Microfluidic Chip for Trapping Magnetic Nanoparticles and Heating in Terms of Biological Analysis

In this study, we reported the results of the design and the fabrication a planar coil in copper (square, a = 10 mm, 15mm high, 90 turns), these planar coils were integrated in a microfluidic chip for trapping magnetic nanoparticles and local heating applications. A small thermocouple (type K, 1 mm tip size) was put directly on top of the micro-channel in poly(dimethyl-siloxane) in order to measure the temperature inside the channel during applying current. The design of planar coils was based on optimizing the results of the magnetic calculation. The most suitable value of the magnetic field generated by the coil was calculated by ANSYS® software corresponded to the different distances from the coil surface to the micro-channel bottom (magnetic field strength Hmax = 825 A/m). The magnetic filed and heating relationship was balanced in order to manipulating the trapping magnetic nanoparticles and heating process. This design of the microfluidic chip can be used to develop a complex microfluidic chip using magnetic nanoparticles.

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Fabrication of sandwich-like microfluidic chip with circular cross-section micro-channels

International Journal of Modern Physics B ◽

10.1142/s0217979218502880 ◽

2018 ◽

Vol 32 (26) ◽

pp. 1850288 ◽

Cited By ~ 1

Author(s):

Hong Cheng Wang ◽

Miao Miao Zhao ◽

Li Qun Wu

Keyword(s):

Cross Section ◽

Microfluidic Chip ◽

Low Cost ◽

Circular Cross Section ◽

Middle Layer ◽

Channel Cross Section ◽

Heating Process ◽

Micro Channel ◽

Micro Channels ◽

Glass Capillaries

In microfluidic chips, most micro-channel cross-section shapes are rectangular or triangular in existing chip fabricating technologies, including hot embossing, lithography, etching, injection molding, etc. However, compared with the above micro-channel shapes, a circular shape has advantages in aspects of fluid flow, droplet generation, heat transfer and blood vessel replication. This paper presents a sandwich-like microfluidic chip with circular cross-section micro-channels. The sandwich-like structure includes three layers. The top and bottom layers are PDMS material while the middle layer is composed of micron glass capillaries (used as micro-channels) with circular cross-sections. The glass capillaries are made of borosilicate tube by a glass heating process. Sphere shaped paraffin wax is used as a sacrificial material to form micro-channel junctions. To test the functions of the fabricated micro sandwich-like microfluidic chip, a droplet generating experiment was conducted in the T-junction chip. The droplet size can be controlled in the range of 20–400 [Formula: see text]m by varying the water and oil flow rates. This proposed microfluidic chip structure has the advantages of short processing cycle, low cost and small flow resistance.

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Improved Suzuki–Miyaura reaction conversion efficiency using magnetic nanoparticles and inductive heating

Journal of Materials Science ◽

10.1007/s10853-021-06591-w ◽

2022 ◽

Author(s):

Alejandro Villacampa ◽

Luis Duque ◽

Olga Juanes ◽

Francisco Javier Palomares ◽

Pilar Herrasti ◽

...

Keyword(s):

Magnetic Field ◽

Catalytic Activity ◽

Magnetic Nanoparticles ◽

Size Structure ◽

Local Heating ◽

Inductive Heating ◽

High Catalytic Activity ◽

Coupling Reactions ◽

X Ray ◽

Substrate Conversion

AbstractThe use of magnetic nanoparticles in C–C coupling reactions enables the facile recovery of the catalyst under environmentally friendly conditions. Herein, the synthesis of Pd/Fe@Fe3O4 nanoparticles by the reduction of Pd2+ and oxidation of Fe on the surface of preformed Fe@Fe3O4 is reported. The nanoparticles were characterized using a variety of analytical techniques (transmission electron microscopy, Mössbauer spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction) to determine their size, structure, and chemical composition. The catalytic efficiency of these nanoparticles in classical Suzuki–Miyaura coupling reactions was investigated. The nanoparticles achieved high catalytic activity with the application of local heating by an alternating magnetic field. An investigation was conducted at identical temperatures to compare global heating with the application of an external magnetic field; magnetic heating demonstrated excellent substrate conversion in lesser time and at a lower temperature. The catalyst could also be recycled and reused three times, with ~ 30% decrease in the substrate conversion, which is most likely due to the agglomeration of the Pd nanoparticles or poisoning of the Pd catalyst. This approach, which takes advantage of the catalytic activity and magnetic susceptibility of magnetic nanoparticles, can be applied to several organic transformations to improve their efficiency. Graphical abstract

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The Analysis of Radial Deformation on Annular Local Heating Processed Pipe. Study of fitted pipe's manufacturing method due to annular local heating process (Report 2).

QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY ◽

10.2207/qjjws.13.619 ◽

1995 ◽

Vol 13 (4) ◽

pp. 619-627

Author(s):

Toshiaki Araki ◽

Hisao Hasegawa ◽

Takeshi Yamada ◽

Hiroyuki Matsumura ◽

Kazuhiro Aoyama ◽

...

Keyword(s):

Local Heating ◽

Heating Process ◽

Radial Deformation ◽

Manufacturing Method

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Manipulation of light transmission from stable magnetic microrods formed by the alignment of magnetic nanoparticles

RSC Advances ◽

10.1039/d0ra09511g ◽

2021 ◽

Vol 11 (4) ◽

pp. 2390-2396

Author(s):

Yoon Ji Seo ◽

Hyung Gyu Lee ◽

Jun Seok Yang ◽

Hwanyeop Jeong ◽

Jeonghun Han ◽

...

Keyword(s):

Magnetic Field ◽

Magnetic Nanoparticles ◽

Light Transmission ◽

Smart Window ◽

Light Valve

Magnetic microrods were synthesised from magnetic nanoparticles by alignment using a magnetic field. The transparency difference was maximised and the anisotropic features of the rods were used as a light valve to control the transparency of a smart window.

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Advantages and Disadvantages of Using Magnetic Nanoparticles for the Treatment of Complicated Ocular Disorders

Pharmaceutics ◽

10.3390/pharmaceutics13081157 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1157

Author(s):

Elena K. Schneider-Futschik ◽

Felisa Reyes-Ortega

Keyword(s):

Magnetic Field ◽

Magnetic Nanoparticles ◽

Therapeutic Efficacy ◽

Genetic Diseases ◽

Systemic Exposure ◽

Drug Carriers ◽

Three Dimensions ◽

Target Point ◽

Advantages And Disadvantages ◽

Ocular Disorders

Nanomaterials provide enormous opportunities to overcome the limitations of conventional ocular delivery systems, such as low therapeutic efficacy, side effects due to the systemic exposure, or invasive surgery. Apart from the more common ocular disorders, there are some genetic diseases, such as cystic fibrosis, that develop ocular disorders as secondary effects as long as the disease progresses. These patients are more difficult to be pharmacologically treated using conventional drug routes (topically, systemic), since specific pharmacological formulations can be incompatible, display increased toxicity, or their therapeutic efficacy decreases with the administration of different kind of chemical molecules. Magnetic nanoparticles can be used as potent drug carriers and magnetic hyperthermia agents due to their response to an external magnetic field. Drugs can be concentrated in the target point, limiting the damage to other tissues. The other advantage of these magnetic nanoparticles is that they can act as magnetic resonance imaging agents, allowing the detection of the exact location of the disease. However, there are some drawbacks related to their use in drug delivery, such as the limitation to maintain efficacy in the target organ once the magnetic field is removed from outside. Another disadvantage is the difficulty in maintaining the therapeutic action in three dimensions inside the human body. This review summarizes all the application possibilities related to magnetic nanoparticles in ocular diseases.

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Efficient phenol degradation by laccase immobilized on functional magnetic nanoparticles in fixed bed reactor under high‐gradient magnetic field

Engineering in Life Sciences ◽

10.1002/elsc.202100009 ◽

2021 ◽

Author(s):

Ting‐Ting Xia ◽

Mei Feng ◽

Chun‐Lei Liu ◽

Chun‐Zhao Liu ◽

Chen Guo

Keyword(s):

Magnetic Field ◽

Magnetic Nanoparticles ◽

Phenol Degradation ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

Gradient Magnetic Field ◽

High Gradient

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Magnetoviscosity of a Magnetic Fluid Based on Barium Hexaferrite Nanoplates

Materials ◽

10.3390/ma14081870 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1870

Author(s):

Dmitry Borin ◽

Robert Müller ◽

Stefan Odenbach

Keyword(s):

Magnetic Field ◽

Experimental Study ◽

Magnetic Nanoparticles ◽

External Magnetic Field ◽

Shear Flow ◽

Magnetic Fluid ◽

Barium Hexaferrite ◽

Dipole Interaction ◽

Field Dependent ◽

Fluid Behaviour

This paper presents the results of an experimental study of the influence of an external magnetic field on the shear flow behaviour of a magnetic fluid based on barium hexaferrite nanoplates. With the use of rheometry, the magnetoviscosity and field-dependent yield-stress in the fluid are evaluated. The observed fluid behaviour is compared to that of ferrofluids with magnetic nanoparticles having high dipole interaction. The results obtained supplement the so-far poorly studied topic of the influence of magnetic nanoparticles’ shape on magnetoviscous effects. It is concluded that the parameter determining the observed magnetoviscous effects in the fluid under study is the ratio V2/l3, where V is the volume of the nanoparticle and l is the size of the nanoparticle in the direction corresponding to its orientation in the externally applied magnetic field.

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