MIP-based solid phase extraction cartridges combined with MIP-based sensors for the detection of microcystin-LR

Microsystin-LR is one of the most widespread and dangerous toxins produced by the freshwater Cyanobacteria. The contamination of water supplies with microcystin-LR has been reported in several areas around the world and the development of an easy-to-use, rapid, robust and inexpensive sensor for this toxin is urgently required. In this work an artificial receptor for microcystin-LR was synthesised using the technique of molecular imprinting. The composition of the molecularly imprinted polymer (MIP) was optimised using computer modelling. The synthesised polymer was used both as a material for solid-phase extraction (SPE) and as a sensing element in a piezoelectric sensor. Using the combination of SPE followed by detection with a piezoelectric sensor the minimum detectable amount of toxin was 0.35 nM. The use of MIP-SPE provided up to 1000 fold preconcentration, which was more than sufficient for achieving the required detection limit for microcystin-LR in drinking water (I nM). This work is the first example where the same MIP receptor has been used successfully for both SPE and the corresponding sensor. (C) 2002 Elsevier Science B.V. All rights reserved.