Enhancing the lateral-flow immunoassay for viral detection using an aqueous two-phase micellar system

Abstract

Availability of a rapid, accurate, and reliable point-of-care (POC) device for detection of infectious agents and pandemic pathogens, such as swine-origin influenza A (H1N1) virus, is crucial for effective patient management and outbreak prevention. Due to its ease of use, rapid processing, and minimal power and laboratory equipment requirements, the lateral-flow (immuno)assay (LFA) has gained much attention in recent years as a possible solution. However, since the sensitivity of LFA has been shown to be inferior to that of the gold standards of pathogen detection, namely cell culture and real-time PCR, LFA remains an ineffective POC assay for preventing pandemic outbreaks. A practical solution for increasing the sensitivity of LFA is to concentrate the target agent in a solution prior to the detection step. In this study, an aqueous two-phase micellar system comprised of the nonionic surfactant Triton X-114 was investigated for concentrating a model virus, namely bacteriophage M13 (M13), prior to LFA. The volume ratio of the two coexisting micellar phases was manipulated to concentrate M13 in the top, micelle-poor phase. The concentration step effectively improved the M13 detection limit of the assay by tenfold from 5 × 108 plaque forming units (pfu)/mL to 5 × 107 pfu/mL. In the future, the volume ratio can be further manipulated to yield a greater concentration of a target virus and further decrease the detection limits of the LFA.FigureA schematic representation of concentrating viruses with an aqueous two-phase micellar system containing Triton X-114 surfactant prior to the detection of the virus through the lateral-flow immunoassayElectronic supplementary materialThe online version of this article (doi:10.1007/s00216-010-4213-7) contains supplementary material, which is available to authorized users.

Development of quantitative radioactive methodologies on paper to determine important lateral-flow immunoassay parameters

“…1 Due to the unique combination of specificity, speed, simplicity, and low cost, LFA has seen extensive use in many areas, including medical diagnostics, food safety, and defense against bio-warfare agents. [20][21][22][23][24][25][26] These innovations improve the applicability, robustness, and accuracy of LFA, but at the same time, increase the complexity of the technology. Some recent key innovations in these fields include work with two-dimensional paper networks, 6-14 microfluidic paper-based analytical devices (µPADs), [15][16][17][18][19] and equipment-free thermodynamic target concentration.…”

Development of a Nanoparticle-based Lateral Flow Strip Biosensor for Visual Detection of Whole Nervous Necrosis Virus Particles

“…Most experimental investigations of lateral flow assays are focused on the end product, characterizing only a few test system parameters 24 . However, lateral flow assays sensitivity on virus detection has been estimated from 19% to 96% 25 . Thus, the low sensitivity in virus detection with lateral flow assays restricts their application as reliable assays for on-site analysis.…”

Miniaturization of aqueous two‐phase extraction for biological applications: From micro‐tubes to microchannels

“…Other analytical techniques such as immunoassays have also been reported to take advantage of ATPE in order to enhance sensitivity, in particular, using P‐S systems to process wine and beer samples for the detection of the mycotoxins ochratoxin A and aflatoxin B1 . As a different approach and going towards miniaturization, ATPE has also been used together with lateral‐flow immunoassays for sample processing and concentration in order to enhance the detection of target molecules such as proteins and virus‐like particles .…”