Preparation And Electrochemical Performance Of Molecularly Imprinted Polymer

At present, nanoscale composite organic-inorganic material is a research hotspot in the field of materials. And in the field of the research of preparation of molecularly imprinted electrochemical sensor, the preparation of inorganic composite sols by sol gel technology and the study on molecularly imprinted polymer electrochemical sensors were increasing attented by the researchers, because the inorganic nano-materials has high surface area, as well as high bio-compatibility and relatively good conductivity of the metal inorganic materials. In this paper, on the basis of a large number of literature research, the synthesis of molecularly imprinted polymers were reviewed and new materials used in the latest progress in the field of molecular imprinting. Furthermore, on this basis, oligomeric methyl silsesquioxane (O-MSSQ)-TiO2composite sols and silicon dioxide/tin antimony oxide composite sols were designed and synthesized, as well applied to prepare molecularly imprinted sensors. And the dynamic behavior of filming of O-MSSQ-TiO2composite materials was studied detailedly by in situ FTIR technology. In addition, the electrochemical detection performance of two kinds of molecularly imprinted sensors was researched with the electrochemical method. The main results were as follows:Under the condition of a certain temperature, O-MSSQ-TiO2composite sols were crosslinking and curing to become the network polymer through the condensation of Ti atom and Si atom to form the Si-O-Si, Si-O-Ti and Ti-O-Ti step by step with the acetylacetone groups which were residual on the surface of TiO2disintegrating. The degree of curing of the composite sols was higher with rising of cure temperature and the extension of time. Furthermore, the composite crosslinking films have good thermal stability. Once removing procainamide hydrochloride in MIP film, the surface roughness of the MIP film had became larger obviously, the surface area of MIP film increased and specific binding sites for procainamide hydrochloride has been prepared on the film. Then, a linear relationship between the anodic peak current and procainamide hydrochloride concentration over a concentration range from3.9984×10-9M to4.9751×10-5M was obtained through the detection by the molecularly imprinted sensor. And linear regression equation was:ipa/μA=0.03763c/μM+0.12436, with a correlation coefficient (r) of0.994. Then, the detection limit was estimated to be1.3328×10-9M. Then, it was found that2000-fold concentrations of D-(+)-glucose,50-fold concentrations of ascorbic acid,40-fold concentrations of dopamine hydrochloride,50-fold concentrations of (-)-norepinephrine,40-fold concentrations of adrenaline, did not interfere with the procainamide hydrochloride detections. The recoveries of procainamide hydrochloride were investigated by standard addition method in the human blood serum sample and the recoveries of the sensors varied from96.77%to101.35%.The conductivity of the composite sol was improved by adding tin antimony sol ATO. Then, a linear relationship between the anodic peak current and (-)-norepinephrine concentration over a concentration range from9.99×10-8M to1.4978×10-5M was obtained through the detection by the SiO2-ATO molecularly imprinted sensor. And linear regression equation was:ipa/μA=0.32047c/μM+0.92342, with a correlation coefficient (r) of0.99118. Then, the detection limit was estimated to be3.33×10-8M. Then, it was found that20-fold concentrations of D-(+)-glucose,50-fold concentrations of ascorbic acid,10-fold concentrations of dopamine hydrochloride,15-fold concentrations of adrenaline, did not interfere with the (-)-norepinephrine detections. The recoveries of (-)-norepinephrine were investigated by standard addition method in the human blood serum sample and the recoveries of the sensors varied from99.67%to104.17%.