Biomimetic bulk acoustic wave sensor for determination of trimethoprim in the organic phase based on a molecular imprinting polymer

A molecular imprinted polymer was prepared using trimethoprim as the template molecule and methacrylic acid as the functional monomer by a non-covalent method. The powders of the polymer were coated on one electrode of a bulk acoustic wave (BAW) device to construct a biomimetic sensor for the determination of trimethoprim. In absolute ethanol, the sensor exhibited good selectivity and sensitivity. In the range of 6.0x10(-8) - 6.7x10(-5) M, there was a linear relationship between log(-Delta f) and log C. The detection limit was 4.0x10(-8) M. When treated by heat, heavy metal salt, acid, etc., the sensor still exhibited long-time stability and resistance to such harsh chemical environments. Satisfactory results of a real sample assay were obtained by the proposed method.