Synthesis of Latex Particles with Biomolecules on the Surfaces by RAFT Emulsion Polymerization and Surface Biomineralization

Biomineralization is an effective approach for the fabrication of structural materials with hierarchical architectures. In this research, surface biomineralization on latex particles synthesized by reversible addition–fragmentation chain transfer (RAFT) mediated emulsion polymerization is reported. Two biomacromolecular chain transfer agents (biomacro-CTAs), one with pendant glutathione (GSH) and the other with GSH and bovine serum albumin (GSH/BSA), were synthesized by RAFT polymerization and subsequent thiol–disulfide exchange reactions. Core–shell latex particles with poly(n-butyl methacrylate) (PnBMA) cores and GSH (or GSH/BSA) shells were prepared by biomacro-CTAs mediated RAFT emulsion polymerizations. The latex particles were analyzed by transmission electron microscopy (TEM), dynamic light scattering (DLS), and ξ-potential analysis. Surface biomineralization of the biomolecules with CaCO3 was performed, and hybrid particles with inorganic layers were fabricated. The inorganic layer thickness and the inorganic component weight percentage increase with an increase in the content of Ca2+ used in the biomineralization. After the formation of the minerals on the latex particles, nanosized organic phases exist inside the continuous inorganic layers due to the organic–inorganic phase separation. Polymer chains and biomolecules are included in the organic phases. The organic phases can be used as nanosized channels in the adsorption of organic molecules. Toluene dispersed in the aqueous phase is used as a model compound, and it is efficiently adsorbed by the mineralized latex particles.