Computer Assisted Molecular Modeling For Chloramphenicol Artificial Antigen Design And Synthesis

Low molecular contaminant in foods are more and more concerned through the world. It is meanningful to develop the immunoassay in a more efficient, rapid and sensitive way, to assure the human healthe and strengthen the supervision of the contaminants and illegal additives. While chloramphenicol was inhibited in many countries, such European Union, United State and China, the chloramphenicol was required to be detected. While the development of the determination techniques, the minimum of an analyte in sample was lower and lower. ELISA as the major screening methods of Chloramphenicol needed to be upleveled, so does the sensitivity. The antibody was the key element and foundation to improve the ELISA performance. In this study, the chloramphenicol and haptens was analysted through melecular informatic methods under the assisted of computer molecular modeling. Antibody titers were negative logarithm as the dependent variable, the rest of the structure information parameter as the dependent variable, the prediction equation of chloramphenicol hapten activity was established.6 series of haptens was designed and synthesis according of the chloramphenicol synthetic rout and the bioconjugation methods of protein. The artificial antigen was charaterised by UV spectrum, Fluorescence spectrum, CD spectrum and SDS-PAGE gel electrophoresis. The HaptenOl series was synthesied through diazotization method, which has many side reactions, and the immunization was effected.Chloramphenicol (CAP), Chloramphenicol base(CAB), Chloramphenicol succinate(HAP), Thiamphenicol(TAP), Florfenicol(FF), Florfenicol amine(FFA), Azidamfenicol(AA) was taken as sample to design the hapten 01 and hapten 02 serises with the same linking arm. The moiety with different size, structure and electronic property has the effect to the immune effect. The methylsulfonyl and notriogen with strong electronic effect can stimulate higher immune response yet the the affinity of the antibodies was not effected. The electronic properties of the moiety has great effect on the recongition of the antibodies. Analytes has the opposite electronic could lead to poor recongition with the componenet antiboies. Hapten03,Hapten04 and Hapten05series was designed to compared the effects of different length, struture and position on the immunization. The results showed that, linking arm with length less than 6 carbon moleculars has little effect on the immune results and the affinity. The linking arm with the benzene ring could elicite stronger immune resul, while the antibody affanity could be the results of the hydrophobic constant and the similarity.In this study, descriptors was decreased through correlation analysis, the descriptors relevented to each other was analysed and one was chosed. The stepwise regression was applied to reduced the varies and the hydrophobic constant LogP and molar refractivity was used to establish the multiple linear regression equation. PIC50=-1.203-0.147 LogP-0.179 Refractivity-0.627 AtomPairTanimoto. The equation was cross validation by leave one method, the correlation between PIC50 predicted value and experimental value was analysis through linear correlation and the R2=0.5147。...