Size-exclusion chromatography and dynamic light scattering in tandem allow more accurate characterization of viral complexes formed with b12 IgA. Virus incubated with b12 dIgA was separated over a size exclusion column and followed by particle detection by (A) infrared, (B) ultraviolet, and (C) DLS detection. Size was determined for each peak eluted from the SEC system and the % of signal intensity corresponding to complex size is shown. Two peaks were detected with dIgA preparations, eluted at (D) 21.5 and (E) 23 minutes, measuring 310 nm and 180 nm, respectively. Experiments were performed in triplicate. Results shown are from one representative experiment.