Nucleic acid aptamer and derivatives thereof, screening method of nucleic acid aptamer, application of nucleic acid aptamer and derivatives in detecting human biliary duct carcinoma cell line

Abstract

The invention discloses a nucleic acid aptamer with a sequence containing DNA (deoxyribonucleic acid) segments shown by any of a sequence 1 and a sequence 2. The nucleic acid aptamer can also be derivatives obtained by various similar sequences high in homology or the sequence. The invention further discloses a screening method of the nucleic acid aptamer. The method includes: synthesizing a random single-strand DNA library and a primer, performing Cell-SELEX screening and PCR (polymerase chain reaction) library amplification, preparing a DNA single-strand library, and obtaining the nucleic acid aptamer through repeated screening, negative screening and several rounds of screening. The nucleic acid aptamer and derivatives thereof can be applied to recognizing human biliary duct carcinoma cell line QBC-939 or preparing a reagent box for detecting the human biliary duct carcinoma cell line QBC-939, has affinity and specificity higher than anti-keratin antibodies, and is free of immunogenicity, capable of being chemically synthesized, small in molecular weight, stable, easy to store and mark, and the like.

Description

technical field [0001] The present invention relates to a nucleic acid aptamer and its screening and application, in particular to a nucleic acid aptamer which can be used to detect human cholangiocarcinoma cells and its screening method and application. Background technique [0002] Nucleic acid aptamers (aptamers) are single-stranded oligonucleotides (ssDNA or ssRNA) that can specifically bind to target substances and are screened by the systematic evolution of ligands by exponential enrichment (SELEX). Nucleic acid aptamers have similar functions to antibodies, but have more advantages than antibodies, with higher affinity and specificity; no immunogenicity; chemical synthesis, low cost; labeling; good stability, easy Preservation and other advantages. The target molecules of nucleic acid aptamers are more extensive, including metal ions, amino acids, nucleic acids, polypeptides, proteins, and expanded from single targets to complex targets such as complete virus particl...

AI Technical Summary

Problems solved by technology

Hilar cholangiocarcinoma is very difficult to operate because of its special location, invasive growth, and close relationship with hilar blood vessels.

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