Phosphopeptides isolated using TiO2-based medias are typically desalted prior to analysis by LC-MS/MS, typically using a C18 (hydrophobic) micropipette tip. GL-Tip SDB are more hydrophobic than C18 medias and allow retention of phosphopeptides with high yield, allowing more accurate analysis of phosphopeptides species present in the sample. GL-Tip GC retain many more hydrophilic phosphopeptides than does C18; by using a combination of GL-Tip SDB and GC, almost all peptide samples can be desalted without sample losses due to lack of retention. Another highlight of this product is, the operation is very easy-to-use. Phosphopeptide-enriched samples are easily loaded, washed, and eluted using the same centrifuge-based technique used with Phos-TiO spin tips.