass Spectrometry (2013). PMID 23463546. DOI 10.1007/s13361-013-0593-1.