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Magnetic-particle-sensing based diagnostic protocols and applications.

Takamura T, Ko PJ, Sharma J, Yukino R, Ishizawa S, Sandhu A - Sensors (Basel) (2015)

Bottom Line: 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.

View Article: PubMed Central - PubMed

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.

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").

No MeSH data available.


Related in: MedlinePlus

(a) An aqueous solution containing superparamagnetic micrometer size columnar beads was dropped into one of reservoirs; (b) An electric field was applied across the channels to manipulate the columnar beads; (c) The external magnetic field was applied to the microfluidic chip to detect the 130-nm-diameter target beads immobilized on the surface of channels. Adapted from [11].
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sensors-15-12983-f012: (a) An aqueous solution containing superparamagnetic micrometer size columnar beads was dropped into one of reservoirs; (b) An electric field was applied across the channels to manipulate the columnar beads; (c) The external magnetic field was applied to the microfluidic chip to detect the 130-nm-diameter target beads immobilized on the surface of channels. Adapted from [11].

Mentions: Figure 12 is a schematic image showing how to detect nano-sized magnetic target particles in PDMS micro-channel. The unique feature of our system is that it utilizes electrostatic manipulation of columnar particles instead of an external pump. Typically, pressure-driven micro fluidic systems are often large and lack portability, which is not suitable for point-of-care testing. In our system, columnar particles, on which the carboxyl group are functionalized and have negative charges in aqueous solution, are manipulated by an electric field induced in the channel by applied voltage between the electrodes created on the edges of the channel as shown in Figure 12a. Followed by the electrostatic manipulation of columnar particles on the sensing area where target nano-sized particles were immobilized as shown in Figure 12b, magnetic self-assembly of columnar particles was induced by an external magnetic field from an electro magnet coil as shown in Figure 12c.


Magnetic-particle-sensing based diagnostic protocols and applications.

Takamura T, Ko PJ, Sharma J, Yukino R, Ishizawa S, Sandhu A - Sensors (Basel) (2015)

(a) An aqueous solution containing superparamagnetic micrometer size columnar beads was dropped into one of reservoirs; (b) An electric field was applied across the channels to manipulate the columnar beads; (c) The external magnetic field was applied to the microfluidic chip to detect the 130-nm-diameter target beads immobilized on the surface of channels. Adapted from [11].
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4507658&req=5

sensors-15-12983-f012: (a) An aqueous solution containing superparamagnetic micrometer size columnar beads was dropped into one of reservoirs; (b) An electric field was applied across the channels to manipulate the columnar beads; (c) The external magnetic field was applied to the microfluidic chip to detect the 130-nm-diameter target beads immobilized on the surface of channels. Adapted from [11].
Mentions: Figure 12 is a schematic image showing how to detect nano-sized magnetic target particles in PDMS micro-channel. The unique feature of our system is that it utilizes electrostatic manipulation of columnar particles instead of an external pump. Typically, pressure-driven micro fluidic systems are often large and lack portability, which is not suitable for point-of-care testing. In our system, columnar particles, on which the carboxyl group are functionalized and have negative charges in aqueous solution, are manipulated by an electric field induced in the channel by applied voltage between the electrodes created on the edges of the channel as shown in Figure 12a. Followed by the electrostatic manipulation of columnar particles on the sensing area where target nano-sized particles were immobilized as shown in Figure 12b, magnetic self-assembly of columnar particles was induced by an external magnetic field from an electro magnet coil as shown in Figure 12c.

Bottom Line: 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.

View Article: PubMed Central - PubMed

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.

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").

No MeSH data available.


Related in: MedlinePlus