| With the economic development and the standard of living of people enhancement,the numbers and kinds of foodstuff are more and more enrich.How to enhance the quality of foodstuff and medication sanitation is more and more extrusive,There are more or less disadvantage using conventional analytical methods (chromatography,immunity and microorganism measurement),such as high charge,long time,low sensitive and low definition and so on.Aim at upwards questiOtis,this paper chooses surface plasmon resonance(SPR)biosensor to develop my study.This sensor conquers the disadvantages above,and has the characteristic of real time measurement the reaction process,no purification,no label,high sensitive and no background disturb.This work is as follows:1. The basic response character of glycin,ethanol and glucose were dececIed using three simple SPR biosensors.The resull shows that SPR biosensor has nicer recurrence,high sensitive and veracity.2. Mercaptopropionic acid(MPA)was used as the floor,and DNA was combined to gold film to form the sensitive layer,then the SPR biosensor was fabricated.The active condition, such as ion inteasion,pH value,the single/double chain of DNA,recurrence and stability,were optimized.This was used to measure neomycin,and built a system to determine neomycin.The detectable linear range of neomycin concentration was 5.00×10~-9～5×10~-5 mol/L,and the detectable minimum was 1.00×10~-10 mol/L.Meantime,the dynamical characteristic between neomycin and DNA was analyzed,the associated rate k_αis 1.10×10~4 L/mol·s,the dissociated rate K_d is 1.05×10~-3/s,and the binding constants K_D is 1.05×10~7 L/mol.Electrochemical biosensors were also used to determine the same neomycin.The experiment condition,such as pH value, scan rate,and disturbance,were optimized.Compared the two methods above,we can see that the SPR biosensor not only can measure the process of modified sensor and sample ??determination real time and online,but also better than electrochemical biosensors on the detectable linear range and the detectable minimum.But the binding constants K_D of the two methods basically inosculate.Then dependability of the two methods are conformed each other.3．Based on self-modified monomolecular film technology and covalence communion technology,the avidin was liganded on gold surface,and using the strong appetency between avidin and biotin,the biotin antigentamicin was liganded on the gold surface too.Using the special ligand between antibody and antigen,the gentamicin can be liganded on the sensor. Through forming the multilayer film on the sensor surface,the response signal of measured object was magnified.This makes the sensitive of SPR biosensor enhanced strongly,from 1×10~-(13)mol/L to 5×10~-(11)mol/L,and the detect range enlarged from 1×10~-(10)～1×10~-7 mol/L to 5×10~-(13)～1×10~-8 mol/L.These fruits all have not been reported in other papers.At the same time, the dynamical characteristic between antibody and antigen was also been studied,got that the binding ability of the enhanced system is more excelled than direct immunity measurement clearly.The residual and the dynamical characteristic of antibiotic(neomycin,gentamicin)in animality production was analyzed using these sensors,and this settles basic for this method fact apply development from the research phase in laboratory to food machining and medicine sanitation safety domanial.The innovation of this paper is as follows:The DNA-SPR biosensor and avidin-biotin enhanced SPR biosensor which is self prepared can real time and dynamically watch the ligand condition between DNA and neomycin and between gentamicin antibody and antigen.A kind of high sensitive method to detect biologic samples was built,and the dynamical characteristic was discussed,these fruits have not been reported before in other papers.
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