Universal dipstick platform for rapid visual detection of nucleic acids via isothermal amplification

Overview

This solution offers a rapid, equipment-light molecular diagnostic platform that combines loop-mediated isothermal amplification (LAMP) with universal lateral flow dipsticks for visual readout. The platform can detect and discriminate DNA and RNA targets, including single nucleotide polymorphisms (SNPs), within 25 minutes of amplification plus 5 minutes of dipstick development, and requires only minimal sample processing with no prior nucleic acid purification. Because amplification occurs at a constant 65°C rather than through thermal cycling, the system is suited to point-of-care and field settings where laboratory infrastructure is unavailable. A single universal dipstick design can be reused across many different targets, dramatically reducing development cost and time when adding new assays. Results can be captured photographically using a mobile device, enabling high-throughput testing across plate formats and straightforward record-keeping.

Technical specifications

The platform is built on two integrated components: a LAMP ready-mix and a universal analyte-independent dipstick (AID). The ready-mix uses an engineered polymerase tolerant to common inhibitors, allowing direct amplification from crude samples such as animal swabs or plant tissue. Dual-labelled primers (for example, biotin and fluorescein) produce amplicons that are captured on the dipstick at a test line via anti-fluorescein antibodies and visualised using neutravidin-conjugated nanoparticles. A built-in control line confirms dipstick functionality, and an additional amplification control line (for instance, targeting a housekeeping gene such as COX1) can be incorporated to verify that LAMP amplification itself was successful. Uracil-DNA glycosylase digestion of uracil-containing amplicons is included to prevent carry-over contamination. The same dipstick format supports multiplexed testing within standard 96-well plates, and new targets require only the design of standard labelled DNA oligos rather than bespoke strip development.

Technology readiness level

The core LAMP-AID technology is currently at Technology Readiness Level 3, having been validated in a BBSRC UK Food Safety Research Network project with Fera Science for the detection of Campylobacter contamination from unprocessed chicken carcass swabs. The team plans to adapt the platform to genetic quality assessment of leaf and seed material and reach TRL 6 (demonstration in point-of-use conditions) within 12 months through funded optimisation, additional control line development, and field demonstration. Fera Science contributes extensive experience in plant pathogen LAMP assays and crude DNA extraction from plant matrices, supporting the planned advancement toward point-of-use deployment.