A CMOS radio frequency biosensor for rapid detection and screening of sputum-mucin viscosity

This paper presents a CMOS radio frequency dielectric sensor platform for the detection of relative viscosity changes in sputum-mucin. The operating frequency of the sensor is 12 GHz. The sensor chip has been fabricated in 250 nm SiGe:C BiCMOS technology of IHP. The work shows that the sensor can distinguish between a highly viscous clot of sputum-mucin and dilute sputum-mucin. The viscosity of sputum is often regarded as a distinguishing feature of lung diseases and therefore, the sensor's capability of rapid detection of sputum viscosity makes it suitable for fast screening of lung diseases. A change of 200 MHz in the resonant frequency is shown for a change of 60% in the sputum-mucin viscosity. The sensor shown in this work is first of its kind to be used for detecting viscosity changes in a biological sample and is proposed to be used for future medical diagnostic tool for rapid screening of infectious lung diseases.