title: Magnetic-particle-sensing based diagnostic protocols and applications.
abstract: Magnetic particle-labeled biomaterial detection has attracted much attention in recent years for a number of reasons; easy manipulation by external magnetic fields, easy functionalization of the surface, and large surface-to-volume ratio, to name but a few. In this review, we report on our recent investigations into the detection of nano-sized magnetic particles. First, the detection by Hall magnetic sensor with lock-in amplifier and alternative magnetic field is summarized. Then, our approach to detect sub-200 nm diameter target magnetic particles via relatively large micoro-sized "columnar particles" by optical microscopy is described. Subsequently, we summarize magnetic particle detection based on optical techniques; one method is based on the scattering of the magnetically-assembled nano-sized magnetic bead chain in rotating magnetic fields and the other one is based on the reflection of magnetic target particles and porous silicon. Finally, we report recent works with reference to more familiar industrial products (such as smartphone-based medical diagnosis systems and magnetic removal of unspecific-binded nano-sized particles, or "magnetic washing").
authors.affiliation: Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan. takamura@eiiris.tut.ac.jp.
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Takamura
authors.affiliation: Research Promotion Center, The University of Electro-Communications, 1-5-1 Chofugaoka Chofu, Tokyo 182-8585, Japan. pjko77@uec.ac.jp.
authors.forename: Pil Ju
authors.initials: PJ
authors.lastname: Ko
authors.affiliation: Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan. jaiyam@eiiris.tut.ac.jp.
authors.forename: Jaiyam
authors.initials: J
authors.lastname: Sharma
authors.affiliation: Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan. yukino@eiiris.tut.ac.jp.
authors.forename: Ryoji
authors.initials: R
authors.lastname: Yukino
authors.affiliation: Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan. ishizawa@eiiris.tut.ac.jp.
authors.forename: Shunji
authors.initials: S
authors.lastname: Ishizawa
authors.affiliation: Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan. pjko77@uec.ac.jp.|Research Promotion Center, The University of Electro-Communications, 1-5-1 Chofugaoka Chofu, Tokyo 182-8585, Japan. pjko77@uec.ac.jp.|Department of Engineering Science, University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan. pjko77@uec.ac.jp.
authors.forename: Adarsh
authors.initials: A
authors.lastname: Sandhu
keywords: magnetic particles; magnetic sensor; medical diagnosis; porous silicon; self-assembly