Online SEC/MS Analysis of Proteins on Unix™ SEC-300: Effect of Mobile Phase Modifier
CONDITIONS
column
Unix SEC-300, 30 cm x 4.6 mm I.D., 1.8 μm particles (Z777302)
mobile phase
[A] modifier (as indicated):[B] 100 mM ammonium acetate, adjusted to pH 7.0 with ammonium hydroxide, 90:10; A:B
flow rate
0.3 mL/min
pressure
2170 psi (no modifier); 2940 psi (isopropanol); 2600 psi (methanol) (150 bar (no modifier); 203 bar (isopropanol); 179 bar (methanol))
column temp.
35 °C
detector
UV, 215 nm
injection
1.0 μL
sample
protein mix, 100 μg/mL, 100 mM ammonium acetate, pH 7.0 with ammonium hydroxide
Description
Analysis Note
This application demonstrates the importance of the inclusion of an organic modifier in online SEC/MS. The organic modifier minimizes any interactions between the analytes and free silanols on the silica stationary phase. Improved efficiency and resolution of the protein analytes were observed when an organic modifier was included in the mobile phase, with methanol yielding the most improvement.
Legal Information
Unix is a trademark of Sepax Technologies