Cascade amplifying-strategy biomolecule detecting method based on self-locking aptamer probe

Abstract

The invention discloses a cascade amplifying-strategy biomolecule detecting method based on a self-locking aptamer probe. The probe at least comprises two parts of an aptamer sequence of a 3(minute) terminal having specific recognition on a target and a signal transduction sequence of a 5(minute) terminal, wherein the signal transduction sequence of the 5(minute) terminal is hybridized with a part of the aptamer sequence to form a stem-loop structure of the 5(minute) terminal, and the signal transduction sequence of the 5(minute) terminal comprises a recognition site of Cech endonuclease. The probe combines strand displacement amplification (SDA) with a double-exponential rolling circle amplification (DE-RCA) strategy to achieve ultra-sensitive and high-specific detection on protein-PDGF-BB and micromolecule-adenosine, wherein the detection limit reaches 3.8*10<-16>mol / L and 4.8*10<-8>mol / L respectively.

Description

technical field [0001] The invention relates to the technical field of nucleic acid detection, in particular to a highly sensitive and specific detection method for proteins and small molecular substances using a self-locking aptamer probe-based cascade amplification strategy. Background technique [0002] Aptamers are a class of artificially synthesized, short single-stranded oligonucleotide sequences that are often used in biosensing, diagnosis, and therapy. Aptamers usually have specific and compact secondary or tertiary structures, and have high affinity and selectivity for their corresponding targets. Compared with antibodies or antibody fragments, aptamers are stable, easy to synthesize and modify, and have a wide range of targets, including proteins, small molecules, metal ions, and even cells. Therefore, aptamers have been widely used in the construction of molecular probes. [0003] Aptamer-based molecular probes mainly include two parts: aptamer sequence and sign...

AI Technical Summary

Problems solved by technology

However, due to the short length of the blocking strand (12-15nt), the instability of the double-stranded structure will cause the blocking strand to leak (fall off from the aptamer probe), which in turn leads to the generation of interfering signals

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