Characterization of a Quartz Crystal Microbalance with Dissipation Monitoring Prototype Utilizing Human Tears

The Quartz Crystal Microbalance with Monitoring Dissipation (QCM-D) is a piezoelectric sensor with high sensitivity to small variations in the substance deposited on it. The advantage over other measurement instruments is that it requires a low sample volume to function, making it applicable to characterize low-volume biological substances as tears. Tears alterations can be a source of information to evaluate a considerable number of diseases, with the benefit that their extraction is not invasive. Previously, the authors of this work carried out a robust and low-cost experimental biomedical prototype manufactured for the identification of properties of low volume biological substances. This work presents the characterization of the mentioned prototype with human tears by measuring the resonance and dissipation frequency of the QCM-D. The statistics show an acceptable repeatability in the measurement of both parameters.