The CDIATM Cylindrospermopsin Colloidal Gold Test Strip is an immunochromatographic test for the detection of cylindrospermopsin in drinking and recreational waters.
The test is based on the recognition of Cylindrospermopsin by specific antibodies. The toxin conjugate competes for antibody binding sites with Cylindrospermopsin that may be present in the water sample. The test device consists of a vial containing specific antibodies for Cylindrospermopsin labeled with a gold colloid and a membrane strip to which a conjugate of the toxin is attached. A control line, produced by a different antibody/antigen reaction, is also present on the membrane strip. The control line is not influenced by the presence or absence of Cylindrospermopsin in the water sample and, therefore, should be present in all reactions. In the absence of toxin in the water sample, the colloidal gold labeled antibody complex moves with the water sample by capillary action to contact the immobilized Cylindrospermopsin conjugate. An antibody-antigen reaction occurs forming a visible line in the test area. The formation of two visible lines of similar intensity indicates a negative test result, meaning the test did not detect the toxin at or above the cut-off point established for the toxin. If Cylindrospermopsin is present in the water sample, it competes with the immobilized toxin conjugate in the test area for the antibody binding sites on the colloidal gold labeled complex. If a sufficient amount of toxin is present, it will fill all of the available binding sites, thus preventing attachment of the labeled antibody to the toxin conjugate, therefore preventing the development of a colored line. If a colored line is not visible in the test line region, or if the test line is lighter than the control line, Cylindrospermopsin is present at a level of concern. Semi-quantitative results in the range of 0-10 ppb can be obtained by comparing the sample test strip appearance to the appearance of test strips from solutions of known Cylindrospermopsin concentrations (control solutions). Concentrated Cylindrospermopsin standards can be used to prepare Cylindrospermopsin controls.
Most of the world’s population relies on surface freshwaters as its primary source for drinking water. The drinking water industry is constantly challenged with surface water contaminants that must be removed to protect human health. Toxic cyanobacterial blooms are an emerging issue worldwide due to increased source water nutrient pollution caused by eutrophication. Cylindrospermopsin is a toxin produced by several different types of cyanobacteria (blue-green algae) and has been found in fresh water throughout the world. Certain strains of Cylindrospermopsis raciborski (found in Australia, Hungary, and the United States), Umezakia natans (found in Japan), and Aphanizomenon ovalisporum (found in Australia and Israel) have been found to produce Cylindrospermopsin. The production of Cylindrospermopsin seems to be strain specific rather than species specific.Acute poisoning of humans and animals constitutes the most obvious problem from toxic cyanobacterial blooms, and in several cases has led to death. Human and animal exposure to these toxins can occur through the ingestion of contaminated water, through drinking or during recreational activities in which water is swallowed, or food, such as fish. Dermal contact with Cylindrospermopsin may occur during showering or bathing, or during recreational activities such as swimming or boating. These toxins mediate their toxicity by inhibiting liver function and are potent inhibitors of protein synthesis and glutathione, leading to cell death.To protect against adverse health effects, the U.S. Environmental Protection Agency (EPA) has established health advisories for Cylindrospermopsin in drinking water: (1) For children pre-school age and younger (less than six years old), 0.7 µg/L (ppb). (2) For school-age children and adults, 3.0 µg/L (ppb). The CDIATM Cylindrospermopsin Colloidal Gold Test Strip for water is a rapid immunochromatographic test designed solely for use in the qualitative screening of Cylindrospermopsin in fresh water. A rapid cell lysis step performed prior to testing is required to measure total Cylindrospermopsin (dissolved, or free, plus cell-bound). The CDIATM Cylindrospermopsin Colloidal Gold Test Strip provides only preliminary qualitative test results. If necessary, positive samples can be confirmed by ELISA, HPLC or other conventional methods.