Label-free GaN HEMT-based biosensing platform for interferon-γ detection

Intracranial injury such as traumatic brain injury is caused by sudden injury to the brain from external mechanical force causing health loss and disability worldwide. The work reports the design and development of a GaN HEMT-based biosensor and system for the detection of IFN-gamma for non-invasive detection of TBI. The developed platform can detect and differentiate IFN-gamma with a peak sensitivity of 109.08 mu A/pg/ml, high specificity, and good reproducibility. The platform offers good linearity with an LOD and LOQ of 6.82 fg/ml and 20.68 fg/ml respectively. The antibody-antigen binding has been confirmed with electrical and FTIR measurement techniques. A comparative analysis of system-level detection with on-chip measurement for validating the proposed readout interface shows a good match and thus confirms the system's suitability for the detection of IFN-gamma in clinically relevant concentration ranges. The system level and on-chip measurement show a similar sensitivity of 21.59 mu A/pg/ml and 19.05 mu A/pg/ml respectively. The proposed platform offers a highly stable biofunctionalization protocol with high specificity and selectivity. Thus, the platform has a good potential for point-of-care system development suitable for on-field and clinical applications.