SAXS measurements were conducted at room temperature with the use of 0.25% wt. solution of IgG1 in a buffer. The low-resolution envelope structure of IgG1 was determined by Ab-initio reconstruction with the use of the DAMMIN software package of EMBL.
Figure 1 represents the reconstructed structure (top) compared to the high-resolution structure 1IGY obtained by X-ray crystallography  (bottom).
The estimated molecular mass for the reconstructed structure was determined to be 145 kDa compared to 146kDa of the high-resolution structure.
Figure 1. IgG1 structure reconstructed from SAXS solution scattering experiment (top) compared with the 1IGY high-resolution model (bottom) 
 1IGY entry in pdb database (www.pdb.org)