I am testing IgG antibodies, and notice that the formulation buffer peak is eluting at the same time as LMWS peaks, essentially masking them so i cant really quantify LMWS %.

Is there any way to solve this problem?

Mobile Phase/Diluent is PBS pH 7.2, column is 300A 4.6x 300 mm

With isocratic for 16 minutes at 0.3 mL/min(recommended column flow rate)

The formulation buffer that antibody is in contains EDTA, PBS, and ammonium acetate.

Thank you.