Single quantum dot nanosensor used for detecting alkaline phosphatase and based on ligase amplification reaction catalytic assembly, and application

Abstract

The invention relates to a single quantum dot nanosensor used for detecting alkaline phosphatase and based on ligase amplification reaction catalytic assembly, and application. Firstly, an active signal of the alkaline phosphatase is identified and amplified by adopting a ligation reaction, specifically, when the alkaline phosphatase exists, a 3'-phosphoric acid tail end of a probe is subjected todephosphorylation through catalytic detecting to generate 3'-hydroxide radical tail end, then thermostable DNA ligase is used for triggering cyclic repeating connecting of a Cy5 probe and a biotin probe, and a plurality of Cy5-biotin double labeling signal probes are produced; and self-assembly of the signal probes is completed on the surface of a 605 quantum dot through the specific interactionof streptavidin-biotin, high efficient fluorescence resonance energy transfer (FRET) from the 605 quantum dot to Cy5 is achieved, and finally a single molecule fluorescence detection technology is used for detecting. On the contrary, when the alkaline phosphatase does not exist, fluorescence resonance energy transfer signals cannot be detected. The super high detection sensitivity can be achievedthrough only one thermostabilization ligase, and the limit of detection is as low as 5.63*10<-7>unit per milliliter.

Description

technical field [0001] The invention belongs to the field of enzyme activity detection, and in particular relates to a single quantum dot nanometer sensor assembled based on ligase amplification reaction catalysis for detecting alkaline phosphatase. Background technique [0002] The information disclosed in this background section is only intended to increase the understanding of the general background of the present invention, and is not necessarily taken as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. [0003] Alkaline phosphatase (ALP) is a hydrolase widely present in prokaryotes and eukaryotes, which can catalyze the removal of phosphate groups on phosphorylated proteins, nucleic acids, sugars and other biomolecules under alkaline conditions. It plays a key role in normal physiological functions such as cell division and bone formation; at the same time, the imbalance of intracellula...

AI Technical Summary

Problems solved by technology

However, the current detection method for alkaline phosphatase activity based on quantum dots still has the problems of low selectivity and low sensitivity.

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