Automated liquid handling robot for rapid lateral flow assay development

Abstract

The lateral flow assay (LFA) is one of the most popular technologies on the point-of-care diagnostics market due to its low cost and ease of use, with applications ranging from pregnancy to environmental toxins to infectious disease. While the use of these tests is relatively straightforward, significant development time and effort are required to create tests that are both sensitive and specific. Workflows to guide the LFA development process exist but moving from target selection to an LFA that is ready for field testing can be labor intensive, resource heavy, and time consuming. To reduce the cost and the duration of the LFA development process, we introduce a novel development platform centered on the flexibility, speed, and throughput of an automated robotic liquid handling system. The system comprises LFA-specific hardware and software that enable large optimization experiments with discrete and continuous variables such as antibody pair selection or reagent concentration. Initial validation of the platform was demonstrated during development of a malaria LFA but was readily expanded to encompass development of SARS-CoV-2 and Mycobacterium tuberculosis LFAs. The validity of the platform, where optimization experiments are run directly on LFAs rather than in solution, was based on a direct comparison between the robotic system and a more traditional ELISA-like method. By minimizing hands-on time, maximizing experiment size, and enabling improved reproducibility, the robotic system improved the quality and quantity of LFA assay development efforts. Graphical abstract

Performance of novel antibodies for lipoarabinomannan to develop diagnostic tests for Mycobacterium tuberculosis

“…In a rapid antigen test, the exposure time of the antibody to its target is likely a few seconds at most and so the kinetics of what binds best are different from a liquid immunoassay. A recent study compared a subset of Ig pairs in this work (289 pairs) via detection of Aoyoma-B cLAM on the MSD platform versus an LFA screening platform [30]. In comparing signal outputs from both methods, they showed a weak positive correlation, with R values of 0.30 (p < 0.0001) and 0.36 (p < 0.0001) for S-N and S/N.…”

“…Recent advances to increase the sensitivity of LAM immunoassays have focused on developing Igs with improved sensitivity and specificity to TB LAM [22][23][24][25][26], sample preparation including pre-treatment to remove confounders [27][28][29], pre-enrichment of uLAM from urine prior to testing [30,31], amplifying the stripe signal [32] or highly sensitive immunoassay platforms [33][34][35]. Our aim was to assess the analytical performance of TB LAM antibodies (Igs) to identify pairs that offer superior performance over existing urine LAM tests.…”

Accelerated Development of a COVID-19 Lateral Flow Test in an Academic Setting: Lessons Learned

“…This format is frequently used for the initial LFA development. Others have developed a robotic-assisted platform for the efficient antibody screening on LFA strips. , The nucleoprotein is a highly conserved and abundantly expressed structural protein and the target of most FDA-cleared antigen tests. Antibodies were conjugated to commercial 200 nm blue fluorescent carboxylated particles (excitation 365 nm/emission 415 nm, ThermoFisher Fluorospheres F8805) using EDC/NHS conjugation chemistry after we tested a variety of particles and confirmed their compatibility with Glow chemi-excitation.…”

Paper based microfluidic devices: a review of fabrication techniques and applications

“…All three reagents in the porous substance attached at the same time and were closest to the detection zone overall arrived and reached the detection zone first. In an effort to cut the price and size of the LFAs development process, Anderson et al [ 54 ] offered a revolutionary platform centered on the adaptability and capacity of an autonomous fluid handling system. The technology was first successfully used to create an LFA for malaria, but it was quickly expanded to allow for the development of LFAs for SARS-CoV-2 and Mycobacterium tuberculosis as well.…”