The Chromatogram Series: BSA

par Ulf Nobbmann, Thursday, 8th August 2013

Here is a simple chromatogram of Bovine Serum Albumin (BSA). Yes, BSA is ubiquitous…and this one came from Sigma. The run conditions are detailed in the table.

Edit
Run Buffer PBS
Flow Rate [mL/min] 0.800
Column Set P2500 + P3000
Column Temp (°C) 30.0
Injection volume μL 80.0
Concentration [mg/mL] 6.96
Mw Weight Average [Da] 65,001
Sample dn/dc [mL/g] 0.185
Sample IV [dL/g] 0.0311
Bovine Serum Albumin chromatogram, displaying signal from RI, Viscometer, RALS and LALS light scattering
Chromatogram of BSA: Refractive Index (RI), Viscosity, Right Angle Light Scattering (RALS) and Low Angle Light Scattering (LALS) signals versus elution volume.

The sample shows excellent separation between the monomer and dimer peaks. Calculated molecular weights are within 3% of the expected values and are stable across the width of the peaks showing monodisperse populations are eluting.
Additionally, the 7º (LALS) and 90º (RALS) light scattering measurements overlay demonstrating that at these molecular sizes, only one angle is necessary for highly accurate and reproducible molecular weight measurements.

Previously

If you have any questions, please email me at ulf.nobbmann@malvern.com. Thanks!