A High Fundamental Frequency Quartz Crystal Biosensor Integrated into an Electro-wetting-on-dielectrics Based Lab-on-a-chip

We demonstrate the operation of an Electro Wetting on Dielectrics (EWOD) hybrid lab-on-a-chip system by utilizing a Quartz Crystal Microbalance (QCM) resonator as mass-sensitive sensor. We have tested the formation of a phosphorlipid monolayer out of an aqueous buffer suspension onto the integrated sensor. The altered mass load resulted in a shift of the resonance frequencies. Subsequently, the formation of a protein multilayer was monitored by QCM frequency and contact angle measurements. Using these sample applications, we were able to demonstrate and verify the feasibility of our prototype combining a mass-sensitive QCM sensor with digital microfluidics based on EWOD.