Study On The Construction Of Guanine Fluorescence Probe And Its Application In Bioanalysis

BackgroundBiological analysis is of great significance in clinical diagnosis,forensic identification,food testing and research and development of new drugs.However,it is necessary to develop a new high sensitive detection method because of the low content of the target and the more impurities.Guanine base fluorescent probe has the advantages such as simple structure,fast reaction speed,low steric resistance and low cost.This study takes the signal amplification system constructed by G base fluorescent probe as an example to establish low background,good specificity,and easy to prepare low cost and high sensitive analytical methods,a series of biological molecule detection system is constructed to provide new ideas and methods for cancer and related basic research.This project plans to take the guanine-based fluorescent probe to solve the problems mentioned above through the reasonable design.A series of biological molecules detection systems were constructed by the establishment of low background,good specificity,easy to prepare low-cost and high-sensitivity analytical methods to provide new ideas and methods for cancer and related basic research.Objectives(1)A highly sensitive fluorescent probe was constructed based on G-base for signal amplification detection of mycobacterium avium complex;(2)A fluorescent probe based on G-base was constructed for signal amplification detection of thrombin;(3)A fluorescent probe based on G-base for immunoassay of tumor markers.Methods(1)The G-base fluorescent probe was constructed by using the repeated C-base of conserved sequences in HPV virus nucleic acid.When the target nucleic acid was present,the cyclic amplification reaction of exonuclease III was induced,thus the detection of target nucleic acid was realized.(2)A highly sensitive detection method for thrombin wasconstructed by combining G-base nucleic acid probe with nucleic acid polymerase-induced signal amplification by aptamer technique;(3)The G-base fluorescent probe was combined with immunoassay to construct the detection of tumor marker(PSA),and the method was used in the detection of serum samples.Results(1)The fluorescent probe based on G-base showed a good linear relationship for the detection of MAC nucleic acid in the range of 10 to 600 pM with the detection limit of8.46 pM;(2)The fluorescent probe based on G-base showed a good linear relationship for the detection of thrombin in the range of 20 to 250 pM with the detection limit of 14.25 pM,and the good linear relationship can also be found in complex samples.(3)The fluorescence sensor based on G-base fluorescence probe and immunoassay was used to detect tumor marker PSA in a linear range of 20-300 ng/ml,and the recovery rate in serum samples was about 104%-107%.Conclusions(1)The method of detection of MAC nucleic acid by fluorescent probe based on Gbase has lower detection background and better detection sensitivity;(2)The fluorescent probe based on G-base can be used to detect the content of thrombin in complex samples by signal amplification and this method has good selectivity and sensitivity.(3)The method based on G-base fluorescent probe and immunoassay can overcome the interference and influence of other impurities in serum samples,and the probe nucleic acid has good universality and can be directly used in immunoassay of other related substances.