title: Effects of osmolytes on solvent features of water in aqueous solutions.
abstract: The solvatochromic solvent features of water (dipolarity/polarizability, π*, hydrogen bond donor acidity, α, and hydrogen bond acceptor basicity, β) of water have been determined in aqueous solutions of erythritol, glucose, inositol, sarcosine, xylitol and urea with concentrations from 0 to ~3 M and higher. The concentration effects of the osmolytes on the solvent features of water were characterized and compared with those reported previously for sorbitol, sucrose, trimethylamine N-oxide (TMAO), and trehalose. The solvent features of water in solutions of all osmolytes except TMAO and sarcosine were established to be linearly interrelated. It is shown that the concentration effects of essentially all nonionic osmolytes depend on osmolytes' lipophilicity, molecular polarizability, and polar surface area. It is demonstrated that solubility of various compounds in aqueous solutions of glucose, sucrose, sorbitol, and urea of varied concentrations may be described in terms of solvent dipolarity/polarizability of water in these solutions. Surface tension of aqueous solutions of sucrose and sorbitol may also be described in the same terms. The relative permittivity of aqueous solutions of glucose and sucrose may be described in terms of the solvent hydrogen bond donor acidity of water. It is suggested that the effects of nonionic osmolytes on behavior of proteins and nucleic acids in aqueous media may be considered in terms of the altered solvent features of water instead of "nano-molecular crowding" effect.
authors.affiliation: a Cleveland Diagnostics , 3615 Superior Ave., Suite 4407B, Cleveland , OH 44114 , USA.
authors.forename: Luisa A
authors.initials: LA
authors.lastname: Ferreira
authors.affiliation: b Department of Molecular Medicine and Byrd Alzheimer's Research Institute , Morsani College of Medicine, University of South Florida , Tampa , FL 33612 , USA.
authors.forename: Leonid
authors.initials: L
authors.lastname: Breydo
authors.affiliation: c Department of Chemistry , Philipps University , Marburg , Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Reichardt
authors.affiliation: b Department of Molecular Medicine and Byrd Alzheimer's Research Institute , Morsani College of Medicine, University of South Florida , Tampa , FL 33612 , USA.|d Laboratory of Structural Dynamics, Stability and Folding of Proteins , Institute of Cytology, Russian Academy of Sciences , St. Petersburg , Russia.
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Uversky
authors.affiliation: a Cleveland Diagnostics , 3615 Superior Ave., Suite 4407B, Cleveland , OH 44114 , USA.
authors.forename: Boris Y
authors.initials: BY
authors.lastname: Zaslavsky
mesh_terms: D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D009995:Osmosis; D012995:Solubility; D012996:Solutions / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D013500:Surface Tension; D014867:Water / Q000737:chemistry*
chemical_list: D012996:Solutions; D012997:Solvents; D014867:Water
keywords: molecular crowding; osmolytes; relative permittivity; solubility; solvent polarity; surface tension