Simultaneous electrical detection of IL-6 and PCT using a microfluidic biochip platform

Sepsis, a life-threatening organ dysfunction caused by a dysregulated host response, leads the U.S in both mortality rate and cost of treatment. Sepsis treatment protocols currently rely on broad and non-specific parameters like heart and respiration rate, and temperature; however, studies show that biomarkers Interlukin-6 (IL-6) and Procalcitonin (PCT) correlate to sepsis progression and response to treatment. Prior work also suggests that using multi-parameter predictive analytics with biomarkers and clinical information can inform treatment to improve outcome. A point-of-care (POC) platform that provides information for multiple biomarkers can aid in the diagnosis and prognosis of potentially septic patients. Using impedance cytometry, microbead immunoassays, and biotin-streptavidin binding, we report a microfluidic POC system that correlates microbead capture to IL-6 and PCT concentrations. A multiplexed microbead immunoassay is developed and validated for simultaneous detection of both IL-6 and PCT from human plasma samples. Using the POC platform, we quantified plasma samples containing healthy, medium (~10³pg/ml) and high (~10⁵pg/ml) IL-6 and PCT concentrations with various levels of significance (P < 0.05-P < 0.00001) and validated the concept of this device as a POC platform for sepsis biomarkers.