Simple Sodium Dodecyl Sulfate-Assisted Sample Preparation Method for LC-MS-Based Proteomics Applications

Sodium dodecyl sulfate (SDS) is one of the most popular
laboratory
reagents used for biological sample extraction; however, the presence
of this reagent in samples challenges LC-MS-based proteomics analyses
because it can interfere with reversed-phase LC separations and electrospray
ionization. This study reports a simple SDS-assisted proteomics sample
preparation method facilitated by a novel peptide-level SDS removal
step. In an initial demonstration, SDS was effectively (>99.9%)
removed
from peptide samples through ion substitution-mediated DS– precipitation using potassium chloride (KCl), and excellent peptide
recovery (>95%) was observed for <20 μg of peptides.
Further experiments demonstrated the compatibility of this protocol
with LC-MS/MS analyses. The resulting proteome coverage obtained for
both mammalian tissues and bacterial samples was comparable to or
better than that obtained for the same sample types prepared using
standard proteomics preparation methods and analyzed using LC-MS/MS.
These results suggest the SDS-assisted protocol is a practical, simple,
and broadly applicable proteomics sample processing method, which
can be particularly useful when dealing with samples difficult to
solubilize by other methods.