Precipitation of ACC in liposomes-a model for biomineralization in confined volumes

Journal Article · Thu Jan 10 00:00:00 EST 2013 · Faraday Discussions

DOI:https://doi.org/10.1039/C2FD20088K· OSTI ID:1054365

Tester, Chantel C; Wu, Ching-Hsuan; Weigand, Steven; Joester, Derk ^[1]

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1. NWU

Biomineralizing organisms frequently precipitate minerals in small phospholipid bilayer-delineated compartments. We have established an in vitro model system to investigate the effect of confinement in attoliter to femtoliter volumes on the precipitation of calcium carbonate. In particular, we analyze the growth and stabilization of liposome-encapsulated amorphous calcium carbonate (ACC) nanoparticles using a combination of in situ techniques, cryo-transmission electron microscopy (Cryo-TEM), and small angle X-ray scattering (SAXS). Herein, we discuss ACC nanoparticle growth rate as a function of liposome size, carbon dioxide flux across the liposome membrane, pH, and osmotic pressure. Based on these experiments, we argue that the stabilization of ACC nanoparticles in liposomes is a consequence of a low nucleation rate (high activation barrier) of crystalline polymorphs of calcium carbonate.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
• Sponsoring Organization: NSFUNIVERSITY
• OSTI ID: 1054365
• Journal Information: Faraday Discussions, Vol. 159, Issue 2012; ISSN 1359-6640
• Publisher: Royal Society of Chemistry
• Country of Publication: United States
• Language: ENGLISH