A1 Refereed original research article in a scientific journal
Noncompetitive Chromogenic Lateral-Flow Immunoassay for Simultaneous Detection of Microcystins and Nodularin
Authors: Sultana Akter, Teemu Kustila, Janne Leivo, Gangatharan Muralitharan, Markus Vehniäinen, Urpo Lamminmäki
Publisher: MDPI AG, Basel, Switzerland
Publishing place: Basel
Publication year: 2019
Journal: Biosensors
Article number: 79
Volume: 9
Issue: 2
eISSN: 2079-6374
DOI: https://doi.org/10.3390/bios9020079
Web address : https://www.mdpi.com/2079-6374/9/2/79/html
Self-archived copy’s web address: https://research.utu.fi/converis/portal/detail/Publication/40724475
Abstract:
Cyanobacterial blooms cause local and global health
issues by contaminating surface waters. Microcystins and nodularins are
cyclic cyanobacterial peptide toxins comprising numerous natural
variants. Most of them are potent hepatotoxins, tumor promoters, and at
least microcystin-LR is possibly carcinogenic. In drinking water, the
World Health Organization (WHO) recommended the provisional guideline
value of 1 µg/L for microcystin-LR. For water used for recreational
activity, the guidance values for microcystin concentration varies
mostly between 4–25 µg/L in different countries. Current immunoassays or
lateral flow strips for microcystin/nodularin are based on indirect
competitive method, which are generally more prone to sample
interference and sometimes hard to interpret compared to two-site
immunoassays. Simple, sensitive, and easy to interpret user-friendly
methods for first line screening of microcystin/nodularin near water
sources are needed for assessment of water quality and safety. We
describe the development of a two-site sandwich format lateral-flow
assay for the rapid detection of microcystins and nodularin-R. A unique
antibody fragment capable of broadly recognizing immunocomplexes
consisting of a capture antibody bound to microcystins/nodularin-R was
used to develop the simple lateral flow immunoassay. The assay can
visually detect the major hepatotoxins (microcystin-LR, -dmLR, -RR,
-dmRR, -YR, -LY, -LF -LW, and nodularin-R) at and below the
concentration of 4 µg/L. The signal is directly proportional to the
concentration of the respective toxin, and the use of alkaline
phosphatase activity offers a cost efficient alternative by eliminating
the need of toxin conjugates or other labeling system. The easy to
interpret assay has the potential to serve as a microcystins/nodularin
screening tool for those involved in water quality monitoring such as
municipal authorities, researchers, as well as general public concerned
of bathing water quality.
Keywords:
noncompetitive immunoassay; cyanotoxin; microcystin; nodularin; lateral flow
Downloadable publication This is an electronic reprint of the original article. |  |
