The working principle of piezoelectric biosensors involves the conversion of a biological interaction into an electrical signal. Here's a simplified explanation:
1. Recognition Element: A biological recognition element, such as an antibody, enzyme, or nucleic acid, is immobilized on the surface of the piezoelectric crystal. 2. Target Binding: When a target molecule (e.g., a cancer biomarker) from a sample binds to the recognition element, it causes a mass change on the crystal surface. 3. Frequency Shift: This mass change alters the resonance frequency of the crystal. 4. Signal Transduction: The change in frequency is converted into an electrical signal, which can be measured and analyzed.
