Synthesis of Size-Controlled Monodisperse Manganese Carbonate Microparticles as Templates for Uniform Polyelectrolyte Microcapsule Formation

Inorganic colloids are usually prepared via precipitation reactions, which involve two sequential steps: nucleation and growth of the nuclei. On the basis of this theory, preformed manganese carbonate nanoseeds were prepared by mixing diluted ammonium hydrogen carbonate with manganese sulfate solution to serve as nuclei for production of monodisperse manganese carbonate microparticles. It was found that the average particle diameter can be finely tuned from 1 to 10 μm by adding a different volume of nanoseed solution. It was further verified that the manganese carbonate microparticles can be used as templates for efficient formation of uniform, smooth multilayer polyelectrolyte microcapsules, which are promising systems for biomedical and other applications, such as biosensors, bioreactors, and drug-delivery devices.