#4 How Do You Listen to Your FPLC UV Detector?
Sawtooth UV signals can be an indication of air trapped in your flow cell. You can often chase the bubble out of your system with 1 N NaOH.
Random spikes in a UV trace that coincide with negative conductivity spikes most often indicate presence of air. Recurring instances of these spikes can often be corrected by purging your system with 1 N NaOH.
Signs of pulsation in your gradient may indicate that you are not using the correct size of mixer for your flow rate.
S-shaped conductivity gradient curves often indicate a mismatch between mixer size and flow rate.