Research On The Preparation And Application Of Magnetic Polymer Microspheres

Now with the research development in field of biomedicine and bioengineering,People are exploring various functional Polymer microspheres which can serve as smart or intelligent tools for Immunoassay and Immobilization of Enzyme.The purpose of this paper is to construct a rap-id, sensitive and automatic detection of HCG via magnetic enzyme-linked chemiluminescence method.Aim to solve the shortages of the current magnetic polymer microspheres, such as poor monodispersity, weak magnetic responsiveness, ATRP (atom transfer radical polymerization) is introduced into the magnetic polymer microspheres preparation. The microspheres is obtained with the properties of controllable relative molecular mass, narrow-distributed particle size, strong magnetic responsiveness and the surface filled with active functional groups.And then the application performance of the magnetic polymer microspheres is studied in the HCG magnetic enzyme-linked chemiluminescence detection. Particular research contents and results are as follows:1, the magnetic nanoparticles are got by chemical coprecipitation preparation, then the chlorine methyl benzoic acid (initiator) is branched onto the magnetic particles surface. With laser granularity instrument, transmission electron microscopy (SEM) and infrared detector, some properties are confirmed about the magnetic particles branched with chlorine methyl benzoic acid.2, With CuCl-BPY system as a catalytic system, acrylic acid and styrene are added into the reaction system, ATRP is initiated. To find the optimal experimental conditions, the influencing factors of preparation are discussed in detail, such as reaction time, temperature, speed of stirring, etc. Characterization of the surface functional groups is studied through infrared detection, chemical titration methods. It’s found that the surface carboxyl content is up to0.65mmol/g.The microspheres are studied with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that the particles size are about50nm. Hysteresis loop shows that the prepared particles has a very good magnetic responsiveness and super paramagnetism.3, magnetic composite microspheres are used in the detection of HCG. During this study, two different enzyme-linked methods, the relationship between luminous intensity of ALP AMPPD system and the concentration of ALP, optimal testing time and the influence of the concentration of magnetic microspheres for the luminous intensity, are also got detected. The optimum-testing conditions is obtained. Experimental results confirmed that the total testing time is only about2h, the linear range is5-300U/L with the detection limit of2.55U/L and linear correlation index of0.98733.