Rapid and accurate measurements of immune protein markers are essential for diagnosis and treatment in all clinical settings. The recent pandemic has revealed a stark need for developing new tools and assays that could be rapidly used in diverse settings and provide useful information to clinicians. Here, we describe the development and test application of a novel one-step CRP/IP-10 duplex assay for the LightDeck platform capable of delivering reproducible and accurate measurements in under eight minutes. We used the optimized assay to measure CRP and IP-10 levels in human blood and serum samples from healthy, COVID-19-positive, and influenza-like illness (ILI) presenting patients. Our results agreed with previously published analyte levels and enabled us to make statistically significant comparisons relevant to multiple clinical parameters. Our duplex assay is a simple and powerful tool for aiding diagnostic decisions in diverse settings.

The authors declare the following competing financial interests: LightDeck Diagnostics, Inc. is a commercial organization. J.Y., L.W., M.J.L, and C.M. are/were employees of LightDeck Diagnostics.

This project was supported by the Joint Project Lead for CBRND Enabling Biotechnologies (JPL CBRND EB) through contact W911QY-20-9-0004 (2020 OTA), and the Office of the Assistant Secretary of Defense for Health Affairs.

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Advarra IRB gave ethical approval for this work.

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All data produced in the present study are available upon reasonable request to the authors.