Patent ID: 8663923

Claim:
A method for detecting a target nucleic acid when present in a sample comprising: contacting the sample and a probe, the probe comprising a nucleotide strand that comprises a first fragment having a first closing sequence, a second fragment having a recognition sequence hybridizable to the target nucleic acid under hybridization conditions, a third fragment having a second closing sequence, and at least two markers such that one end of the nucleotide strand of the probe is free of a marker; and detecting hybridization of the probe and the target nucleic acid during or after amplification of the target nucleic acid when the target nucleic acid is present in the sample, wherein: in the absence of hybridization to the target nucleic acid, the first and second closing sequences are hybridized to each other in parallel under hybridization conditions such that the probe has a completely circular structure, thereby reducing detectability of the probe; and the first closing sequence or the second closing sequence comprises alpha nucleotides.