Fig. 4

The basic principle of biosensors. The commonly used detection samples for biosensors mainly include cells, tissues, and body fluids. The target substances in the samples bind with the biorecognition elements of the sensor, such as enzymes, antibodies, and nucleic acids, to produce physical or chemical reactions. Then, the sensor’s transducer converts these reactions into measurable signals, such as electrical or optical signals. Finally, after data processing, the detection of the target substances is achieved