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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 × 10(8) plaque forming units (pfu)/mL to 5 × 10(7) 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.

SUBMITTER: Mashayekhi F

PROVIDER: S-EPMC2990019 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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

Mashayekhi Foad F Chiu Ricky Y T RY Le Alexander M AM Chao Felix C FC Wu Benjamin M BM Kamei Daniel T DT

Analytical and bioanalytical chemistry 20100924 7-8

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 s ...[more]

PMID: 20865404

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

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

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