Research And Application Of Biosensors Based On Metal Ions And Graphene Oxide

Bioinformatics,as a typical representative of interdisciplinary disciplines,covers computer science,biology,mathematics,chemistry,physics and other disciplines.DNA computing is a branch of bioinformatics.Compared with traditional electronic computers,DNA computing has the advantages of fast parallel processing speed and high molecular parallelism,so it has attracted wide attention.Biosensor is a platform for the application of DNA computing theory to practice.Although the research of biosensor started late,it has also developed rapidly in recent decades.Nowadays,with the help of advanced scientific ideas and means,the occurrence of various diseases and the accompanying random system are becoming clearer and clearer.Accordingly,many targeted detection methods have been produced.This condition opens a new door for the design and development of biosensors.In addition,besides detecting specific targets,biosensors can also constitute simple logic elements,which can promote the development of DNA computing.Firstly,we summarized the research background and significance of bioinformatics,DNA computing,biosensors and some pathogenic mechanisms,and then summarized the research status of biosensors at home and abroad by functional classification.This part is the basic theoretical condition of biosensor design.Secondly,the structure,research difficulties and performance indicators of biosensors are described in detail.Firstly,the structure of biosensors is introduced.On this basis,the emphasis of biosensor research is explained.Then,the indicators of biomarker performance are introduced,which provides a scientific basis for the optimization of our subsequent experiments and the determination of which properties of biosensors.After that,the characteristics and special substances commonly used in biosensors at the biological level,as well as some commonly used detection methods are introduced.It mainly includes strand displacement,stem-ring structure with signal amplification function and some enzymes which are most commonly used in biological research.The detection methods include electron microscopy imaging,electrophoresis and fluorescence detection.This part is an indispensable technical support for our biological experiments.Based on that,we first introduce a multi-functional molecular probe based on metal ion-mediated base mismatch.The innovation of this design is that mercury and silver ions can be simultaneously detected by the same model,and an OR logic gate is constructed.In the first step,we introduced the principle of the model and how to construct OR logic gates.Then we carried out preliminary feasibility verification by means of computer simulation.Then we carried out orthogonal experiments,optimization of various factors,target selectivity experiments,specificity experiments,actual sample detection and other aspects of research by means of biological experiments,and carried out a detailed measurement of the sensor performance.On the other hand,we have designed a biological logic model based on graphene oxide,a new nanomaterial.This part of the design principle is based on the fact that graphene oxide can adsorb single-stranded DNA and quench fluorescence.We have constructed a YES logic gate and an AND logic gate respectively.Similar to the previous part,the designed graphene oxide-based model has been verified by computer simulation experiments and biological experiments.In summary,the results show that:1.The fluorescence abnormality of metal ion-based sensors under polar acid or alkali conditions can be used to preliminarily determine whether water is strong acid or alkaline in actual sample detection.The experiment proves that the target concentration of metal ion-based sensors is linearly correlated with the fluorescence intensity in terms of target selectivity,and its function formula can be used to detect unknown target concentration.In the actual sample detection experiment,the recovery range obtained accords with the prescribed range,which proves that the designed sensor can be applied in practice.By comparing with other methods,the advantages of this design are convenient,fast and high sensitivity.2.The biological logic model based on graphene oxide was preliminarily proved to be feasible by NUPACK and electrophoresis experiments.The fluorescence experiment further proved that graphene oxide has the ability of adsorbing single chain and quenching fluorescence.Electron microscopy and experimental experience show that graphene oxide is easier to break into water than graphene,and the longer the breaking time,the more stable the colloid,the better the experimental results.Generally speaking,this paper tests the feasibility,performance,optimum conditions and practical sample application ability of the biosensor in various ways,and introduces new materials for experiments,which may provide some new ideas for the research of biosensor.Finally,we analyzed and summarized the two sensors designed,summarized the innovations and shortcomings of this study,and prospected the future development of biosensors.