Bindley Bioscience Center

Solid Phase Extraction (SPE)

General SPE methods:

Waters Oasis HLB (reversed-phase for acids, bases, and neutrals):

1. Condition 1cc column with 1ml MeOH, 1ml water
2. Equilibrate with 1ml 10:89:1 MeOH:water:HOAc
3. Load sample in same buffer (1ml T.V.)
4. Wash column with 1 ml 10:89:1 MeOH:water:HOAc
5. Elute column with 1 ml of 80:19:1 MeOH:water:HOAc or 99:1 MeOH:HOAc

Waters Oasis MCX (reversed-phase and cation exchange for bases):

1. Condition column with 1 ml MeOH
2. Equilibrate with 1 ml water
3. Load sample in acidified solution diluted with water*
4. Wash sample with 1 ml 2% Formic acid in water (0.1N HCl)
5. Wash sample with 1 ml MeOH or acetonitrile
6. Elute sample with 1 ml 5% NH4OH in MeOH

Waters Oasis WCX (reversed-phase and weak cation exchange for strong bases):

1. Condition column with 1 ml MeOH
2. Equilibrate column with 1 ml water
3. Load sample in basic solution, diluted with water*
4. Wash with 5% NH4OH in water
5. Wash with MeOH
6. Elute with 2-5% Formic acid in MeOH

Strata X (reversed-phase for acids, bases, and neutrals):

1. Condition column with 1 ml MeOH
2. Equilibrate column with 1 ml water
3. Load diluted sample (5-60%) MeOH in water
4. Wash for same % MeOH solution as used to load sample
5. Elute with 50:50 MeOH:ACN solution

*To make solutions for diluting sample to be loaded onto ion exchange columns, Waters recommends preparing solution by adding either 40 µl of concentrated H3PO4 or 40 µl of NH4OH to 1 ml of water. Dilute sample 1:1 with acidified or basified water.