Elliptical Electrode Design in QCM: Impact on Liquid Droplet Detection and Biosensing Efficiency

The demand for highly sensitive sensors is rising in biomedical applications. Quartz crystal microbalance (QCM) offers real-time monitoring but suffers from poor sensitivity and high sample consumption. This study introduces an elliptical electrode design and a single droplet-based assay to enhance QCM bio-detection. Using MIPDA-coated QCM crystals for pepsin detection, the elliptical design showed up to 10 times higher sensitivity than the standard 1-inch circular QCM. It also maintained linear sensitivity at 250 Hz/μl over a broader range. These findings lay the groundwork for next-generation QCM platforms with improved sensitivity for biomedical diagnostics and environmental monitoring