Lateral Flow enabling Low Cost Molecular Diagnostics at the Point of Care
Lateral flow assays (LFAs) are the mainstay of rapid point of care (POC) diagnostics, with the potential to enable early case management and transform the epidemiology of infectious disease. However, there are recognised limits in terms of sensitivity and specificity when compared to tests performed in a central laboratory.
Given the complex nature of human disease, overlapping symptoms and states of co-infections, there is increasing demand for multiplexed systems that can detect multiple biomarkers simultaneously and for improved sensitivity/specificity at the POC.
Polymerase chain reaction (PCR) is considered one of the gold standard diagnostic tests due to the high accuracy of the technology, which accounts for its use in central and reference laboratories.
It can detect disease with as few as several copies of a gene but due to complicated workflows, complex procedures, a requirement for cold chain storage, and time and economic costs, PCR hasn’t been truly feasible in a POC setting.
Several isothermal platforms have now entered the POC market for use in clinicians’ offices and clinics, however these tend to still require an expensive instrument and cold storage for reagents.
The challenge traditionally associated with PCR are improving the development of new amplification methods, microfluidics and the integration with lateral flow assay technology. A blend of these innovations is bringing new platforms to the market that provide end users with much simplified workflows, room temperature stable reagents, lower costs, and the ease of use associated with current lateral flow methods.
For end users of POC assays this will provide the convenience and familiarity of traditional POC lateral flow assays while providing the superior sensitivity and specificity provided by laboratory-based PCR testing.
Several companies are working in this area with platforms just launched or in late stage commercialisation, with numerous academic research programmes including those at the University of Washington working to develop platforms and systems in this area.
These platforms are looking to address some of the key challenges of bringing molecular assays to POC, by minimising the complexity and cost of the platform required to run the assays, removing the requirement for cold storage of the reagents and utilising lateral flow assays as the visualisation method for the assay result. There are many potential formats for capturing the amplicon from the amplification reaction, utilising a variety of different tags, including biotin, digoxigenin (DIG) carboxyfluorescein (Anti-Alarin Antibody/FAM), and FITC as well as utilising reporter probes.
BBI Solutions have a range of reagents that could be utilised in the development of a Nucleic Acid Lateral Flow assay including:
+ BA.GAB - Goat Anti-biotin conjugate
+ BA.MAB – Monocloncal Anti-biotin conjugate
The next step on the horizon for this sector is exploring the potential to create truly disposable molecular diagnostic platforms that are even lower cost and require no power source.
If you are interested in improving the sensitivity and specificity of your assay or want to explore how lateral flow could be utilised as a visual output for PCR, please contact us.