Reusable Embedded Microcoils for Magnetic Nano-Beads Trapping in Microfluidics: Magnetic Simulation and Experiments

Abstract

In this study, a microfluidic chip with integrated coil was designed and fabricated for the aim of effectively trapping magnetic nanobeads (Adembeads®, 300 nm) and measuring the chip’s temperature during the working time. In addition, a reversible technique of bonding Polydimethylsiloxane (PDMS) channels was presented. This bonding process used a coating layer of CYTOP®product as a protection, insulation and low-adhesion layer. The reversible packaging technique allows the bottom substrate to be reused, possibly equipped with sensors, and to use a disposable microchannels network. The FE method was employed to calculate the magnetic field and power consumption by the ANSYS® version 12.1 software. Merit factors were defined in order to synthetically represent the ability of the simulated coil to trap beads for a unit power consumption, i.e. a given heat generation. The simulation results propose a new approach to optimize the design criteria in fabricating planar microcoils. The optimal microcoils were fabricated and then used to realize a magnetic immunoassay in a microfluidic chip. The aim was to integrate these microcoils into a lab-on-chip and obtain a fast and highly sensitive biological element detection.

Microfluidic Synthesis, Control, and Sensing of Magnetic Nanoparticles: A Review

“…Researchers have used this technique widely [ 94 , 95 ]. Figure 8 , taken from [ 96 ], shows how the micro-coils attract the magnetic nanoparticles in a microfluidic channel. Researchers have integrated micro-coils in a microfluidic chip for trapping and sensing the barcode-carrying magnetic nanoparticles [ 96 , 97 ].…”

“…Figure 8 , taken from [ 96 ], shows how the micro-coils attract the magnetic nanoparticles in a microfluidic channel. Researchers have integrated micro-coils in a microfluidic chip for trapping and sensing the barcode-carrying magnetic nanoparticles [ 96 , 97 ]. This chip works an enzyme-linked immunosorbent assays (ELISA)-based immunoassay.…”

“…( c ) Beads trapped with coils. Reprinted with permission from O. Lefebvre, et al, 2020 Micromachines 11(3), 257 [ 96 ] under the terms and conditions of the Creative Commons Attribution (CC BY) license , accessed on 28 June 2021. Copyright 2020 MDPI.…”

Screening of spherical moulds manufactured isotropically in plasma etching conditions

“…[1][2][3] Today, mainstream manufacturing predominantly uses silicon as a substrate material. [4][5][6][7][8] Researchers have actively worked on anisotropic etching chemistry, explaining the etching parameters' effect on the profile. [4,[9][10][11] Many dry etching techniques result in anisotropic etching profiles, [12] but some can produce isotropic silicon etching, such as techniques based on chemistries: xenon difluoride (XeF 2 ), [13,14] sulfur hexafluoride (SF 6 ) plasma, [15][16][17][18] and/or wet etching by using an aqueous solution [19,20] such as Hydrofluoric acid-nitric acid-acetic acid HNA composed of hydrogen fluoride (HF*), nitric acid (HNO 3 ), and acetic acid (CH 3 COOH).…”

Assessment of Flow through Microchannels for Inertia-Based Sorting: Steps toward Microfluidic Medical Devices

“…To minimize the effect of the fabrication process, we have used a commercially available microchannel as our flow model. In addition, while many of these applications involve the single use of a disposable chip or cartridge, there may be some instances where multiple uses of the same microchannel are advantageous [ 27 , 28 , 29 , 30 , 31 , 32 ]. In some cases, only one component of the system is replaced after each use and the remaining components must demonstrate consistent performance over multiple uses [ 27 , 31 ].…”