3,4-Methylenedioxymethylamphetamine detection using a microcantilever-based biosensor

We developed a biomolecular layer with highly specific binding that enables determination of low concentrations of 3,4-methylenedioxymethylamphetamine (MDMA) by the immobilization of antibodies. This study examined the interactions of anti-MDMA antibodies with MDMA using a microcantilever-based biosensor. The detection platform is based on the immobilization of affinity monoclonal antibodies onto a sensing surface using a cysteamine-based self-assembled monolayer. Anti-MDMA antibodies conjugated with various concentrations of MDMA were bound to the sensing surface. The intermolecular interaction was observed by monitoring the simultaneous signals (bending deflection and resonant frequency shift) of microcantilevers in phosphate buffered saline (PBS). We demonstrated that anti-MDMA antibodies can respond specifically to their natural ligand, MDMA. Results revealed that the microcantilever-based biosensor can be used to characterize MDMA response profiles of anti-MDMA and provide rich data for immunoassays. In addition to providing a clearer understanding of the biological mechanisms of protein binding, such a biosensor also holds great potential in numerous other fields, such as drug detection, biomedicine, and environmental protection. (C) 2012 Elsevier B.V. All rights reserved.