A bicarbonate-rich liquid condensed phase in non-saturated solutions in the absence of divalent cations

Mark A Bewernitz; Matthew Ginder-Vogel; Stephan E Wolf; Jong Seto; Brent R Constantz

doi:10.3389/fbioe.2024.1382047

A bicarbonate-rich liquid condensed phase in non-saturated solutions in the absence of divalent cations

Front Bioeng Biotechnol. 2024 Apr 30:12:1382047. doi: 10.3389/fbioe.2024.1382047. eCollection 2024.

Authors

Mark A Bewernitz¹, Matthew Ginder-Vogel², Stephan E Wolf^{3

4}, Jong Seto⁵, Brent R Constantz^{1

6}

Affiliations

¹ Physical Sciences Department, College of Arts and Sciences, Embry-Riddle Aeronautical University, Daytona Beach, FL, United States.
² Environmental Chemistry and Technology Program, Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI, United States.
³ Department of Materials Science and Engineering, Institute of Glass and Ceramics, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany.
⁴ Interdisciplinary Center for Functional Particle Systems (FPS), Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.
⁵ Center for Biological Physics and School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, AZ, United States.
⁶ Blue Planet, Ltd., Los Gatos, CA, United States.

Abstract

Bicarbonate (HCO₃ ^-) and sodium (Na⁺)-containing solutions contain droplets of a separate, bicarbonate-rich liquid condensed phase (LCP) that have higher concentrations of HCO₃ ^- relative to the bulk solution in which they reside. The existence and composition of the LCP droplets has been investigated by nanoparticle tracking analysis, nuclear magnetic resonance spectroscopy, refractive index measurements and X-ray pair distribution function analysis. The bicarbonate-rich LCP species is a previously unaccounted-for, ionic phenomenon which occurs even in solutions with solely monovalent cations. Its existence requires re-evaluation of models used to describe and model aqueous solution physicochemistry, especially those used to describe and model carbonate mineral formation.

Keywords: bicarbonate; biomineralization; liquid condensed phase; nanoparticle tracking analysis; pair distribution function.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. The authors declare that this study received funding from Blue Planet Limited; a carbon-sequestration company. The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article, or the decision to submit it for publication.