Sprecher
Beschreibung
Lateral flow assays (LFAs) are paper-based rapid test devices with a wide range of applications enabled by their high speed, affordability, and ease of use. Most conventional LFAs operate on a sandwich immunoassay format, using antibodies to capture target analytes. A visual signal that indicates a positive test result is generated by nanoparticles, typically colloidal gold, conjugated to detection antibodies. In point-of-care diagnostics, LFAs are employed for e.g. detecting infectious diseases and monitoring health conditions, but they still lack the sensitivity required for many critical applications.
We demonstrate that DNA origami nanostructures can be integrated into standard LFA formats to tackle this sensitivity limitation. DNA origami enables the spatial organization of external molecules – such as proteins, fluorophores, and nanoparticles – on a single nanostructure with Ångström-level precision. We employ DNA origami nanostructures as molecular adaptors between the detection antibodies and labels in LFAs and demonstrate drastically improved detection sensitivity for a broad range of analytes. In particular, we highlight enhanced performance in detecting cardiac troponin I – a key biomarker for heart attacks – and viral proteins relevant to respiratory infections. Using spiked buffer and serum samples, we detect sub-picomolar concentrations of analytes. Further, we show superior performance compared to commercial LFAs in clinical settings.
With the demonstrated sensitivity enhancement and with material costs increased by less than one cent per test, DNA origami represents a practical and scalable strategy for upgrading existing LFAs, and a crucial step toward the integration of DNA nanotechnology into commercial diagnostic devices.
