| Electrochemical scanning microscopy(SECM)is a new type of scanning probe microscope with high temporal resolution,which was proposed by American electrocutor Bard and 1989.Because of its "chemical sensitivity",it can not only characterize the surface morphology of the test sample,more importantly,it also can distinguish its electrochemical activity.Electrochemical scanning microscopes make up for the lack of other scanning techniques(such as scanning tunneling microscopy and atomic force microscopy).For biological cells that are immobilized on the detection substrate and have a charge or generate an electroactive substance,it can directly detect the sample Electroch-emical activity information.Electrochemical scanning microscopy has good selectivity and high detection sensitivity,and it also can achieve real-time online monitoring and analysis of biological system without damage.It has a unique research and application advantages in the biological system morphology and micro-regional chemical information analysis.The experimental study will select the typical bacterial bacteria in the food industry(Staphylococcus aureus membrane),exploring the single bacterial bacteria in the process of bacteria produced by the redox activity of the enzyme which in the bacterial membrane formation and growth process,and investigating the changes of the redox activity in the process of bacterial membrane formation in order to explore the effective way to control the bacterial membrane pollution in the food industry.In this paper,the whole growth process of the bacterial membrane on the coverslip was detected by the traditional method of crystal violet dyeing.The growth of the membrane was studied by the method of 12 h,24 h,36 h,48 h,60 h,72 h OD value of the comparison,found that the growth of the biofilm is a rise at first,and began to decrease after reaching the peak,and slowly tend to gentle process.When the growth of bacteria in the 36 h,the adherence of the membrane to the coverslip reached the maximum,with an OD value of about 0.33.The results of this test are also consistent with the results of other experimental studies,which ensures that the correctness of this experiment,and also provides research basis for subsequent SECM experiments.Second,SECM instruments and test probes were debugged and calibrated using SECM as the approximation curve,cyclic voltammetry curve,and X-axis scanning curves.The optimal detection concentration of HQ was determined by square wave voltammetry.When the HQ concentration was 4 mmol/L,the SECM could receive good electrical signal strength while avoiding the high concentration of the test reagent,which could damage the SECM instrument and the Detection of bacterial membrane.These experiments provide a basis for the subsequent investigation of the supernatant morphology and the real-time changes of catalase in the membrane.In this paper,the feasibility of using HQ and H2O2 to detect the catalase in immobilized bacteria membrane was verified by the simulation of catalase.The initial morphological scans of Staphylococcus aureus were carried out using SECM.By adjusting the scanning speed,different morphological images of the vines were provided,and preliminary SECM image analysis was performed.The real-time monitoring of catalase in Staphylococcus aureus was carried out,and the detection peak current obtained from the bacterial membrane of different culture periods was analyzed and analyzed.The results showed that the formation of Staphylococcus aureus Changes in the amount of catalase:The amount of catalase increases with the increase in the amount of membrane formation,and decreases with the dissolution of the membrane. |
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