A Magnetic Method to Concentrate and Trap Biological Targets

Li, F.; Kosel, Jürgen

doi:10.1109/tmag.2012.2202644

Cited by 24 publications

(17 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…F m , calculated for an SPB with a radius of 1.4 lm and a susceptibility of 1.2 46 in a solution with a viscosity of 1 Â 10 À3 PaÁs, has a maximum value of 2.2 pN at the edges of the disk, which is sufficient to trap SPBs. 8,9,13,15,[20][21][22][26][27][28][29][30][31][32][33][34][35]47 Fig . 2(c) shows the velocity of an SPB during the trapping process.…”

Section: -4mentioning

confidence: 99%

“…Therefore, in this research, the emphasis is on the capacity of the MMC to isolate and perform selective treatments on cells tagged with SPBs on a simple and integrated platform. The approach we have taken in this paper differs from our previous work [26][27][28][29][30][31][32][33][34] and from other work in terms of simplicity of fabrication, operation of the device as well as using living cells and also by the integration of all components into a microfluidic chip. Moreover, compared to the commercially available products, the MMC is an integrated chip of small size (3.1 Â 2.3 cm 2 chip area) that enables both cell separation and experiments on-chip.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Isolation of cells for selective treatment and analysis using a magnetic microfluidic chip

et al. 2014

View full text Add to dashboard Cite

This study describes the development and testing of a magnetic microfluidic chip (MMC) for trapping and isolating cells tagged with superparamagnetic beads (SPBs) in a microfluidic environment for selective treatment and analysis. The trapping and isolation are done in two separate steps; first, the trapping of the tagged cells in a main channel is achieved by soft ferromagnetic disks and second, the transportation of the cells into side chambers for isolation is executed by tapered conductive paths made of Gold (Au). Numerical simulations were performed to analyze the magnetic flux and force distributions of the disks and conducting paths, for trapping and transporting SPBs. The MMC was fabricated using standard microfabrication processes. Experiments were performed with E. coli (K12 strand) tagged with 2.8 μm SPBs. The results showed that E. coli can be separated from a sample solution by trapping them at the disk sites, and then isolated into chambers by transporting them along the tapered conducting paths. Once the E. coli was trapped inside the side chambers, two selective treatments were performed. In one chamber, a solution with minimal nutrition content was added and, in another chamber, a solution with essential nutrition was added. The results showed that the growth of bacteria cultured in the second chamber containing nutrient was significantly higher, demonstrating that the E. coli was not affected by the magnetically driven transportation and the feasibility of performing different treatments on selectively isolated cells on a single microfluidic platform.

show abstract

Section: -4mentioning

confidence: 99%

mentioning

confidence: 99%

Isolation of cells for selective treatment and analysis using a magnetic microfluidic chip

et al. 2014

View full text Add to dashboard Cite

show abstract

“…[8][9][10] Magnetic nanoparticles (MNPs) can be remotely manipulated by magnetic fields. Using direct current fields, MNPs can be trapped, concentrated, [11][12][13][14] or used in cell separation. [15][16][17] Under alternating fields, MNPs can be heated 18 or rotated, 19,20 and, in cases of elongated structures, they can transmit forces or torques to whatever they are in contact with.…”

Section: Introductionmentioning

confidence: 99%

Non-chemotoxic induction of cancer cell death using magnetic nanowires

Contreras¹,

Sougrat²,

Zaher³

et al. 2015

IJN

101

View full text Add to dashboard Cite

In this paper, we show that magnetic nanowires with weak magnetic fields and low frequencies can induce cell death via a mechanism that does not involve heat production. We incubated colon cancer cells with two concentrations (2.4 and 12 μg/mL) of nickel nanowires that were 35 nm in diameter and exposed the cells and nanowires to an alternating magnetic field (0.5 mT and 1 Hz or 1 kHz) for 10 or 30 minutes. This low-power field exerted a force on the magnetic nanowires, causing a mechanical disturbance to the cells. Transmission electron microscopy images showed that the nanostructures were internalized into the cells within 1 hour of incubation. Cell viability studies showed that the magnetic field and the nanowires separately had minor deleterious effects on the cells; however, when combined, the magnetic field and nanowires caused the cell viability values to drop by up to 39%, depending on the strength of the magnetic field and the concentration of the nanowires. Cell membrane leakage experiments indicated membrane leakage of 20%, suggesting that cell death mechanisms induced by the nanowires and magnetic field involve some cell membrane rupture. Results suggest that magnetic nanowires can kill cancer cells. The proposed process requires simple and low-cost equipment with exposure to only very weak magnetic fields for short time periods.

show abstract

“…The same groups introduced recently another novel biosensing method [34,81], which again does not rely on functionalization of the sensor surface. Current carrying microstructures in combination with mechanical microtraps are used to immobilize MNPs.…”

Section: Microfluidic Biosensing Systems: State Of the Artmentioning

confidence: 99%

Microfluidic Biosensing Systems Using Magnetic Nanoparticles

Giouroudi

Keplinger

2013

IJMS

View full text Add to dashboard Cite

In recent years, there has been rapidly growing interest in developing hand held, sensitive and cost-effective on-chip biosensing systems that directly translate the presence of certain bioanalytes (e.g., biomolecules, cells and viruses) into an electronic signal. The impressive and rapid progress in micro- and nanotechnology as well as in biotechnology enables the integration of a variety of analytical functions in a single chip. All necessary sample handling and analysis steps are then performed within the chip. Microfluidic systems for biomedical analysis usually consist of a set of units, which guarantees the manipulation, detection and recognition of bioanalytes in a reliable and flexible manner. Additionally, the use of magnetic fields for performing the aforementioned tasks has been steadily gaining interest. This is because magnetic fields can be well tuned and applied either externally or from a directly integrated solution in the biosensing system. In combination with these applied magnetic fields, magnetic nanoparticles are utilized. Some of the merits of magnetic nanoparticles are the possibility of manipulating them inside microfluidic channels by utilizing high gradient magnetic fields, their detection by integrated magnetic microsensors, and their flexibility due to functionalization by means of surface modification and specific binding. Their multi-functionality is what makes them ideal candidates as the active component in miniaturized on-chip biosensing systems. In this review, focus will be given to the type of biosening systems that use microfluidics in combination with magnetoresistive sensors and detect the presence of bioanalyte tagged with magnetic nanoparticles.

show abstract

A Magnetic Method to Concentrate and Trap Biological Targets

Cited by 24 publications

References 3 publications

Isolation of cells for selective treatment and analysis using a magnetic microfluidic chip

Isolation of cells for selective treatment and analysis using a magnetic microfluidic chip

Non-chemotoxic induction of cancer cell death using magnetic nanowires

Microfluidic Biosensing Systems Using Magnetic Nanoparticles

Contact Info

Product

Resources

About