The theory of acoustic sensors application in air quality control

Analysis of trypsin activity at β-casein layers formed on hydrophobic surfaces using a multiharmonic acoustic method

“…Voinova et al described mathematically the Voigt model for a crystal coated with a polymeric adlayer in a liquid medium. 27,28 In this approach, the correlation between the film and liquid viscoelastic properties and the Δf and ΔD responses are described by the equations:…”

Application of Multiharmonic QCM-D for Detection of Plasmin at Hydrophobic Surfaces Modified by β-Casein

“…Most recently we applied multiharmonic analysis of viscoelastic properties of β-casein layers following cleavage by trypsin [23]. This analysis has been based on a Voinova-Voigt model using following equations [21,22]:…”

“…It was demonstrated that the β-casein layer can be used for labelfree detection of the plasmin proteolysis. Furthermore, by means of the Voinova-Voigt viscoelastic model [22,30], it was possible to quantify the changes in viscoelastic values and describe the architecture of the β-casein layer.…”

“…This approach allowed not only the detection of plasmin activity, but also the analysis of the changes of viscoelastic properties of β-casein layers during the cleavage by plasmin. Moreover, using the Voinova-Voigt viscoelastic model [21,22], it was possible to quantify the variations of viscoelastic parameters during plasmin cleavage and to describe the architecture of the β-casein layer. The viscoelastic properties of β-casein layers following plasmin cleavage were compared with those caused by trypsin using the results of a recently published paper [23].…”