Circuit Design and System Integration of Glucose Biosensor Based on Piezoelectric Effect

Abstract

Piezoelectric biosensors have become a new frontier in non-invasive and real-time glucose monitoring, providing an alternative to finger-pricking procedures that are unsatisfactory due to their inconvenience, pain, and costs. This paper presents multiple facets of the working principles, mechanisms of signal transduction, and approaches to system integration. The fundamental operational principles of piezoelectric materials are explained through the constitutive equations that describe the interconversion between mechanical stress and electric displacement. The transduction mechanisms translating surface interactions into electrical signals is facilitated by the Sauerbrey and Kanazawa-Gordon relations, linking mass loading and fluid properties to frequency shifts in quartz crystal microbalances (QCMs). Subsequent works involving surface acoustic wave (SAW) sensors and the use of polyvinylidene fluoride (PVDF) demonstrate the vastness of modes of piezoelectric signal conversion. The paper also addresses the electronic design and whether it improves the stability and amplification defines weak piezoelectric output through the Butterworth-Van Dyke equivalent circuit and charge amplifier. Collective improvements in surface chemistry, selective recognition, and circuit design can enhance sensitive, stable, and portable piezoelectric glucose biosensors. Cumulatively these advances represent the trajectory of practical, wearable, clinical glucose monitoring devices.