Effect of viscoelastic film for shear horizontal surface acoustic wave on quartz

Abstract

A numerical analysis for the mass loading sensitivity of shear horizontal surface acoustic wave (SH-SAW) immunoassay biosensors on quartz has already been studied. However, the mass loading analysis is insufficient to explain the actual biosensor performance. To understand the SH-SAW biosensor performance, we analyze the effect of a viscoelastic film on SH-SAW biosensors. In this paper, a numerical analysis using a simple viscoelastic model for the SH-SAW biosensors is presented. In the theoretical model, the bioreaction layer on the SH-SAW biosensors can be treated as a viscoelastic film. The velocity changes of the 250 MHz SH-SAWs on quartz substrates, which are covered with bovine serum albumin (BSA) layers of different thicknesses, were measured and compared with the theoretical results obtained using the proposed viscoelastic model. Good agreement of the velocity changes of SH-SAWs versus changes in the viscoelastic film thickness between theoretical and experimental results was obtained.

Shear-horizontal surface acoustic wave characteristics of a (110) ZnO/SiO2/Si multilayer structure

“…So far, SH-SAW devices using quartz [11], LiNbO 3 [10] and LiTaO 3 [12] have been employed as SAW sensors for chemical and biological sensing application. However, SH-SAW sensors on quartz suffer from low electromechanical coupling coefficients K 2 , high penetration depth, and low dielectric permittivity with respect to liquid media.…”

Evaluation of Shear Horizontal Surface Acoustic Wave Biosensors Using “Layer Parameter” Obtained from Sensor Responses during Immunoreaction

“…The measurement characteristics of SH-SAW biosensors were determined by the height dimension of the molecules formed on the sensing surface, as suggested by the experimental results; they were also verified through numerical simulations. A modified simulation was used as a numerical simulation method by adding viscosity effects to the Campbell and Jones method [ 24 , 25 , 26 ]. The numerical simulation assumes a four-layer structure: SAW substrate (quartz), sensing electrode (gold thin film, thickness: 92 nm), biomolecule layer (capture antibody, CRP, secondary antibody, and gold nanoparticle complex), and buffer solution layer.…”

“…The numerical simulation assumes a four-layer structure: SAW substrate (quartz), sensing electrode (gold thin film, thickness: 92 nm), biomolecule layer (capture antibody, CRP, secondary antibody, and gold nanoparticle complex), and buffer solution layer. A schematic of the calculation model is presented in simulation was used as a numerical simulation method by adding viscosity effects to the Campbell and Jones method [24][25][26]. The numerical simulation assumes a four-layer structure: SAW substrate (quartz), sensing electrode (gold thin film, thickness: 92 nm), biomolecule layer (capture antibody, CRP, secondary antibody, and gold nanoparticle complex), and buffer solution layer.…”

Properties of engine oil measured using a surface acoustic wave sensor

“…The SH-SAW is also affected by the loaded mass on the surface and the viscoelastic properties of the liquid or loaded material. 14,30) The sensitivity of the SH-SAW sensor depends on the piezoelectric substrate used. For the viscosity and loaded mass, the SH-SAW sensor fabricated on ST-cut X90-quartz has a high sensitivity.…”