3. Conclusions

The quartz crystal microbalance is a highly sensitive measuring instrument based on the piezoelectric properties of quartz. It has been used since the 1960s to monitor thickness variations during vacuum deposition. The method's scope of application has broadened considerably since the 1980s-1990s, when its use in liquid media was the focus of numerous developments. QCM can be used as a probe to study solutions, deposits and interfaces. In its electrochemical variant, the potential of one of the electrodes can be controlled, enabling adjustment of the surface charge and/or redox state of the species present. The sensitivity of CQM enables the study of monolayer fractions. Recently, the method has undergone further development with the creation of sensors, notably by combining the resonator with highly specific biological molecules. Immunosensors have thus been developed. A new technological...