A novel, molecularly imprinted, upconversion fluorescence probe (UCNP@MIFP) for sulfonamide sensing was fabricated by Pickering emulsion polymerization using UCNP@SiO2 particles as the stabilizer and sulfamethazine/sulfamerazine as the co-templates. The synthesis conditions of the UCNP@MIFP were optimized, and the synthesized probe was characterized by scanning electron microscopy, Fourier transform infrared spectrometer, thermogravimetric analyzer, and fluorescence spectrometer. The UCNP@MIFPs showed a good adsorption capacity and a fast kinetic feature for the template. The selectivity experiment revealed that the UCNP@MIFP has a broad-spectrum molecular recognition capability. Good linear relationships were obtained over the concentration range of 1-10 ng/mL for sulfamerazine, sulfamethazine, sulfathiazole, and sulfafurazole, with low limits of detection in the range of 1.37-2.35 ng/mL. The prepared UCNP@MIFP has the potential to detect four sulfonamide residues in food and environmental water.
Keywords: Pickering emulsion polymerization; molecularly imprinted polymer; sulfonamides; upconversion fluorescence probe.