Mechanism of dye solubilization and de-aggregation by urea

James M Perry, Yu Nagai Kanasaki, Peter Borislavov Karadakov, Seishi Shimizu

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Urea is an effective solubilizer for dyes with low aqueous solubility. To establish, at a molecular level, the reason behind the action of urea as an effective solubilizer, we employ a rigorous statistical thermodynamics approach based on the Kirkwood-Buff theory of solutions. We show that (i) contrary to the classical hypothesis on “water structure breaking”, the effect of urea on dye hydration makes a minor contribution to solubilization; (ii) the driving force of solubilization is the accumulation of urea around hydrophobic dye molecules.
Original languageEnglish
Article number109530
Publication statusPublished - 4 Jun 2021

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