Cooperativity between various types of polar solute-solvent interactions in aqueous media.

Partition coefficients of seven low molecular weight compounds were measured in multiple aqueous two-phase systems (ATPSs) formed by pairs of different polymers. The ionic composition of each ATPS was varied to include 0.01M sodium phosphate buffer (NaPB), pH 7.

Study of organic compounds-water interactions by partition in aqueous two-phase systems.

Partition coefficients of fourteen organic compounds were determined in 10 or 20 different polymer/polymer aqueous two-phase systems (ATPS) all at physiological pH (0.15M NaCl in 0.01M phosphate buffer, pH 7.

Amino acid/water interactions study: a new amino acid scale.

Partition ratios of 8 free l-amino acids (Gln, Glu, His, Lys, Met, Ser, Thr, and Tyr) were measured in 10 different polymer/polymer aqueous two-phase systems containing 0.15 M NaCl in 0.01 M phosphate buffer, pH 7.

Analysis of amino acid-water interactions by partitioning in aqueous two-phase systems. I--amino acids with non-polar side-chains.

Partition ratios of 10 L-amino acids with non-polar side chains (Gly, Ala, Val, nor-Val, Ile, Leu, nor-Leu, Phe, Trp and Pro) were measured in ten different polymer/polymer aqueous two-phase systems (ATPS) containing 0.15 M NaCl in 0.01 M phosphate buffer, pH 7.

Solvatochromic relationship: prediction of distribution of ionic solutes in aqueous two-phase systems.

Partition ratios of several ionic compounds in 20 different polymer/polymer aqueous two-phase systems (ATPS) containing 0.15 M NaCl in 0.01 M phosphate buffer, pH 7.

Salt effects on solvent features of coexisting phases in aqueous polymer/polymer two-phase systems.

The solvatochromic parameters characterizing the solvent dipolarity/polarizability (π*), solvent hydrogen-bond donor acidity (α), and solvent hydrogen-bond acceptor basicity (β) of aqueous media were measured in the coexisting phases of aqueous Dextran-Ficoll, Dextran-Ucon, Dextran-PEG, PEG-Ucon, Ficoll-Ucon, and Ficoll-PEG two-phase systems (ATPS). Ionic composition of each ATPS included 0.15M KCl, 0.

Optimization of a flow injection analysis system for tartaric acid determination in wines.

The objective of this work is the development and optimization of a method for tartaric acid analysis in wines that does not require any sample pre-treatment and with adequate accuracy. A flow injection analysis manifold with three channels, using a dialysis unit to eliminate sample matrix interferences and to accomplish on-line dilution, is proposed for the spectrophotometrical determination of tartaric acid in wines making use of its reaction with vanadate. The proposed method is fast, accurate, simple, economic and does not require any sample pre-treatment.