Topical Problems of Fluid Mechanics


Institute of Thermomechanics AS CR, v.v.i.	CTU in Prague Faculty of Mech. Engineering Dept. Tech. Mathematics	MIO Université du Sud Toulon Var - AMU - CNRS - IRD	Czech Pilot centre ERCOFTAC

Improving QCM Biosensor Efficiency by Flow Cell Modification
Kubíčková L., Studeník O., Plachá M., Isoz M.
Abstract:
Biosensors based on quartz crystal microbalance (QCM) are often used for detection of biomolecules, pathogens, or viruses. The biological analyte gets captured at the QCM crystal surface, leading to a change in the crystal resonant frequency and analyte detection. However, with standard biosensor geometry, most of the analyte is captured in regions where the crystal sensitivity is limited. In this work, we investigate how changes in the biosensor geometry influence the spatial distribution of the captured analyte. Using a custom implementation of an immersed boundary method, we add obstacles on the non-detecting top wall of the biosensor flow cell, which is motivated by the possibility to 3D print this surface. Next, we simulate the biomolecules as Lagrangian particles with the Brownian motion taken into account and evaluate the probability of the analyte detection. Several different variants of obstacle shapes and layouts were tested. With the best obstacle configuration found, the amount of analyte captured in the most sensitive region of the crystal was 17% higher than in the standard configuration. The obtained results may be used (i) to generate QCM sensor geometries and validate this computational study, and (ii) as a basis for the development of less computationally demanding models usable in automatic optimization of the QCM biosensor geometry.
Keywords:
CFD, lagrangian particle tracking, OpenFOAM, biosensor

Fulltext: PDF DOI: https://doi.org/10.14311/TPFM.2025.021

In Proceedings Topical Problems of Fluid Mechanics 2025, Prague, 2025, Edited by David Šimurda and Tomáš Bodnár, pp. 159 ISBN 978-80-87012-05-5 (Print) ISSN 2336-5781 (Print)