The Construction Of Fluorescent Probes Based On G-triplet And MOFs Materials And Study Of Nucleic Acids

Nucleic acids are essential biologically active molecules in genetic and pathological analysis.the detection and determination of nucleic acids are particularly necessary for the early detection and medical diagnosis of cancer.Therefore,in this paper,several different highly sensitive fluo-rescent biosensors are constructed based on G-triplet and metal organic framework materials for detecting specific DNA or miRNA.The specific research is as follows:1. Enzyme-free and label-free amplification strategy based on G-triplet for fluo-rescence detection of HIV-DNABased on the G-triplet structure and catalytic hairpin self-assembly amplification?CHA?technology,the HIV-DNA fluorescence detection system have developed.Hairpin molecule 1?H1?can act as a triggering molecular probe that binds to HIV-DNA.The G-triplex produced by hybridization with the target can bind to thioflavin T?ThT?,thereby making ThT fluorescent signal increased significantly.This method not only has good selectivity,but also has a wide linear range,with a detection limit of 33 p M.In addition,this method does not require complex labeling enzymes.It is practical and simple.2. A bioprobe based on metal organic framework material UiO-66-NH₂ and triple helix molecular beacon for fluorescence detection of miRNAIn this work,we first assemble the DNA triple helix molecule into the R2-MOFs complex by covalent interaction with the MOFs material.In the absence of miRNA-203,the fluorescence of the dye FAM modified in P1 is quenched by the MOFs and the fluorescence signal is reduced.In the presence of miRNA-203,due to the hybridization of P1 and miRNA-203,the FAM is away from the MOFs material,and the fluorescence of FAM rises.This method is highly selective for miRNAs of the same ethnicity.At the same time,the proposed fluorescent probe has also been applied to the detection of actual biological samples,indicating that it can be expected to be further used in clinical diagnosis.3. A bioprobe based on metal organic framework material ZIF-8 for ratiometric fluorescence amplification detection of miRNAIn this work,we developed a biological probe based on the metal organic framework material ZIF-8 for the ratiometric fluorescence amplification detection of miRNA.When the Y-MOFs material encounters an acidic environment,the MOFs material will decompose,releasing molecular beacons Y1 and Y2.The target first reacts with Y1 to eliminate the fluorescence resonance energy transfer effect in Y1 and form a ratiometric detection effect.The Y1-miRNA-21 complex continues to react with Y2 to form a ratiometric amplification detection effect on the target.This method can achieve efficient and sensitive detection of the target,with a detection limit as low as 27 p M.At the same time,the proposed fluorescent probe is also used in human serum and cell lysate for detection,indicating that it can provides a better reference for clinical diagnosis and detection of miRNA.