Data related to "Seeing the chemistry of biomolecular condensates: in situ mapping of composition and water content"

Here, we introduce Raman spectroscopy coupled with spectral phasor analysis as an in situ, label-free approach to resolve the chemical profiles and molecular concentrations within both the dense and dilute phases of biomolecular condensates. This method outperforms traditional regression and deconvolution approaches, yielding a precise readout of client molecule partitioning. By accounting for contributions of the protein backbone to the Raman spectra of condensates, we assess the signature of "solid-like" hydrogen-bonded water from protein hydration, revealing that most water molecules within condensates retain bulk, "liquid-like" properties.

Finally, using environment-sensitive fluorescent probes, we demonstrate that macromolecular structure and water content—rather than hydrogen bonding alone—drive condensate hydrophobicity; notably, the dense phase remains predominantly water-rich even at low apparent dielectric constants.