Smartphone-read phage lateral flow assay for point-of-care detection of infection

Abstract

The COVID-19 pandemic has highlighted the urgent need for sensitive, affordable, and widely accessible testing at the point of care. Here we demonstrate a new, universal LFA platform technology using...

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

“…Unfortunately, most LFA formats of sufficient sensitivity are poorly suited for widespread home self-testing, including organic fluorophores, − europium chelates, , up-converting phosphors, − and quantum dots − that offer high analytical sensitivity but require a complex apparatus for excitation/detection , and/or are unstable, photobleachable, or require narrow excitation/emission wavelengths . Enzyme-based chemiluminescent LFAs can provide ultrasensitive analysis but require often-unstable reporter substrates.…”

“…The analyte concentration of 280 TCID50/mL was further tested in five replicates to confirm the LoD (Figure C). We adapted the Yale SalivaDirect PCR assay, which circumvents RNA extraction, and performed RT-PCR in house directly on nasal swab extracts to benchmark serially diluted pooled samples during LFA optimization and to check occasional fresh nasal specimens. There is no general consensus on the required analytical sensitivity to ensure clinical utility, but our Glow LFA was described by RADx as being (at that time) “the second most sensitive LFA” in the program, with the most sensitive being a commercial test based on the glow-in-the-dark nanophosphors previously developed in the Willson laboratory, with a reported LoD of 82 TCID50/mL. , …”

“…The COVID-19 pandemic emphasized the urgent need for user-centered, reliable, and cost-effective point-of-care diagnostics that can be broadly deployed, ideally for self-testing at home. The Willson laboratory at the University of Houston focuses on the development of sensitive, translatable analytical methods for point-of-care diagnostics, especially tests using novel reporter technologies readable by a smartphone, and had developed an early proof-of-principle of novel LFA technologies potentially applicable to this need. − …”

Electrochemical vs. Optical Biosensors for Point-of-Care Applications: A Critical Review

“…The implementation of CL detection with the smartphone camera has been also investigated. Chabi et al [123] reported an LFIA platform employing phage-based CL reporters, combined with smartphone detection and applied to the diagnosis of SARS-CoV-2. Exploiting the same approach, Ren et al [124], trying to increase the sensitivity of the system, proposed a CL-LFIA based on the synthesis of the Au NP-antibody-HRP-polyethylene glyco conjugate for detecting cardiac troponin I (Figure 3b).…”

Electrochemical vs Optical Biosensors for Point of Care Applications: A Critical Review

“…The implementation of CL detection with smartphone camera has been also investigated. Chabi et al [116] reported a LFIA platform employing phage-based CL reporters, combined with smartphone detection and applied to the diagnosis of SARS-CoV-2. Exploiting the same approach Ren et al [117] trying to increase the sensitivity of the system, proposed a CL-LFIA based on the synthesis of the Au NP-antibody-HRP-polyethylene glycol conjugate for detecting cardiac troponin I (Figure 3b).…”