Ion Exchange SPE
Ion exchange sorbents separate analytes based on electrostatic interactions between the analyte of interest and the positively charged groups on the stationary phase. For ion exchange to occur, both the stationary phase and sample must be at a pH where both are charged.
Read more about this topic: Solid Phase Extraction
Famous quotes containing the word exchange:
“To coöperate in the highest as well as the lowest sense, means to get our living together. I heard it proposed lately that two young men should travel together over the world, the one without money, earning his means as he went, before the mast and behind the plow, the other carrying a bill of exchange in his pocket. It was easy to see that they could not long be companions or coöperate, since one would not operate at all. They would part at the first interesting crisis in their adventures.”
—Henry David Thoreau (1817–1862)