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bioRxiv · 10.1101/483347

Time-resolved digital immunoassay for rapid and sensitive quantitation of procalcitonin with plasmonic imaging

Jing, W.·Wang, Y.·Yang, Y.·Ma, G.·Wang, S.·Tao, N.
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Abstract

Timely diagnosis of acute diseases improves treatment outcomes and saves lives, but it requires fast and precision quantification of biomarkers. Here we report a time-resolved digital immunoassay based on plasmonic imaging of binding of single nanoparticles to biomarkers captured on a sensor surface. The real-time and high contrast of plasmonic imaging lead to fast and precise counting of the individual biomarkers over a wide dynamic range. We demonstrated the detection principle, evaluated the performance of the method using procalcitonin (PCT) as an example, and achieved a limit of detection of ~ 3 pg/mL, dynamic range of 4-12500 pg/mL, for a total detection time of ~ 25 mins.

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Jing, W., Wang, Y., Yang, Y., Ma, G., Wang, S., Tao, N.. 2018-11-29. Time-resolved digital immunoassay for rapid and sensitive quantitation of procalcitonin with plasmonic imaging. https://doi.org/10.1101/483347

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