Methods for producing nucleic acid hybridization probes that amplify hybridization signal by promoting network formation

摘要

This invention describes methods for generating nucleic acid probes that improve the sensitivity of hybridization assays. The sensitivity increase results from structural modifications of nucleic acids that promote network formation during hybridization with the result that a single target molecule becomes attached to a complex of many probe molecules. The structural modification involves fragmentation of the probe nucleic acid followed by joining the fragments together such that their order and orientation and number is altered from the original probe molecule. The result is the generation of permuted probe libraries. Individual members of permuted probe libraries can be isolated, amplified and perpetuated. Libraries can be prepared with additional sequences not present in the target and the fraction of the library made up by such sequences controlled. Probes for different targets can incorporate different non-target sequences in hyper-molar quantities permitting sensitive detection of multiple hybridization targets in the same sample.