Study on method of magnetic nanoparticles detecting by magnetic sensor
After surface modification,magnetic nanoparticles can be combined with nucleic acid,protein,heavy metal ions and other substances.The content of the substance to be measured can be obtained by detecting magnetic response signal of magnetic particles.Based on the theory of electromagnetism and tunnel magnetoresistance effect,a test platform for detecting magnetic signals of different mass magnetic nanoparticles is designed.The magnetic field generator is optimized by using COMSOL Multiphysics finite element analysis software.The improved coil can expand the uniform area of the magnetic field by 1.5 times and increase the value by 2 Gs under the condition of constant DC current.Compared with the simulation results,the maximum error of the experimental results of the new type of three-turn coil is 6.25%.The magnetic field detection device suitable for conventional samples is selected,the optimal measurement direction of various sensors is analyzed,and the relationship curve between magnetic particle mass and output signal is measured.The experimental results show that with the increase of magnetic particle content in suspension,the output signal of tunnel magnetoresistive(TMR)sensor also shows an upward trend,and the two are in linear proportion.
万方数据
维普
