Moreover, miniaturisation of the instrumentation is possible, making this transduction method very attractive for the development of portable devices for in situ monitoring. Especially interesting are techniques that do not require labels for the transduction of the binding event, such as piezoelectrochemical detection or surface plasmon resonance (optical technique based on the change in the refractive index of a surface when a biomolecule is immobilised or when an affinity interaction
occurs).