What variables can affect accuracy of sedimentation and diffusion coefficient calculations?
- Location between the two menisci (i.e., it must be properly selected)
- Density of the solvent
- Temperature (affects viscosity)
- Concentration dependency (pure, non-associating solutes show a decrease in sedimentation coefficient with an increase in concentration)
- Radial dilution due to sector shapes
- Boundary analysis (concentration and shape)
- Speed dependence (sedimentation coefficient may increase with speed increase, and result in solute aggregation)
- Primary electrostatic charge of solute and solvent
- Association reactions that might occur between molecules as molecular weight increases