Hydrogen Bond Arrangement Is Shown to Differ in Coexisting Phases of Aqueous Two-Phase Systems

Analysis by attenuated total reflection-Fourier transform infrared spectroscopy shows that each coexisting phase in aqueous two-phase systems has a different arrangement of hydrogen bonds. Specific arrangements vary for systems formed by different solutes. The hydrogen bond arrangement is shown to correlate with differences in hydrophobic and electrostatic properties of the different phases of five specific systems, four formed by two polymers and one by a single polymer and salt. The results presented here suggest that the arrangement of hydrogen bonds may be an important factor in phase separation.

Automated summary

Analysis using attenuated total reflection-Fourier transform infrared spectroscopy revealed that each coexisting phase in aqueous two-phase systems has a unique arrangement of hydrogen bonds. The specific arrangements vary depending on the solutes present in the system, and are correlated with the differences in hydrophobic and electrostatic properties of the phases in the systems studied. This suggests that the arrangement of hydrogen bonds may play a significant role in phase separation.