Compound of molecular beacons for diagnosing lung cancers and preparation method thereof

Abstract

The invention discloses a compound of molecular beacons for diagnosing lung cancers. The compound comprises a magnetic nano microsphere and the molecular beacons adsorbed on the magnetic nano microsphere. The compound is characterized in that acc+Cct+Atca+Cgat+Tagcattaa is a circular sequence; the basic groups expressed with capitals in the circular sequence are the basic groups treated through locked nucleic acid modification; and the magnetic nano microsphere comprises magnetic nanoparticles and chitosan coating the surfaces of the magnetic nanoparticles. The compound has the beneficial effect of overcoming the defect that the molecular beacons in the prior art easily generate false positive signals during living cell detection and can resist degradation of nuclease in the living cells and detect miR-155 in the living cells, thus realizing diagnosis and differential diagnosis of the lung cancers.

Description

technical field [0001] The invention belongs to a molecular beacon for measuring or testing nucleic acid, in particular to a molecular beacon complex for measuring or testing miR-155. Background technique [0002] There are many detection methods for microRNA (microRNA, miRNA). Northern hybridization is a simple and reliable method to detect the expression level of miRNA in tissue cells, and the molecular size of miRNA can be detected by gel electrophoresis. The classic method is Northern-blot, but it requires a large amount of total RNA. Gene chip technology and real-time fluorescent quantitative PCR are applied to the systematic research and quantitative detection of miRNA, but the steps are cumbersome, the cost is high, and it is easily limited by the efficiency of reverse transcription. Methods such as fluorescence in situ hybridization (FISH) are relatively simplified methods, but there are relatively few in situ detection systems for miRNAs, mainly due to low copy and...

AI Technical Summary

Problems solved by technology

At present, the miRNA expression profile of lung cancer has been screened by gene chips and its function has been identified. In the present invention, miR-155, which is related to the occurrence and prognosis of lung cancer, is selected for detection, but when conventional molecular beacons are used for the detection and analysis of mRNA in living cells , due to the degradation and destruction of the molecular beacon skeleton by intracellular nucleases, false positive signals are often generated