Synchrotron SAXS data from solutions of IMP-1 saRNA encoding NSP1-4 of VEEV and the spike glycoprotein of SARS-CoV-2 in 5 mM sodium citrate formulation buffer, pH 6.4 were collected on the B21 beam line at the Diamond Light Source (Didcot, UK) using a Eiger 4M detector at a sample-detector distance of 4.0 m and at a wavelength of λ = 0.1 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). In-line size-exclusion chromatography (SEC) SAS was employed. The SEC parameters were as follows: A 35.00 μl sample at 2.0 mg/ml was injected at a 0.16 ml/min flow rate onto a Shodex KW400 series column at 20°C. 640 successive 3 second frames were collected. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.