A competitive immunochromatographic assay based on a novel probe for the detection of mercury (II) ions in water samples

Mercury ions (Hg2+) are one of the most dangerous pollutants. Even at low concentration, it causes serious environmental and health problems. Current methods for the detection of Hg2+ in environmental samples are tedious and time consuming because they require sophisticated instrumentation and complicated sample pre-treatment processes. In this work, a novel probe with high selectivity towards Hg2+ was synthesized and a one step competitive immunochromatographic assay based on the probe for the detection of Hg2+ was developed and applied for water samples. The detection conjugate was immobilized on one end of the nitrocellulose membrane (detection line) and anti-BSA polyclonal antibody was immobilized on the other end of the membrane (control line). Hg2+ in samples competed with the probe to bind with immobilized detection conjugate. The visual detection limit of Hg2+ in spiked water samples was found to be about 1 ppb. The qualitative assay can be performed within 15 min. The advantages of the technique are rapidity, low cost and without the need of any equipment and complicated sample preparation. (C) 2010 Elsevier B.V. All rights reserved.