Kinetics of Calcite Nucleation onto Sulfated Chitosan Derivatives and Implications for Water-Polysaccharide Interactions during Crystallization of Sparingly Soluble Salts.

ABSTRACT: Anionic macromolecules are found at sites of CaCO₃ biomineralization in diverse organisms, but their roles in crystallization are not well-understood. We prepared a series of sulfated chitosan derivatives with varied positions and degrees of sulfation, DS(SO₃ ^-), and measured calcite nucleation rate onto these materials. Fitting the classical nucleation theory model to the kinetic data reveals the interfacial free energy of the calcite-polysaccharide-solution system, γ_net, is lowest for nonsulfated controls and increases with DS(SO₃ ^-). The kinetic prefactor also increases with DS(SO₃ ^-). Simulations of Ca²⁺-H₂O-chitosan systems show greater water structuring around sulfate groups

SUBMITTER: Knight BM 

PROVIDER: S-EPMC11311137 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature