The lateral flow (Immuno) assay is one of the old diagnostic platforms that was discovered and later developed in the 1980s. With the evolution of technology and the passage of time, a panel of diversity has been brought towards the Lateral flow (Immuno) Assay. For a wide range of target analytes, lateral flow test strips based on immunochromatographic principles are available. The first tests were performed to diagnose human chorionic gonadotropin (hCG). As it is above-mentioned that this diagnostic platform is influenced by modern technology therefore Lateral Flow (Immuno) assay is getting integrated with the technology and diverse tools such as Electrochemical and optical transducers and Wireless data transfer as well. The advancement and expansion of sensitive, multianalyte, and quantitative assays that will remain competitive with a few of the diagnostics being used in the laboratories show that they are ahead of time and advanced.
The SWOT Analysis for the Lateral flow Immuno Assay gives the description of Strengths, weaknesses, opportunities, and strengths in great detail. First of all, discussing the strengths of the Lateral flow Imuuno assay; the first one is that it is used almost at every place where the point of care is needed such as in clinics, emergency rooms, physicians examination room, testing organic compounds, diagnosing processes, checking the existence or absence of various infectious hazards and diseases or even in the food and feed industries, phytopathological settings or adulteration with unfavorable components are common. It is also the most preferred and most used testing format in the field of biowarfare, forensics, and law enforcement. Having said that, an independent test is performed on the samples whose results come out positive. Also, for developing countries, the Lateral Flow Immuno Assay is most used as there is no need for strips to be refrigerated. Further, the interpretation of the results is adequate. Lateral Flow Immuno Assays are disposable and this means that they can only be used once and later discarded.
With strengths, the weaknesses also exist. First of all, LFAs cannot be washed as they are only a one-step assay and it is highly not advised to pre-block the strips. The reason is that pre-blocking or even washing them can destroy the wetting and well-balanced hydrophobicity properties that can result in more adverse possibilities. Another weakness of the Lateral Flow Immuno Assays is that they cannot be mishandled as the kit has a dropper. The use of a dropper is meticulous and mishandling them can lead to errors in the result. Coming to the volumes of the mounting device the restriction can be found there. The volumes are restricted to 100 μL and extend to 1 milliliter. Exceeding the limits of the volumes results in the deterioration of the immuostrip.
The Opportunities in the Lateral Flow Immuno Assays are pertaining towards the off-laboratory applications. For instance, we see that pregnancy tests are easily done at home. Home testing has gained so much potential that it can be easily performed at home and the results can be obtained. Moreover, non-prescription tests are also available that can be gotten either through the internet or some pharmacy. The opportunities of Lateral Flow assay are increasing day by day as they are the most topmost diagnosing test format to obtain the fastest results such as in emergency wards, clinics, law enforcement, checking absence or presence of pathogens, forensics, and much more. Another opportunity is related to a weakness of volume that has been described earlier. Even though there is a limitation in the volumes of the matrix such as blood, sweat, serum, urine, plasma, etc. it is an opportunity to obtain the most accurate results by meeting the adequate sensitivity of the present analyte. If the target analyte is present in the matrix of the Lateral Flow Immuno Assays (LFAs), the limited volume doesn’t matter; rather, it is more recommended.
Despite the fact that Lateral Flow Immuno Assays have their own strengths, weaknesses, and opportunities there is another factor of SWOT analysis that must not be forgotten and that is the threats to Lateral Flow Immuno Assays. As it is known that there are many technology-based test systems and it has become a part of this industry, therefore, the hardware and software of these systems are not costly rather they are easily available in the market. To actively demonstrate it in the form of words, it can be seen that chromatography-mass spectrometry and liquid chromatography-mass spectrometry require personnel, and the process of the miniaturization of the devices has resulted in their use rather than the Lateral Flow Immuno Assays. Also, the lab-on-a-chip testing format is becoming more common and usable than the lateral flow immuno assays devices and diagnosing format. Moreover, the enzyme immuno assays are always performed in the laboratory where the technical personnel or staff is present. But now considering the threat of hardware and technology the tests can be performed by using hardware in the automated set-ups that are also known by the name of ELISA Robots.
Medical applications in Western countries can contribute to the provision of incorporating the LFA in a lab-on-a-chip design. Furthermore, a clinical laboratory is frequently nearby, providing additional services. Costs, on the other hand, will skyrocket. Lateral Flow Immuno Assay are the preferred place for true off-laboratory applications at the point of care/need in resource-limited settings. Strips can be kept at room temperature for an extended period of time. That being said, high classification elements must be readily accessible, and visual qualitative on-off or semiquantitative results obtained using, for example, the bar code layout or a reflectometer must be adequate. New frameworks have been proposed to increase sensitivity by strengthening the signal with colloidal gold nanoparticles or by combining gold nanoparticles with horseradish peroxidase, which consequences in signal amplification. It has also been outlined how to diagnose both antigens and antibodies by using two conjugate pads for the qualitative determination of two proteins. However, LFAs are the most preferred and used testing format for the diagnosis.
References
https://pubmed.ncbi.nlm.nih.gov/18696055/
https://www.researchgate.net/figure/Advantages-and-disadvantages-of-the-lateral-flow-assay_fig5_304624146
https://link.springer.com/article/10.1007/s00216-008-2287-2
https://viroresearch.com/lateral-flow-assay-advantages-disadvantages/
