Differential Impedance Biosensing platform for early diagnosis of viral infections

Detection of viruses is essential for the control and prevention of viral infections. In recent years, there has been a focus on simpler and faster detection methods, particularly through the use of electronic-based detection in a point-of-care configuration. The proposed biosensor platform can provide high-resolution measurements of viral infections by detecting antibodies. The system is based on differential impedance measurement of the biological target with nanoparticle amplification. The surface of the sensor is biochemically functionalized with a synthetic peptide to mimic the antigenic determinant of the targeted virion particle. Gold interdigitated microelectrodes are the core of the biosensing system. They are designed in a differential configuration, reference and active sensor, to counteract all possible mismatches such as temperature fluctuations and variations in the ion content of the solution. The successful combination of these elements makes it possible to reach a limit of detection of the system below 100 pg/mL for IgG antibodies in buffer. Furthermore, the biosensing system has been challenged with infected human serum samples for digital counts of antidengue virus antibodies, achieving the detection of clinically relevant target concentrations.