Since the softness of the sample is affected by a large variety of parameters, the QCM-D is useful for studying molecular interactions with surfaces as well as interactions between molecules. The QCM-D is commonly used in the fields of biomaterials, cell adhesion, drug discovery, materials science, and biophysics. Other typical applications are characterizing viscoelastic films, conformational changes of deposited macromolecules, build-up of polyelectrolyte multilayers, and degradation or corrosion of films and coatings.