Updated FTP location. We determined if the glycolaldehyde (GA)-modified proteins could show an affinity with serum proteins. The mouse serum was incubated with the ligand-coupled beads for 1 h at room temperature. The ligands used were BSA and GA-treated BSA (GA-BSA). The proteins bound to the beads were eluted and separated by SDS-PAGE. Seven unique bands detected in the pull-down with the GA-BSA ligands were processed for tryptic digestion and LC-MS/MS analysis.