Towards Lateral Flow Quantitative Assays: Detection Approaches

Abstract

Point-of-care (POC) or bedside analysis is a global trend in modern diagnostics. Progress in POC testing has largely been provided by advanced manufacturing technology for lateral flow (immunochromatographic) test strips. They are widely used to rapidly and easily control a variety of biomarkers of infectious diseases and metabolic and functional disorders, as well as in consumer protection and environmental monitoring. However, traditional lateral flow tests rely on visual assessment and qualitative conclusion, which limit the objectivity and information output of the assays. Therefore, there is a need for approaches that retain the advantages of lateral flow assays and provide reliable quantitative information about the content of a target compound in a sample mixture. This review describes the main options for detecting, processing, and interpreting immunochromatographic analysis results. The possibilities of modern portable detectors that register colored, fluorescent, magnetic, and conductive labels are discussed. Prospects for further development in this direction are also examined.

Microfluidic Point-of-Care Devices: New Trends and Future Prospects for eHealth Diagnostics

“…The results are obtained through a smartphone application, which reads the colorimetric results from the strip and provides a positive or negative result based on a cutoff threshold. This biosensing approach has been the subject of several papers, where tools for registration, transfer, and analysis of assays data were discussed [93][94][95][96]. A summary of the patient details and a description of the test taken are given in Figure 9B.…”

Six decades of lateral flow immunoassay: from determining metabolic markers to diagnosing COVID-19

“…Detection and control of infectious diseases is a serious healthcare issue. LFIA testing can be successfully used in diagnostics of infectious diseases [6] , [16] – [18] , [22] , [32] .…”

“…One of the key trends of development of the versatile LFIA technology is the designing of test systems in a multiplex (multi-purpose) format, which allows detection of several bacterial or viral targets at a time in a single test. This technology is a novel diagnostic approach providing wide opportunities for verification of causative agents [6] , [8] , [17] , [32] , [50] ( Table 1 ).…”

“…When molecular markers of an infectious process are detected using LFIA, this usually requires confirmation by an independent method. Therefore, immunoassay technologies are suitable mostly for primary screening [6] , [8] , [17] , [72] . In addition, despite the obvious attractiveness of the LFIA formats, their limitations a great while held back the expansion of the practical use of these diagnostic platforms for clinical laboratory diagnostics ( Table 2 ).…”

“…The growing popularity of these test systems for medical care or diagnostics in developing countries, medical institutions, emergency situations, as well as for individual use by patients monitoring their health at home are the major factors that contribute to the continuous development and improvement of this method and to the invention of new-generation formats [2] , [6] – [8] .…”