CRISPR-Cas based diagnostics use programmable Cas enzymes, most commonly Cas12 or Cas13, guided by a short RNA sequence that recognizes a specific DNA or RNA target. When the Cas enzyme’s guide RNA binds its intended target, the enzyme becomes activated and begins cleaving nearby single-stranded reporter molecules, a behavior known as collateral cleavage.

This mechanism gives CRISPR-based detection a level of specificity that goes beyond simple hybridization or tag capture, since the guide RNA can be designed to distinguish targets that differ by a single base, making the method useful for detecting point mutations and closely related pathogen strains.

CRISPR detection is typically paired with an isothermal amplification step, such as LAMP or RPA, to bring the target concentration up before the Cas enzyme is introduced, allowing the combined workflow to reach very high sensitivity.

In a CRISPR-Cas lateral flow assay, the reporter molecule is designed with a label on one end and a hapten, such as biotin, on the other. When the target is absent, the Cas enzyme remains inactive and the intact, dual-labeled reporter is captured at the strip’s test line, producing a visible band. When the target is present, the activated Cas enzyme cleaves the reporter before it reaches the test line, so no band forms there, while a control line elsewhere on the strip confirms the assay ran correctly.

Depending on the specific kit design, this relationship can also be reversed, so it is worth confirming with your protocol whether a test line appearing indicates a positive or negative result.

Because CRISPR-Cas assays rely on reporter cleavage rather than straightforward tag capture, Attogene offers kits specifically engineered to support this workflow:

AU2042, AU2045, and AU2056: purpose-built for CRISPR-Cas lateral flow applications, designed to reliably distinguish between cleaved and intact reporter molecules for a clear, easy-to-read result.

AU2034 (two-line format): this general-purpose NAAT kit can also support CRISPR-Cas detection, offering a simpler two-line readout for researchers who prefer a more streamlined format.

These kits are built to pair with upstream LAMP or RPA amplification, giving researchers a complete workflow from target amplification through CRISPR-based confirmation to a visual lateral flow readout.

All Attogene lateral flow strips for CRISPR-Cas detection are available in both dipstick and cassette formats. Specialized lateral flow running buffers and blood separation pads are also available upon request for applications working directly with whole blood samples.

CRISPR-Cas lateral flow assays are especially valuable where high specificity matters, including infectious disease diagnostics that must distinguish closely related pathogen strains, and genotyping applications such as detecting single point mutations linked to disease.

Looking to build a CRISPR-based assay around a specific target? Attogene’s custom lateral flow development services can help design a kit for your application. Learn more about our custom NAAT lateral flow services.