[The use of ultrasensitive time-resolved fluoroimmunoassay for rapid detection of microcystin LR].

Objective: In order to provide a rapid and selectivity method for the determination of microcystin LR (MCLR).

Methods: An indirect competitive time-resolved fluoroimmunoassay (TRFIA) was developed. MC-LR-BSA was coated by physical adsorption onto the microtitre plate, MC-LR or sample with MC-LR as a competitor. Both them were incubated with limited anti- MC-LR antibody. and a goat antirabbit IgG-Eu3+ conjugate was used as a tracer.

Results: The sensitivity of MC-LR-TRFIA was 0.01 microg/L, and the recovery rate was 99.7%. RSD of CBL-TRFIA were 3.9%. The sensitivity of MC-LR -TRFIA provided a linear reaponse from 0.01 - 20 microg/L, with ED50 of 0.57 microg/L or ED80 of 0.16 microg/L and ED20 of 1.70 microg/L. The cross reactivity of the MC-LR-TRFIA with MC-LF and MC-RR was 0.73% and 35%. Both MC-LR-TRFIA and MC-LR-ELISA test were applied for the quantitative measurement of MC-LR in the same samples, and the coefficient of correlation was 0.958.

Conclusion: The method is suitable to determine MC-LR in water samples.