Chromatography Forum

When using a phosphate buffer system how frequently should one flush the entire system with water (not only the piston back-chamber) in order to prevent crystalization and wearing of the spare parts?

I either kept the buffer flowing at a slow rate (even in a recycle mode with eluent going back into the mobile phase container) or I flushed the entire path (mobile phase reservoir forward through detector to waste line) with flush solvent made up similarly but without the buffer salts (phosphate) - every time.

Thanks for the reply! So not even the column should be kept in the phosphate buffer...And at the end of the day either recirculate the phosphate or wash the entire system with water. The important issue behind this question are some ghost peaks obtained when injecting buffer through the column. They are somewhat reproductible but abnormal in my opinion.

I either get fat burners for women here at a slow rate (even in a recycle mode with eluent going back into the mobile phase container) or I flushed the entire path (mobile phase reservoir forward through detector to waste line) with flush solvent made up similarly but without the buffer salts (phosphate) - every time.

Every time? Maybe I should be doing that too.

This article from John Dolan's "LC Troubleshooting" series in LC-GC is almost 20 years old, but still very relevant:
http://www.lcresources.com/tsbible/26042008.PDF

Thanks for the reply! So not even the column should be kept in the phosphate buffer...And at the end of the day either recirculate the phosphate or wash the entire system with water.

Not water specifically: similar aqueous-organic mix but NO salts !