DETECTION OF TOXIC ALGAE

摘要

The invention relates to sequence-specific capture probes for detecting toxic algae by means of selective hybridisation of a complementary nucleic acid sequence which unequivocally characterises the algae to be detected and is in the form of special base sequences which bind to complementary sequences of the rRNA of the small 18S sub-unit or the large 28S sub-unit of the algae-specific ribosome or the single-strand DNA. The invention also relates to an electrochemical detection method for rapidly detecting toxic algae in situ in a liquid sample using at least one immobilised, sequence-specific capture probe (7). According to the inventive method, an auxiliary probe (12) is used to enable or to improve a sandwich hybridisation of the nucleic acid sequence (10) which is characteristic of the algae, and a marked detector probe (11) is used to easily identify said sandwich hybridisation. Both additional probes (11, 12) are located close to the sequence-specific capture probe (7) with as small a distance as possible between sequences, with a maximum difference of between 150 and 200 bases. The invention further relates to an arrangement for carrying out the detection method said arrangement comprising a complete set of disposable biosensor chips (1) which have a three-electrode system (4, 5, 6) and are pre-coated by the corresponding capture probes, and a hand-held display appliance and to the use of said arrangement as an early warning system for toxic algae.