The Application Of Voltammetric Analysis In Monitoring The Process Of Gene Amplification And Detecting The Malachite Green And Diethylstilbestrol

This thesis mainly focused on the application of electrochemical voltammetrictechniques in the field of food quality control and environmental monitoring. Thispaper could divide into two parts: one is the application of voltammetric techniques tomonitor the processes and the results of DNA amplification in the analysis of foodand microorganisms; the other is the rapid detection of malachite green (MG) anddiethylstilbestrol (DES) using the electrochemical sensors.Integrating loop-mediated isothermal amplification (LAMP) and high sensitivevoltammetric techniques, LAMP solved many problem of the molecular biology ofnucleic acids and made rapid and inexpensive diagnosis to the possible.First, electrochemical sensor with the character of easy renewal, easy modificationand reproducibility, were fabricated by conventional method described in previous.And then, established a method of LAMP amplified the genetic fragments whichextracted from Escherichia coli (E. coli). On this basis, our research not only studiedthe voltammetric behavior of the endogenous substance in the LAMP mix system, butalso the changes of voltammetric parameters and the mechanism of electrode as theprogress of LAMP reaction.In the following, we selected the suitable electrochemical probe as the indicator，to study the relationship between the response of electrochemical and the content ofinitial template DNA in the LAMP mix system. At last, we describe here a novelstrategy for recording the reaction process of LAMP by monitoring the voltammetricresponse of dGTP. In inversion, the decrease of the ipaof dGTP was used tocharacterize the reaction process of LAMP. The results indicate that the protocolintegrated LAMP and voltammetric techniques can be used for not only qualitativegene discrimination but also quantitative gene assay in a wide range. The presence of DES and MG in the environment, e.g. fishery water, has becomea concern because they could lead to serious ecological problems. Moreover, it hasbecome an important factor affecting food quality, safety and the competitiveness inthe international market. So, it seemed very important to fabricate some relateddetective method. The paper studied the mechanism of the voltammetric response ofthe two substances in the working electrode, and applied the new method to thedetection of the target substances in water samples, and achieved some satisfactoryresults. First, prepared with the paste electrode with good electrical and chemicalproperties, and then study of the electrode mechanism of the MG and DES in relatedelectrode. According to these optimized testing conditions, the best operatingparameters will be used in the actual sample detection. The results of this researchwere expected to be used as the rapid methods for detecting drug residues in food andthe environment.