Since Cogent TYPE-C columns can be used in Reverse Phase or Normal Phase modes, what do you suggest to switch them since these solvent systems are not miscible?
Just as a reminder, all Cogent Bidendate C18 and C8 columns are filled with water containing solvents during shipping. To start work in Normal Phase Mode, a simple switching procedure is recommended. A simple 30 minute procedure allows switching from one mode to another. Procedure: A moving from Reverse Phase to Normal Phase HPLC; pump 100% methanol for 15 minutes at 1 mL/min. flow rate, followed by 15 minutes 100% methylene chloride. The column is ready to be equilibrated with mobile phase for NP-HPLC. B moving from Normal Phase to Reverse Phase HPLC; pump 100% methylene chloride for 15 minutes at 1 mL/min. flow rate, followed by 15 minutes 100% methanol. The column is ready to be equilibrated with mobile phase for RP-HPLC. 25. When I run gradients on my HPLC and switch from one gradient to another, my baseline shows as negative. If I auto zero, it becomes positive for the remainder of the run but when I start again, it is negative. What can you suggest? Negative baselines in gradient
Related Questions
- Since Cogent TYPE-C columns can be used in Reverse Phase or Normal Phase modes, what do you suggest to switch them since these solvent systems are not miscible?
- What characteristics of a normal fault and reverse fault can be used to easily tell them apart?
- Why acetonitrile and methanol are most commonly used solvent for reverse phase HPLC?
