S-400 Gel filtration elution profiles of proteins extracted from the mature glue of the slug A. subfuscus, and the effect of different treatments. The solubilizing buffer was 20 mM Tris-Cl (pH 8) alone (A, B), or with 0.5 % Tween (C), 8 M Urea and 0.5% Tween (D), 10 mM EDTA (E) or 1 M NaCl (F). Sample A was sonicated extensively, which heated the sample. Proteins or macromolecular complexes that are several thousand kDa or larger would elute between 41 and 54 mL, horse ferritin (440 kDa) elutes between 64 and 78 mL, BSA (66 kDa) elutes between 70 and 90 mL, and a yellow pigment in the glue elutes between 100 and 120 mL.