A Caltech Library Service

Hybridization Chain Reaction Lateral Flow Assays for Amplified Instrument-Free At-Home SARS-CoV-2 Testing

Schulte, Samuel J. and Huang, Jining and Pierce, Niles A. (2023) Hybridization Chain Reaction Lateral Flow Assays for Amplified Instrument-Free At-Home SARS-CoV-2 Testing. ACS Infectious Diseases, 9 (3). pp. 450-458. ISSN 2373-8227. PMCID PMC9924079. doi:10.1021/acsinfecdis.2c00472.

[img] PDF - Published Version
Creative Commons Attribution.

[img] PDF (Materials, additional methods, replicate data, and additional studies) - Supplemental Material
Creative Commons Attribution.

[img] Video (MPEG) (Supplementary Movie 1) - Supplemental Material
Creative Commons Attribution.

[img] Video (MPEG) (Supplementary Movie 2) - Supplemental Material
Creative Commons Attribution.


Use this Persistent URL to link to this item:


The lateral flow assay format enables rapid, instrument-free, at-home testing for SARS-CoV-2. Due to the absence of signal amplification, this simplicity comes at a cost in sensitivity. Here, we enhance sensitivity by developing an amplified lateral flow assay that incorporates isothermal, enzyme-free signal amplification based on the mechanism of hybridization chain reaction (HCR). The simplicity of the user experience is maintained using a disposable 3-channel lateral flow device to automatically deliver reagents to the test region in three successive stages without user interaction. To perform a test, the user loads the sample, closes the device, and reads the result by eye after 60 min. Detecting gamma-irradiated SARS-CoV-2 virions in a mixture of saliva and extraction buffer, the current amplified HCR lateral flow assay achieves a limit of detection of 200 copies/μL using available antibodies to target the SARS-CoV-2 nucleocapsid protein. By comparison, five commercial unamplified lateral flow assays that use proprietary antibodies exhibit limits of detection of 500 copies/μL, 1000 copies/μL, 2000 copies/μL, 2000 copies/μL, and 20,000 copies/μL. By swapping out antibody probes to target different pathogens, amplified HCR lateral flow assays offer a platform for simple, rapid, and sensitive at-home testing for infectious diseases. As an alternative to viral protein detection, we further introduce an HCR lateral flow assay for viral RNA detection.

Item Type:Article
Related URLs:
URLURL TypeDescription CentralArticle InCaltech News ItemDiscussion Paper
Schulte, Samuel J.0000-0001-9982-6504
Huang, Jining0000-0002-3798-4790
Pierce, Niles A.0000-0003-2367-4406
Additional Information:© 2023 The Authors. Published by American Chemical Society. Permits the broadest form of re-use including for commercial purposes, provided that author attribution and integrity are maintained ( We thank M. Schwarzkopf and K. S. Lee for performing preliminary studies. We thank M. E. Bronner for reading a draft of the manuscript. We thank M. Schwarzkopf, K. S. Lee, L. M. Hochrein, G. Shin, B. J. Wold, and R. F. Ismagilov for helpful discussions. We thank G. Shin of the Molecular Technologies resource within the Beckman Institute at Caltech for providing HCR reagents. This work was funded by the Shurl and Kay Curci Foundation, by the Richard N. Merkin Institute for Translational Research at Caltech, by the National Aeronautics and Space Administration (Translational Research Institute for Space Health; NNX16AO69A), and by the National Institutes of Health (NIBIB R01EB006192 and NIGMS training grant GM008042 to S.J.S.). Author Contributions. S.J.S. and J.H. contributed equally. The authors declare the following competing financial interest(s): Patents, pending patent applications, and the startup company Molecular Instruments.
Group:COVID-19, Richard N. Merkin Institute for Translational Research
Funding AgencyGrant Number
Shurl and Kay Curci FoundationUNSPECIFIED
Caltech Merkin Institute for Translational ResearchUNSPECIFIED
NIH Predoctoral FellowshipGM008042
Issue or Number:3
PubMed Central ID:PMC9924079
Record Number:CaltechAUTHORS:20230227-258668000.1
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:119516
Deposited By: George Porter
Deposited On:28 Feb 2023 03:12
Last Modified:15 May 2023 17:27

Repository Staff Only: item control page