Paper-Based Cascade Isotachophoretic Technology: Rapid Multiplex Assay to Differentiate Bacterial and Viral Infections

Washington State University, Pullman WA

Investigators

Abstract

There are about 250 million episodes of acute infectious disease annually in the U.S., leading to 40 million patients being admitted to emergency rooms. A major challenge to treating infected patients effectively is the clinical difficulty in distinguishing between diseases caused by bacterial infection and those caused by viral infection, because they often present with similar clinical symptoms. This uncertainty directly leads to antibiotic misuse which, in turn, contributes to the development of antibiotic resistant microbes. Therefore, it is important to help physicians make evidence-based antibiotic treatment decisions during the time of a patient visit by providing rapid, accurate diagnostic tools that can distinguish between the bacterial and viral infections. Currently, there is no such technology that can meet the need. This research project aims to develop a novel technology that can quickly and accurately detect biomarkers useful for distinguishing between bacterial and viral infections. The method involves a paper-based device for separating and concentrating protein components and a mobile phone-based detection unit. The outcomes of this research could lead to a cost-effective diagnostic tool that will help to improve patient outcomes, lower healthcare costs, and reduce the over administration of broad-spectrum antibiotics and, therefore, antibiotic resistance. The research project serves as a training ground for graduate and undergraduate students to perform cutting edge research. The results of this research will be disseminated widely by making the technology accessible to other institutions across the nation, publishing outcomes in peer-reviewed journals, and presenting results to the science and engineering community at national meetings and conferences. Routine diagnostic tests in central laboratories for pathogen detection can assist physicians in the etiological determination of an underlying infectious process. However, such tests can take days to return results, can be expensive, and usually require special instruments and well-trained personnel. Recently, a host-based diagnostic protein panel, including both the bacteria-induced proteins procalcitonin and C-reactive protein (CRP) and the virus-induced tumor necrosis factor related apoptosis-inducing ligand (TRAIL) and interferon-induced protein-10 (IP-10), has been established to discriminate between bacterial and viral infection with remarkable sensitivity and specificity. However, detecting this protein panel is difficult and slow because of the ultra-low concentrations of the proteins in circulation and the interference caused by abundant plasma proteins. Therefore, the panel test must be run by a diagnostic laboratory and not at the point-of-care. This research project aims to develop an integrated paper-based cascade isotachophoresis (ITP) platform on which the panel proteins in blood will be 1) separated from the abundant plasma contaminant proteins by cationic ITP in the presence of specific target immune-bindings, 2) continuously enriched through cascade ITP focusing, 3) immune-captured at an elevated concentration by a unique single test line with graded target binding, and 4) multiplex-detected with a miniaturized smartphone-based point-of-care optosensing module. By combining the unique on-board purification and enrichment power of ITP stacking, paper-based lateral flow, and smartphone-based detection, this approach can create an integrated, point-of-care technology capable of the multiplex detection of circulating disease markers that are present either at an ultralow level or within a broad dynamic concentration range. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.