1. Adequate flow rate
If your method does not have a predefined flow rate, start with 5mL/min for pre-conditioning. Sample loading can be set to 10-15mL/min on 6mL reversed-phase SPE cartridges and 5-8mL/min on 6mL anion-exchange SPE cartridges. Final elution can be set to 3-5mL/min. These flow rates can be set directly on our SPE systems.
2. Proper SPE cartridge drying
Check that nitrogen supply is turned on and effectively drying the SPE cartridges. Start with 20psi and 2.