Electrode Construction And Performance Research Of DNA Electrochemical Sensor For Scrub Typhus

The electrochemical biosensor has many advantages such as strong specific biometric detection,simple operation,rapid analysis,and less sample usage.In recent years,it has become a key research topic in various medical fields such as clinical medical diagnosis,environmental monitoring,and food science analysis.When researching and constructing biochemical sensors such as bioelectrochemical molecular DNA,combining some molecular detection technology methods and molecular amplification detection strategies and this technology can improve the detection performance of biosensors.For the key issues of DNA biosensor detection such as sensitivity,reproducibility,and stability,constructing biosensors from the perspective of nanomaterial modification of working electrodes or signal amplification strategies is an important breakthrough to solve this problem.This paper designs DNA electrochemical sensors from these two aspects,and the specific work is as follows:An electrochemical sensor based on layered nickel-iron hydrotalcite(Ni Fe-LDH)for rapid detection of tsutsugamushi DNA.The Ni Fe-LDH nanoflower-like structure is prepared by the traditional hydrothermal method,and a large number of gold nanoparticles are deposited on the structure by electrochemical deposition,which is conducive to the combination of the surface of the modified electrode and a large amount of probe DNA.At the same time,Ni Fe-LDH has a good catalytic oxidation effect on methylene blue(MB),which greatly enhances the electrical activity of MB.In addition,Ni Fe-LDH and competing strand DNA are loaded and fixed on the same electrode surface,shortening the distance between the two chemical reactions,and the efficiency performance of the catalyst is significantly improved.In addition,based on the modified electrode,a competitive signal amplification strategy was successfully designed for the detection of Scrub typhus DNA biosensor.In the experimental process of this strategy,only MB-labeled competing strand DNA is required to participate,avoiding the use of enzymes and avoiding problems such as high costs and harsh experimental conditions.This also simplifies the cumbersome steps in the DNA detection process.Closely linked to the high sensitivity and accuracy of detection performance,we have considered that the external environment may interfere with DNA detection,which may cause false positives and other problems.Therefore,a non-enzymatic proportional signal amplification strategy for electrochemical detection of Scrub typhus DNA was developed.The probe of the ferrocene electric signal molecule with the label is specifically opened,and the auxiliary group is assembled by the free body,the gold particle and the auxiliary chain labeled with the MB molecule form an auxiliary group,which is hybridized with the target chain After that,an electrochemical amplification signal is generated.Based on this method,a target chain can be bound to the auxiliary group with multiple MB,which provides a low detection limit method for the detection of the target.Compared with the previous single-signal electrochemical biosensors,this detection strategy has an inherent signal reference function,which can avoid signal fluctuations caused by the external microenvironment,and has strong anti-interference ability and reproducibility.The construction of the above two electrochemical sensors for detecting Scrub typhus DNA provides new research ideas for disease gene detection,and has good application prospects in clinical medical diagnosis.