Patent ID: 8883994

Claim:
The switchable nucleic acid aptamer probe, comprising: a probe body comprising a nucleic acid aptamer fragment capable of specifically recognizing target tumor cells and a nucleic acid fragment capable of hybridizing with said nucleic acid aptamer fragment with a complementary sequence of 6˜12 base pairs; a flurorescence generating unit and a fluorescence quenching unit respectively connected to two ends of said switchable nucleic acid aptamer probe; and a connecting fragment of a length of 7˜15 nm connecting said nucleic acid aptamer fragment and said nucleic acid fragment to form a hairpin structure, wherein an ability of said nucleic acid fragment for competitively hybridizing with said nucleic acid aptamer fragment is weaker than an ability of said target tumor cells for interacting with said nucleic acid aptamer fragment, wherein said nucleic acid aptamer fragment is tumor-targeted nucleic acid aptamer selected from a technology of systematic evolution of ligands by exponential enrichment, wherein said nucleic acid aptamer fragment is selected from a group consisting of [a nucleic acid aptamer sequence 1 which is capable of specifically recognizing human T Cell acute lymphoblastic leukemia cell lines,] a nucleic acid aptamer sequence 1 which is capable of specifically recognizing Human Burkitt's lymphoma cell lines, and a nucleic acid aptamer sequence 2 which is capable of specifically recognizing mouse hepatoma cell lines; [wherein a nucleotide sequence of said nucleic acid aptamer fragment 1 is: SEQ ID NO: 3: 5′-ATC TAA CTG CTG CGC CGC CGG GAA AAT ACT GTA CGG TTA GA-3′;] wherein a nucleotide sequence of said nucleic acid aptamer fragment 1 is: SEQ ID NO: 5: 5′-AAC ACC GTG GAG GAT AGT TCG GTG GCT GTT CAG GGT CTC CTC CCG GTG-3′; and wherein a nucleotide sequence of said nucleic acid aptamer fragment 2 is: SEQ ID NO: 6: 5′-AGT CCA TTT TAT TCC GTT AAC CTC TGA ATA TTT ATG GAC-3′.