Biochemical Fundamental Of Enzyme Sensor And Quantization Immunity Index

Enzyme sensor converts physical and chemical signals,'which formed in catalytical reaction, into electrical signals, to detect objects under test. As sensitive components, enzyme has been widely studied because of the efficiency and specificity in reaction.By simulating Horseradish Peroxidase catalyzing reaction of H2O2 oxidizing phenol, the biochemical fundamental of enzyme sensor were studied. The result indicated that:1) Stiffness could not be ignored, and when solving stiffness equations, ODE15S was adapted.2) Obtained the dynamic curves of HRP and its intermediate compounds HRP-I and HRP-Ⅱconcentrations vary over time, and assured the lifetime of HRP-I and HRP-Ⅱ.3) The dynamic curves at different substrate concentrations were obtained, and reactive velocities were compared, which showed simulation could greatly reduce the times of experiment and shorten the experiment cycle.In order to reduce the error signal, ponied out isolated considered temperature and pH value was inconsequently in the actual measurement. Under different temperature and pH, simulated accordingly current of the biosensor, which based on Au colloids and poly (thionine) as matrixes, the detecting system of the biosensor was studied. The result indicated that:1) The function expressions of accordingly current changed with temperature and pH varied were gained, the 40-45℃and pH was between 5.3-5.7 which was the best operating conditions. At discrete test points, only analyzed a single factor could not get the optimum working conditions.2) The function, which current response to temperature and pH value, as the foundation to calibrate enzyme sensor, improve the measurement accuracy and expand the detective scope of enzyme sensor.Complex enzyme sensor could detect a number of indicators at the same time. A comprehensive index could be obtained after processed. Immunity was a comprehensive index that expressed by many indicators. The effects of selenium supplementation dietary on the activity of enzymic antioxidant in Caridina denticulata sinensis were studied in the experiment, and based on the dynamic process, the mechanism was also investigated. The selenium supplementation dietary are 0,0.15,0.30,0.45,0.60 and 0.75μg/g. The results showed that suitable concentration of selenium in the diet can enhance the activity of enzymic antioxidant system significantly, and it represented the dose effect obviously. SOD, CAT, and GPX structured a cooperative system. The experiment demonstrated that the activity of SOD, CAT, and GPX in C. d. sinensis can reach the maximum when the concentration of selenium in the diet is 0.44μg/g,0.44μg/g,0.48μg/g.Through the analysis of the current research index, in comprehensive immunity evaluation two defects were pointed out,1) The state of immunity change was not comprehensively reflected; 2) Using different evaluation indexes could not be compared. Given this, the comprehensive index of immunity was indicated, and the calculation method was defined, analytic hierarchy process and principal component analysis were used to calculate the weight of each index. Based on the literature data, expounded the steps of the calculation method, and obtained the immunity comprehensive index. The effect of experiment results on immunity showed by amount, the quantitative index to evaluate the immunity was offered.