Synchrotron SAXS data from solutions of 20 nm polystyrene beads separated using asymmetric flow field flow fractionation (AF4) in water/detergent solution (0.0125 % (v/v) NovaChem), pH 7 were collected on the EMBL P12 beam line at PETRA III (DESY; Hamburg, Germany) using a Pilatus 6M detector at a sample-detector distance of 6 m and at a wavelength of λ = 0.12 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). AF4 separation was performed at 20°C using a detector flow rate of 0.5 mL/min with a starting cross flow rate of 2 mL/min with an exponential decay. 300 µL of a polystyrene bead mixture (0.44% PS 20 nm + 1.1 % PS 100 nm) were injected. 2100 successive 1 second SAXS data frames were collected through the entire AF4 elution (35 min), where 30 sample data frames were selected through the second elution peak corresponding to the PS 20 nm fraction. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.
Note. The expected MW calculated from the from the atomic composition of the beads is unknown.