In this context, biosensors seem to be promising tools. In this case, the scheme for the detection of the pesticides is associated with their ability to inhibit one enzyme such as the acetyl- or butyrylcholinesterase AcChE or BuChE . Ž . Normally, AcChE and BuChE hydrolyze acetylcholine chloride and butyrylcholine chloride, while acid and choline species are formed.