Abstract: A new thickness-shear mode (TSM) acoustic sensor for the determination of atrazine was fabricated using a molecularly imprinted polymer (MIP) as recognition element. The influence of functional monomers on sensor response was investigated. The experiment conditions such as pH and the amount of coating were optimized. The sensor showed high sensitivity and selectivity to the template atrazine. At the range of concentrations detected, the relationship between the frequency shift (- Deltaf) and log(C) was obtained with a polynomial fitting programme. The determination limit was 2.0 x 10(-6) mol/l. This method seems to be applicable for the development of mass sensor, combining the advantages of both biological receptors and synthetic imprinted polymers. (C) 2001 Elsevier Science B.V. All rights reserved