Omnisec software v5

Size exclusion chromatography experiments were performed with a HPLC pump (LC10AD, Shimadzu) coupled to an autosampler (Viscotek VE 2001, Malvern Panalytical) and a multi-detector system recording light scattering (RALS/LALS) intrinsic viscosity and refractive index signals (Viscotek TDA305, Malvern Panalytical). The HPLC SEC column (BioSec5 500 Å, 5 μm, 7.8 mm ID × 300 mm, void volume ∼6 mL, total volume ∼ 12.5 mL, Agilent) was equipped with a post-column nylon filter (0.22 μm). The column was equilibrated with PBS (pH 6.8) supplemented with sodium azide 0.02%. The flow rate and the temperature were 0.35 mL/min and 30°C respectively. Data were processed with the OmniSEC software (v5.12, Malvern Panalytical). The calibration procedure was done with BSA (Sigma) and cross-validation was performed with β-lactoglobulin (Sigma). The refractometer was used as the concentration detector and the refractive index increment value (dn/dc) used to determine the molecular weight was 0.185 mL/g. Samples were diafiltered in the aforementioned buffer and filtered through a 0.22 μm PES-filter just before injection.

SEC experiments were performed with a HPLC pump (LC10AD, Shimadzu, Noisiel, France) coupled to an autosampler (Autosampler VE 2001, Malvern Panalytical, Palaiseau, France) and a multi-detector system recording UV, light scattering (RALS/LALS) intrinsic viscosity and refractive index signals (Viscotek TDA305, Malvern Panalytical, Palaiseau, France). One SEC column (A6000M, 10 or 13 μm, 8 mm ID × 300 mm, void volume ~6 mL, total volume ~12.5 mL, Malvern Panalytical, Palaiseau, France) was equipped with a post-column nylon filter (0.22 µm). The column was equilibrated with NaNO₃ 0.15 M, NaN₃ 0.02% and EDTA 0.01 M in ultrapure water. The flowrate was 0.7 mL·min⁻¹ and the temperature was 30 °C. Data were processed with the Omnisec software (v5.12, Malvern Panalytical, Palaiseau, France). The calibration procedure was performed with bovine serum albumin, and cross-validations were performed with the PEO24k and Dextran standards. The refractometer was used as the concentration detector and the refractive index increment value (dn/dc) used to determine the molecular weight (Mw) was 0.150 mL/g [16 (link)]. Alginate samples were solubilized in the aforementioned buffer at 2 g·L⁻¹ and filtered through a 0.22 µm PES filter shortly before injection (injection volume: 100 µL).