Analysis of partitioning of organic compounds and proteins in aqueous polyethylene glycol-sodium sulfate aqueous two-phase systems in terms of solute-solvent interactions.
Partition behavior of nine small organic compounds and six proteins was examined in poly(ethylene glycol)-8000-sodium sulfate aqueous two-phase systems containing 0.5M osmolyte (sorbitol, sucrose, trehalose, TMAO) and poly(ethylene glycol)-10000-sodium sulfate system, all in 0.01M sodium phosphate buffer, pH 6.8. The differences between the solvent properties of the coexisting phases (solvent dipolarity/polarizability, hydrogen bond donor acidity, and hydrogen bond acceptor basicity) were characterized with solvatochromic dyes using the solvatochromic comparison method. Differences between the electrostatic properties of the phases were determined by analysis of partitioning of sodium salts of dinitrophenylated (DNP-) amino acids with aliphatic alkyl side-chain. It was found out that the partition coefficient of all compounds examined (including proteins) may be described in terms of solute-solvent interactions. The results obtained in the study show that solute-solvent interactions of nonionic organic compounds and proteins in polyethylene glycol-sodium sulfate aqueous two-phase system differ from those in polyethylene glycol-dextran system.
IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal; Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia.
Nuno R
NR
da Silva
Analiza, Inc., 3615 Superior Ave., Cleveland, OH 44114, USA; Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia.
Luisa A
LA
Ferreira
Laboratory of Separation and Reaction Engineering, Department of Chemical Engineering, Faculty of Engineering of the University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia.
Pedro P
PP
Madeira
IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal; Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia.
José A
JA
Teixeira
Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia.
Vladimir N
VN
Uversky
Analiza, Inc., 3615 Superior Ave., Cleveland, OH 44114, USA; Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia. Electronic address: bz@analiza.com.
Boris Y
BY
Zaslavsky
D000596:Amino Acids / Q000737:chemistry; D003911:Dextrans / Q000737:chemistry; D006860:Hydrogen Bonding; D011092:Polyethylene Glycols / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D012997:Solvents; D055672:Static Electricity; D013431:Sulfates; D014867:Water
D000596:Amino Acids; D003911:Dextrans; D011506:Proteins; D012997:Solvents; D013431:Sulfates; D014867:Water; C012036:sodium sulfate; D011092:Polyethylene Glycols; C000595216:polyethylene glycol 8000
Aqueous two-phase system; Partitioning; Proteins; Solute–water interactions; Solvatochromic comparison method; Solvent properties