Why is my 4.6-mm ID SEC and GPC column giving poor peak shape and broad peaks on an HPLC system that is normally successful with 7.8-mm ID SEC and GPC columns? - WKB48380

ENVIRONMENT

• SEC and GPC columns

ANSWER

The system dispersion or bandspread influences peak shape and is too large for the column size.  

ADDITIONAL INFORMATION

SEC and GPC separation mechanisms are slow-flow techniques in which system bandspread has a large influence on peak shape and resolution. The separation occurs in the interstitial spaces of the column. When system bandspread is too high for the column dimension, it affects the peak width as it travels through the instrument into the column. 

Systems must be optimized to reduce system dispersion or bandspread in order to run 4.6-mm ID columns.   

For additional information, see ACQUITY UPLC Protein BEH SEC Columns and Standards Care and Use Manual, section II, "Configuring your ACQUITY UPLC for use in Protein SEC separations and optimal separation performance".

See also Considerations When SEC Separated Components Tail and/or Resolution Decreases.