The building of molecularly imprinted single hole hollow particles: A miniemulsion polymerization approach

The structural design on the molecularly imprinted polymers (MIP) has been increasingly concerned because of advanced recognition efficiency. We here demonstrate a facile miniemulsion based polymerization to synthesize single hole hollow MIP particles for the recognition of bisphenol A (BPA). Uniform submicron products can be achieved through one-step polymerization in the aqueous dispersion, where the polymer seed has been swelled in the miniemulsion of the cross-linker and functional monomers together with the template molecules of BPA. After the removal of the seed and the template molecules by extraction, the electron microscopy characterization reveals bowl-like particles with a single hole on the concave surface. The unique single hole hollow structure is determined by the polymerization induced phase separation in the miniemulsion droplets and can be altered by monomer components. The characteristic of MIP is illustrated by the molecular recognition in the rebinding tests, where the particles prepared under the optimal formulation exhibit remarkable kinetics and desirable selectivity towards BPA in the mixed solution of methanol and water (20:80, v/v). The MIP particles with single hole hollow structure would be attractive in environmental and analytic fields for BPA decontamination.