Patent ID: 6420115
Filing Date: 2002-07-16
Classification: C12Q

Abstract:
A method for assaying binding, said method comprising:providing a double-stranded nucleic acid comprising a target sequence, wherein said target sequence contains at least one purine base and at least one pyrimidine base; providing a probe comprising a nucleic acid sequence or a nucleic acid analog sequence at least partially complementary to said target sequence, wherein said nucleic acid sequence or nucleic acid analog sequence contains at least one purine base and at least one pyrimidine base; providing a cation; adding said probe, said double-stranded nucleic acid and said cation to a medium to provide a test sample containing a Watson-Crick triplex complex comprising said probe bound to said target sequence, wherein said Watson-Crick triplex complex further comprises at least one base triplet selected from the group consisting of A-T-A, A-U-A and G-C-G, and at least one other base triplet selected from the group consisting of T-A-T, U-A-T, T-A-U, U-A-U and C-G-C; irradiating said test sample with exciting radiation to cause said test sample to emit fluorescent radiation; and detecting an intensity of said fluorescent radiation, wherein said intensity identifies a binding between said probe and said target sequence.