Design Of Magnetic Nanoparticles Immunoassay System

This thesis applies the linear relation between the magnetization of magneticnanoparticles and their concentration, in accordance with the Langevin equation, to researchinto the magnetic nanoparticles application in immunoassay field. Preliminary designing asimple measurement system is aiming to experimentally verify the feasibility of the theory ofmeasuring the concentration. This measurement method has a broad application prospect inmany fields, especially in biomedicine, such as the tumor hyperthermia and the nanoparticletemperature imaging.Based on the Langevin equation, this thesis applies the linear relation between themagnetization of magnetic nanoparticles and their concentration, and the imagingreconstruction model of Bernhard Gleich and Jurgen Weizennecker, to form theconcentration imaging. This thesis elaborates the deduction of the measurement thoery.Because the concentration of magnetic nanoparticles is very sensitive to the temperature, theconcentration varies with the ambient temperature. Theoretical deduction of this point isgiven in chapter two. So in the design of the measurement system, the constant temperaturesystem must be considered.Considering the principles of the measurement and comparingdifferent measurements of week magnetization, this thesis chooses a better measurementmethod. And through the experiment test using the lock-in amplifier of the Agilent Company,the feasibility of the method is simply proved. An immunoassay system based on themagnetic nanoparticles is designed.A signal detection soft system is designed based on the data acquisition card of the NICompany. A constant temperature system is designed using the temperature transmitter andthe platinum resistance transducers of the Siemens. The precision of the controlledtemperature is plus or minus0.1Kelvin.