Suggested Procedure:

A – Changing from Reversed Phase to Normal Phase HPLC; pump 100% methanol for 15 minutes at 1 mL / minute flow rate, followed by 15 minutes 100% methylene chloride. The column is ready to be equilibrated with mobile phase for NP HPLC.

B – Changing from Normal Phase to Reverses Phase HPLC; pump 100% methylene chloride for 15 minutes at 1 mL / minute flow rate, followed by 15 minutes 100% methanol. The column is ready to be equilibrated with mobile phase for RP-HPLC.

A simple 30 minute procedure allows switching from one mode to another.