“…Other hydrophilic phases, such as glass, cellulose, and CN-silica, are also used for removing excess reagents. 66,67 High-acetonitrile conditions, typically more than 95%, are useful in capturing picomole amounts of derivatized oligosaccharides on hydrophilic SPE. A recent investigation into the recovery of small sugar chains (i.e., one to four residues) using polyamide matrix (Discovery DPA-6S) suggested that a slightly higher concentration of acetonitrile (97% vs. 95%) enhances recovery.…”