Molecular Weight in Physiological state
Molecular weight measurements require absolute intensity measurement of scattering. With Xenocs SAXS equipment, this is possible without the need for intensity calibration.
Particle Size in Physiological state
Particle size measurement is the diameter of globular shaped particles and the related number- or volume-weighted size distribution. The quantitative analysis in terms of volume fraction or mass concentration is possible due to scattering intensities being normalized to absolute units.
“By tailoring the KinExA to each studied antigen, we obtained apparent equilibrium dissociation constants (Kd) value spanning six orders of magnitude, from approximately 100fm to 100nM”
“In addition to the simplicity of the approach, the method provides a true measure of the affinity/ avidity of the antibody to the native form of cell-surface-expressed targets, including antigens that cannot be produced in soluble forms, and to unknown cell surface antigens.”