Use of fluorescent europium chelates as labels for detection of microcystin-LR in Taihu Lake, China

A method using the time-resolved fluorescence technology to establish a highly sensitive microcystin-LR (MC-LR) indirect competitive immunoassay was proposed in this work. This method was used to monitor the MC-LR level in source water and treated drinking water from Taihu Lake. Algae in the water samples were removed by centrifugation, and the MC-LR level was quantified using this method. Testing results showed that the sensitivity of this method was 0.01 μg/L, and the dynamic measuring range was from 0.05 to 2 μg/L. The average recovery was 115%, and the variation (CV) within and between different batches were 7.3% and 9.7%, respectively. Testing results also indicated that this time-resolved fluoroimmunoassay was sensitive and accurate in measuring MC-LR level, especially for quantitative analysis MC-LR level in bulk water.