The addition of Tween 20 can modify lignin surface properties, altering its hydrophobicity, hydrogen bonding ability, and surface charges, thereby reducing the non-productive adsorption of proteins^[1].

When Tween 20 (0.35%-0.7% w/w) is added to 0.05 mol/L of phosphate buffer at pH 6.5, it dramatically increases the apparent solubility of the drug from 0.8 μg/ml to 353 μg/ml, while its effect in lower pH or in water is much smaller (20 μg/ml in pH 4.5). The increased concentration of phosphate salts (0.2 mol/l) at pH 6.5 in the presence of 0.7% of Tween 20 results in a further increase of candesartan cilexetil solubility to 620 μg/ml^[2].