Abstract: A new bio-mimetic bulk acoustic wave (BAW) sensor for paracetamol, with a high selectivity and sensitivity, was fabricated by using the molecularly imprinted polymer (MIP) as the sensing material. Non-covalent molecular imprinting polymers were synthesized simultaneously using two different functional monomers, namely the weakly basic 4-vinylpyridine (4-VP) and the acidic and hydrogen binding methacrylic acid (MAA). Such imprinted polymers improved recognition capability as compared with the polymers that were synthesized using only one of the functional monomers. Dynamic quartz crystal impedance analysis was employed to study the effect of the viscoelasticity of the polymer coating on the measurement. There was no variation in the viscoelasticity during the detection. The sensor was stable and exhibited good reproducibility. Satisfactory results were obtained in the determination of paracetamol in real samples. (C) 2001 Elsevier Science B.V. All rights reserved