Giant Magnetoresistive Biosensing Platform for Point-of-Care Gene Expression Analysis

Influenza viruses are among the most common causes of respiratory viral infections globally. Detection and quantification of the host transcriptional response to influenza viruses can serve as a tool for timely diagnosis, triaging, and clinical management. However, use of gene expression analysis for clinical applications has traditionally been limited due to elaborate instrumentation requirements and slow turnaround-times. Using polymerase chain reaction (PCR) and giant magnetoresistive (GMR) biosensors, we present a highly automated and multiplexed point-of-care (POC) platform that quantifies the expression of 4 genes related to influenza infection within ~35 min. Further, we demonstrate that this platform may serve as a useful clinical tool for POC influenza diagnostics by showing that, in a study of 21 subjects, those infected with influenza viruses had higher overall expression when compared with influenza-negative subjects (p < 0.0001, n=21).