Speaker :  Professor Dr. Hitoshi Watarai                       
           Department of Chemistry, Osaka University Japan

Time : PM 15 : 30 , 31 May, Monday

Location :  2nd Floor Seminar Hall Lu Jiaxi Building 

Abstract:

Development of new types of magnets has stimulated novel applications of magnetic fields in analytical chemistry in separation, detection and imaging. Especially, the magnetic analysis of microparticles is important subject under the requirements for the analysis of biological, environmental or functional microparticles. Here, I would like to introduce recent development of new area of magneto-analytical chemistry, which is using various kinds of magnetic fields.
1.      Magnetic force mass analysis in atmospheric condition
     We developed a new principle of MS, which does not need ionization but only uses a magnetophoretic velocity modulation of falling particles in an atmospheric condition. It gives a magnetic susceptibility as well as the mass of a single microparticle.
2.      Dynamic force analysis of chemical bonding by magnetic and electromagnetic forces
      Magnetic or electromagnetic force was used to pull a microparticle bound to a capillary or glass wall by a linker molecule. The dissociation or conformational change of the linker molecule was measured by optical microscope or Raman microscope, and the bond dissociation dynamics and the induced conformational change were evaluated.
3.  Interfacial magnetic susceptibility measurement by magnetophoretic velocimetry
      The migration velocity measurement of microdroplets in a liquid medium with different magnetic susceptibility has been developed as a magnetophoretic velocimetry. The velocity analysis afforded the magnetic susceptibility of the liquid-liquid interface of the droplet. From the interfacial magnetic susceptibility, the interfacial concentration of a paramagnetic ion was absolutely determined.
    Furthermore, the analytical application of Faraday imaging will also be introduced.