4D-3 Multi-Layer Interfacial Property Analysis Using a Multi-Frequency Thickness Shear Mode (MFTSM) Device Built on a Single-Chip

Biological interfaces between synthetic materials and biological systems such as tissue engineering, biomaterials, and biosensors constitute one of the most dynamic and expanding fields in science and technology. There is then a need for rapid, quantitative, sensitive and accurate monitoring of important multi-layered biological interfacial processes. In this project, a novel biochip, consisting of arrays of single and multi-frequency thickness shear mode (MFTSM) sensors was fabricated and tested. This simple, fast, low cost biochip device can accurately monitor multi-layer interfacial properties with high temporal and spatial resolution and measure different interfacial processes simultaneously under a broad range of experimental conditions. Results obtained from the MFTSM biochip were compared to those obtained from single TSM using fundamental and harmonic frequencies. The biochip was designed to have six membrane thicknesses, namely 15 MHz, 20 MHz, 25 MHz, 41 MHz, 60 MHz and 70 MHz were etched on the same piezoelectric quartz substrate. For comparison, a single 5 MHz TSM was used as the reference system.