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bioRxiv · 10.1101/2024.07.05.602214

DNA Origami Signal Amplification in LateralFlow Immunoassays

Ijäs, H.·Trommler, J.·Nguyen, L.·van Rest, S.·Nickels, P. C.·Liedl, T.·Urban, M. J.
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Abstract

Lateral flow immunoassays (LFIAs) enable a rapid detection of analytes in a simple, paper-based test format. Despite their multiple advantages, such as low cost and ease of use, their low sensitivity compared to laboratory-based testing limits their use in e.g. many critical point-of-care applications. Here, we present a DNA origami-based signal amplification technology for LFIAs. DNA origami is used as a structurally precise adapter to connect detection antibodies to tailored numbers of signal-generating labels. As a proof of concept, we apply the DNA origami signal amplification in a sandwich-based LFIA for the detection of cardiac troponin I (cTnI) in human serum. We show a 55-fold improvement of the assay sensitivity with 40 nm gold nanoparticle labels and an adjustable signal amplification of up to 125-fold with fluorescent dyes. The technology is compatible with a wide range of existing analytes, labels, and sample matrices, and presents a modular approach for improving the sensitivity and reliability of lateral flow testing.

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Ijäs, H., Trommler, J., Nguyen, L., van Rest, S., Nickels, P. C., Liedl, T., Urban, M. J.. 2024-07-09. DNA Origami Signal Amplification in LateralFlow Immunoassays. https://doi.org/10.1101/2024.07.05.602214

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